The centrifugal pump will carry out the actual operation of exhaust and water filling when starting and running, and that can make the machine and equipment run better. So I will explain the water filling and exhaust methods of the machine and equipment to you next. Let's have a look.

Because the centrifugal pump generates vacuum pump after the pressure in the pump is pumped out by the centrifugal impeller, so in addition to the centrifugal pump and the self-priming pump with the centrifugal impeller immersed in water, water must be filled into the pump before each pump start, which is also known as the diversion channel. There are two ways to fill water: one is to fill water into the pump immediately (at this time, the air outlet should be opened to drain the gas in the pump); The second is to extract the steam from the pump, create a certain vacuum value (at this time, close the water outlet stop valve), and introduce water resources.

1. Install gate valves at the inlet and outlet to fill water. In this way, a gate valve is installed at the water inlet, and water can be filled into the pump after connecting the water pipe.

2. Fill with water by hand pump. Some water pumps are equipped with built-in hand pumps, and small and medium-sized hand pumps can also be purchased or made by ourselves. The stop valve must be installed on the inlet pipe. After the gate valve is closed tightly, fill the water press with a small amount of water to develop the diversion channel. After the water output of the hand pump, it indicates that the water pump has been filled with water and can be started.

3. Use vacuum technology to exhaust and fill water. The self-exhaust of centrifugal pump is the same as the negative pressure exhaust of mechanical pump, so the water-ring mechanical pump exhaust is used to fill the water channel.

Therefore, when the centrifugal pump cannot carry out the actual operation of exhaust and water filling normally, it must be repaired immediately to prevent endangering all normal applications of the machinery and equipment, or it will continue to cause a certain level of damage to the machinery and equipment.
How to select a vacuum pump?

The centrifugal pump manufacturer pointed out that in order to better discharge the gas in the moisture absorption pipe and generate a certain vacuum value when the centrifugal pump is working, the exhaust pipe must be used. For small pumps, the pump casing and water inlet must be filled with water before operation. In order to better avoid the jump of water injection, the bottom end of the water inlet is equipped with a unilateral pump bottom valve that opens when the water flows upward and closes when it flows downward; Generally, large centrifugal pumps with water seepage specifications above 300 mm are not equipped with bottom valve of water pump, but only use professional vacuum equipment to vacuum drinking water. There is no doubt that the operation of the feed pump will cause inconvenience, resulting in waste.

Principle: Centrifugal pump works by using impeller rotation and then water to produce centrifugal movement. Before running the pump, make sure that the pump casing and the moisture absorption pipe are filled with water. Then run the motor to make the pump shaft push the impeller and water for high-speed running fitness exercise. The water will produce centrifugal movement and be thrown to the edge of the impeller. The water will be injected into the compressed water pipeline of the pump through the flow passage of the volute pump casing.

Structure: Centrifugal pump works by using impeller rotation and centrifugal movement of water. The manufacturer of centrifugal pump pointed out that the basic structure of centrifugal pump is composed of six parts, namely, impeller, pump housing, pump shaft, rolling bearing, sealing ring and ferrule joint.

Centrifugal pump manufacturer

The centrifugal pump manufacturer said that the structural type of the self-priming centrifugal pump has been improved, and it has got rid of the insufficiency of the general pipeline centrifugal pump. The characteristic of self-priming centrifugal pump is that the pump shell is double volute structure. The detergent port is located on the edge of the pump impeller, and there is a large capacity vapor liquid separation chamber on the liquid outlet. Other structures are similar to single pole single suction centrifugal pumps, including sealing rings, mechanical seals, shafts and rolling bearings. When the self-priming pump is in operation for the first time, the water diversion channel must be introduced into the pump casing, and the introduction amount can exceed the pump centerline in the pump casing. After that, the fully automatic suction pipe can be operated at any time and anywhere without introducing the diversion canal, so the application is more convenient than the pipeline centrifugal pump.

Principle: The principle of self-priming pump is to fill the pump casing with water (or there is water in the pump casing itself) before the pump runs. After running, the impeller runs at a high speed to make the water in the impeller channel flow to the volute. At this time, the channel generates a vacuum pump to open the seepage check valve. The gas in the suction pipe enters the pump and reaches the edge through the impeller channel.

Structure: Self priming centrifugal pump is a kind of centrifugal pump, but it is different from centrifugal pump in that it has "self priming" characteristics. The basic structure of the self-priming pump is composed of a suction chamber, a liquid storage chamber, a scroll chamber, a liquid collecting hole, a vapor liquid separation chamber, etc.
What is the purpose of the vacuum pump used in the high gloss machine for mobile phone panel?

Advantages of magnetic pump:

1. Since the drive shaft of the magnetic pump does not need to penetrate the pump casing, but uses the magnetic field to drive the inner magnetic rotor through the magnetic field and the thin-walled transmission torque of the isolation sleeve, thus fundamentally eliminating the leakage channel of the shaft seal and achieving complete sealing.

2. The magnetic pump has overload protection when transmitting power.

3. The magnetic material and magnetic circuit design of the magnetic pump have high requirements, while the other parts have low technical requirements.

4. The maintenance and overhaul workload of magnetic pump is small.

Disadvantages of magnetic pump:

1. The efficiency of the magnetic pump is lower than that of the ordinary centrifugal pump, and it cannot operate at 30% of the lower rated flow, and it is more forbidden to idle.

2. Due to the poor wear resistance of the isolation sleeve material of the magnetic pump, the magnetic pump is generally used to transport the medium without solid particles and the magnetic particle material is forbidden to enter the pump.

3. The magnetic pump with general structure is allowed to transport the liquid containing solid particles with diameter less than 0.15mm (100 mesh) and mass fraction less than 5% (auxiliary system shall be added when exceeding).

4. The pump and motor are connected by a coupling. The coupling requires a high accuracy for the installation of the center line. Improper alignment will lead to the damage of the bearing at the inlet and the wear of the isolation sleeve against unilateral side leakage.

5. The magnetic drive of the magnetic pump has two modes: synchronous drive and asynchronous drive. The inner and outer magnetic rotors of the synchronous drive are equipped with permanent magnets, so the temperature of the liquid transported must be lower than the allowable temperature of the permanent magnet. A certain margin must be reserved. Although cobalt and samarium permanent magnets can reach 350 degrees Celsius, the actual use temperature generally does not exceed 260 degrees Celsius. High temperature on the other side may cause permanent magnet loss of magnetism. The magnetic pump with special structure can reach 450 degrees Celsius.

6. The magnetic pump has high requirements for the material and manufacturing process of the isolation sleeve. If the material is not selected properly or the manufacturing quality is poor, the isolation sleeve cannot withstand the wear of the inner and outer magnetic rotors, resulting in wear. Once it breaks, the medium conveyed will overflow, causing equipment failure and affecting the normal operation of the device.

7. When the temperature of the medium conveyed by the magnetic pump exceeds the specified value, it is necessary to provide cooling outside. For example, the heat insulation chamber is set, the pump chamber is filled with coolant with a pressure higher than the sealing pressure, and the inner magnetic rotor and bearing are cooled. The isolation sleeve with a interlayer can also be used. The interlayer is filled with coolant, or the pump body is equipped with a cooling jacket and a cooling coil. The single structure is complex and the cost is high.
Let your vacuum equipment work healthily and happily

RY-type molten salt pump is a single-stage, single-suction cantilever submerged pump, which is suitable for conveying molten salt (KNO3 53%, Na2NO240%, NaNO37%) with high temperature (temperature ≤ 600 ℃), for industrial departments such as ionic membrane caustic soda, alumina, etc., and also for conveying liquid with other high-temperature special media. RY-type molten salt pump is a series of molten salt pump products independently developed on the basis of years of production of high-temperature submerged pump and molten salt submerged pump, referring to the structure of similar foreign products. It is a special high-temperature pump for molten salt circulation system or molten salt transportation.

The structure of molten salt pump mainly consists of power system, transmission system and conveying system. The power system mainly includes motor and motor support. It is the power source of molten salt pump. The transmission system includes the main shaft and bearing bracket, which is responsible for completing the power transmission. The high-speed operation of the motor is converted into the operation of the impeller to generate the power to transport high-temperature molten salt. The conveying system is mainly composed of conveying pipes, which is used to complete the transportation of high-temperature molten salt.

Before determining the type selection of molten salt pump, the composition of molten salt used should be analyzed first. Including the type of molten salt, service temperature, melting point, gasification point, etc. On the whole, the material of the pump should be resistant to high temperature and corrosion, and its strength and service life should be considered. The gas released by molten salt decomposition at high temperature is more corrosive. Taking the common binary molten salt as an example, the operating temperature of the trough molten salt power station and the tower molten salt power station are different. The operating temperature of the trough molten salt heat storage system is between 220 ℃ and 400 ℃. According to this temperature, 304 and 316 stainless steel can be selected as the material of the molten salt pump; For tower type molten salt power station, the working temperature of molten salt is between 220 ℃ and 550 ℃, and 316, 347 stainless steel or 718 chromium-nickel alloy steel that is more resistant to high temperature and corrosion is required.

The high-speed flow of molten salt will also cause rapid corrosion of the impeller blades of the molten salt pump. The corrosion damage rate is proportional to the medium flow rate. The higher the flow rate, the faster the corrosion rate. Therefore, the flow rate of molten salt should be properly controlled within the safe range.
Take you to understand the use of vacuum pump filter

The centrifugal pump works by centrifugal movement of water when the impeller rotates. Before starting the pump, the pump casing and suction pipe must be filled with water, and then the motor can be started to drive the pump shaft to drive the impeller and make the water perform high-speed rotation. The pressurized water line into the pump.

1. Check whether the pump vibrates abnormally. If vibration occurs, stop the pump immediately for inspection.

2. Check whether the bearing temperature is normal. Too high temperature will accelerate bearing damage and shorten the service life of the pump.

3. Check whether the lubricating oil level is normal. If the lubricating oil expires, it needs to be replaced frequently.

4. Check whether the lubricating oil temperature is normal

5. Check whether the lubricating oil is qualified

6. Check whether the leakage meets the requirements. For serious leakage, please check whether the mechanical seal is damaged.

7. Check whether the sealing fluid operates normally

8. Check whether the sealing cooling medium is normal

9. Check whether the cooling water system is normal

10. Check whether the grounding of the motor is intact. Please pay attention to whether the grounding bolt is loose and tighten it in time.

11. Check whether the motor vibration is normal

12. Check whether the motor bearing temperature is normal

13. Check whether the motor current is normal. If the current is too high, the centrifugal pump will not work properly.

14. Check whether the pump inlet pressure is normal and stable

15. Check whether the pump outlet pressure and flow are normal and stable
Vacuum Pumps for Food Packaging Machines

The efficiency of centrifugal pump is the product of mechanical efficiency, volumetric efficiency and hydraulic efficiency. The efficiency of single-stage centrifugal pump unit is the product of pump efficiency and motor efficiency. How to reduce energy consumption and improve efficiency of centrifugal pump?

1. Application of frequency conversion energy-saving technology. For centrifugal pumps whose design parameters are greater than the actual working conditions, the centrifugal pump will always operate in the high efficiency zone after installing the variable frequency speed control device.

2. Promote the application of high-efficiency energy-saving permanent magnet motor, dual-power motor and other energy-saving new products on the main centrifugal pump.

3. Selection of centrifugal pump. When selecting a new pump, the pump produced by a large manufacturer should be selected to ensure the high efficiency of the centrifugal pump.

4. Maintenance of centrifugal pump.

(1) Frequently check and adjust the shaft end seal of the centrifugal pump to reduce the volume loss;

(2) After 10000 hours of operation, the centrifugal pump should be overhauled to restore the efficiency of the pump;

(3) Applying bellows sealing technology to centrifugal pump can completely eliminate the leakage of centrifugal pump and improve the volumetric efficiency.

5. Clean the filter cartridge regularly, check the pipe connection, and ensure that the inlet pipe of the centrifugal pump is smooth.

6. In strict accordance with the operating regulations of centrifugal pump, before starting the pump, the disc pump must be started, the inlet valve must be opened, the outlet valve must be closed, the exhaust and exhaust must be conducted, and the inlet pressure of the pump must be checked to see if it meets the requirements. Prevent pump cavitation caused by low supply pressure and insufficient flow.

7. Regularly check the pump efficiency of the centrifugal pump, find out the cause of low pump efficiency in time, and take corresponding measures to solve it.
dry screw vacuum pump of reasons for lack of air volume

YW series non clogging submerged pump, GW tubular non clogging sewage pump and LW (WL) vertical sewage pump are all designed based on QW submersible sewage pump according to user requirements and different operating conditions. Their hydraulic models and QW pumps are welcomed and praised by users for their unique design and reliable quality after they are put on the market.

2、 Scope of application:

YW series non clogging submerged pump is applicable to the discharge of industrial, sewage and conveyor belt granular sewage such as factory sewage, sewage discharge stations in main residential areas, urban sewage treatment plant water distribution system, civil air defense drainage station, water supply equipment of water plants, hospitals, hotels, municipal engineering construction sites, mine auxiliary machinery, rural biogas digesters, farmland irrigation, etc. It can also be used in clean water and weak corrosive media.

3、 Service conditions:

1. When the rated voltage is 380 V and the power frequency is 50 Hz, this series of sewage pump products are applicable.

2. The medium temperature shall not exceed 120 ℃, the density shall be less than 1150 kg/m3, and the PH value shall be within the range of 5:9;

3. The height shall not exceed 1000m;

4. The annual viscosity of the conveying medium shall not exceed 1000 CP. The annual viscosity of the conveying medium shall not exceed 1000 CP.

5. When the product is working, it must be completely submerged, but the diving depth shall not exceed 10m;

6. The material of the product is mainly cast iron, which cannot be used in the medium with strong corrosion or strong corrosion.
Roots vacuum unit for oil return of preventive measures

In order to better discharge the gas in the moisture absorption pipe and generate a certain vacuum value during the operation of the general centrifugal pump, the exhaust pipe must be used. For small pumps, the pump casing and water inlet must be filled with water before starting. In order to better avoid the jump of water injection, the bottom end of the water inlet is equipped with a unilateral pump bottom valve that opens when the water flows upward and closes when it flows downward; Generally, large centrifugal pumps with water seepage specifications above 300 mm are not equipped with bottom valve of water pump, but only use professional vacuum equipment to vacuum drinking water. There is no doubt that the startup of the feed pump will cause inconvenience, resulting in waste.

Principle: The centrifugal pump is operated by the centrifugal movement of water generated by the rotation of the impeller. Before starting the water pump, be sure to fill the pump housing and the moisture absorption pipe with water, and then start the motor to make the pump shaft push the impeller and water for high-speed running fitness exercise. The water produces centrifugal movement and is thrown to the edge of the impeller. The water is injected into the pressurized tap water pipeline of the pump through the gate of the volute pump housing.

Structure: The centrifugal pump operates by the centrifugal movement of water generated by the rotation of the impeller. The main structure of centrifugal pump is composed of 61 parts, namely impeller, pump housing, pump shaft, rolling bearing, sealing ring and ferrule joint.

The structural type of self-priming centrifugal pump has been improved to get rid of the shortcomings of general pipeline centrifugal pump. Self priming centrifugal pump has the advantage that the pump casing is of double volute structure. The detergent port is located on the edge of the pump impeller, and there is a large capacity vapor liquid separation chamber on the liquid outlet. Other structures are similar to single pole single suction centrifugal pumps, including sealing rings, mechanical seals, shafts and rolling bearings. When the self-priming pump is started for the first time during operation, the water diversion channel must be introduced into the pump casing, and the introduction amount can exceed the pump centerline in the pump casing. After that, the fully automatic suction pipe can be started at any time and anywhere, without introducing the diversion canal, so the application is more convenient than the pipeline centrifugal pump.

Principle: The design principle of self-priming pump is to fill the pump casing with water (or the pump casing itself has water) before starting the pump. After startup, the impeller runs at a high speed to make the water in the impeller channel flow to the volute. At this time, the channel generates a vacuum pump to open the seepage check valve. The gas in the suction pipe enters the pump and reaches the edge through the impeller channel.

Structure: Self priming centrifugal pump is a kind of centrifugal pump, but compared with centrifugal pump, its big difference is that it has "self priming" characteristics. The main structure of self-priming pump is composed of suction chamber, liquid storage chamber, scroll chamber, liquid collection hole, vapor liquid separation chamber, etc.
What are the general mechanical installation rules for vacuum pumps?

chemical pumps! You can have a look

Everyone should be familiar with chemical pumps. Chemical pumps, centrifugal pumps, magnetic pumps, axial flow pumps, multistage pumps, etc. The inlet and outlet are all connected by flanges, and the corresponding pipes should also be welded with flanges. Today we will talk about what is the looper flange, what is the flange, how to weld and so on.

1、 What is a looper flange, where is the looper flange used and in what pipe fittings?

Looping flange is a movable flange, which is generally matched on the water supply and drainage fittings (* * * is common on the expansion joint). When the manufacturer leaves the factory, there is a flange at both ends of the expansion joint, which is directly connected with the pipeline and equipment in the project with bolts.

2、 How is the flange connected to the pipe and where is it welded?

There are many flange classifications. Flat flange, butt welding flange (long neck flange) and looper flange are generally used. The flat welding flange is used for medium and low pressure. It is welded on both sides by butt welding. The welding depth is 2-5mm from the flange sealing surface. The butt welding flange can be directly butt welded. The looper flange bolt connection does not need welding.

3、 What does flange type mean?

The flange is a connecting piece used to connect the valve and the pipeline. That is, when the valve is connected with the pipeline, the connection is connected by bolts. Therefore, the two end faces of the valve with N uniformly distributed bolt holes are flange type.

1. Flange: flange is a transliteration of flange, which means something or part with flange. This kind of part can be independent, that is, a flange plate, or a combination type. For example, one end or both ends of the pipe have flanges, and there are several through holes on the flange for installing screws. Some bearing outer rings have flanges. This flange can have holes or no holes, and it is only used for positioning the flange.

2. Flange type: the connection between the valve and the pipeline or machinery and equipment is flange connection, which is generally called flange type.

4、 What is a flange?

Flange is a kind of disc part, which is common in pipeline engineering. Flanges are used in pairs. In pipeline engineering, flanges are mainly used for connection of pipelines. For the pipes to be connected, a flange plate shall be installed for each type. Screw flanges can be used for low pressure pipes, and welding flanges can be used for pipes with a pressure of more than 4 kg. Add sealing points between the two flanges and fasten them with bolts. Flanges with different pressures have different thicknesses and use different bolts. When pumps and valves are connected with pipes, parts of these equipment are also made into corresponding flange shapes, also known as flange connection. All connecting parts that are bolted on the periphery of two planes and closed at the same time are generally called "flanges", such as the connection of ventilation pipes. Such parts can be called "flange parts". However, this connection is only a part of the equipment, such as the connection between the flange and the water pump, so it is not good to call the water pump a "flange part". Smaller, such as valves, can be called "flange parts".
What are the causes of backflow of water ring vacuum pump

1. The inlet and outlet pressure, flow and motor current of the centrifugal pump shall be kept in the normal use standard, and it is prohibited to pump for a long time. The flow and head of the acid and alkali resistant centrifugal pump shall be controlled within the range indicated on the signboard as far as possible to ensure that the acid and alkali resistant centrifugal pump operates at the design point, so as to achieve the effect of energy saving and consumption reduction.

2. During the operation of acid and alkali resistant centrifugal pump, the bearing temperature shall not exceed the working temperature by 50 ℃, and the upper limit shall not exceed 90 ℃.

3. Check the sealing condition of centrifugal pump frequently, and report to the workshop for maintenance in case of leakage.

4. Always check the quality of lubricating oil and oil level indicator in the oil tank, and replace them immediately if they are found to be deteriorated to avoid false liquid level.

5. The filter press pump shall be sealed with cooling circulating water. The cooling circulating water shall be kept smooth. The cooling circulating water shall not be interrupted within one week after the new seal ring is replaced.

6. Check whether the pump base and motor are firm. If they are loose, the centrifugal pump will vibrate. Stop the pump immediately to check the root cause when the pump makes an abnormal noise.



7. The centrifugal pump shall be operated for 300 hours within 3 months to replace the lubricating oil, and the lubricating oil shall be replaced within 3-6 months for the second time. After 6~12 months, it shall be lubricated and replaced.

8. Check the condition of instruments and leads to see if the pipes are leaking or loose, or damaged in other forms. If maintenance is needed, it should be carried out immediately.

9. Whether the mechanical seal is always leaking. If there is a leak, the compression degree of the moving ring should be adjusted in time to ensure that the sealing surface does not leak. Do not press too tightly to reduce the service life of the sealing property. Note: The filter press pump is the most demanding working condition in the process flow, and also the position with the largest consumption of spare parts. When the sealing leakage is not serious, the seal will not be replaced. Generally, the closed circulation reuse system of the leaking liquid should be considered in the design, but it is subject to the scarcity of materials.

10. When the acid and alkali resistant centrifugal pump is used in cold winter, the liquid in the pump body and pipeline shall be completely discharged when it is stopped. Avoid freezing.

11. If the acid and alkali resistant centrifugal pump is not used for a long time, it is necessary to disassemble all the pumps, wipe off the water, coat the rotating parts and joints with grease, and install them properly for maintenance.

12. For pumps that are not used, turn the gear once before each shift to ensure that the pumps are in good use.

13. When the acid and alkali resistant centrifugal pump is to be stopped, first turn off the valve and pressure gauge, and then disconnect the motor power supply.
Why the flow of water ring vacuum unit cannot reach

Dadonghai Pump Wuxi Co., Ltd. is a professional centrifugal pump manufacturer. When selecting centrifugal pumps for customers, our pump manufacturers will provide perfect pre-sales services such as centrifugal pump models, centrifugal pump prices, etc. for customers' reference, and our pump manufacturers can provide customers with customized pump products. This information is about how to prevent the motor of centrifugal pump from being burnt:

The motor may fail during operation, and burning is one of them, which not only affects the normal work, but also increases the cost, causing us a lot of trouble. There are many reasons why the motor is burnt out, which is related to the quality of the machine itself and whether the centrifugal pump is used correctly.

After the power is turned on, carefully observe the working condition of the centrifugal pump. The outlet water should be connected evenly and the centrifugal pump can be used without vibration and noise. In case of sudden shutdown during operation, disconnect the power supply immediately and check the cause. The interval between two starts of the centrifugal pump shall be limited to the return of all water in the centrifugal pump. If it starts too early, the motor will be burnt due to excessive resistance and water hammer in the water pipe. In addition, if the centrifugal pump is installed in the well, it should be noted that the flow of the centrifugal pump should be consistent with the normal water yield of the well, otherwise it will form an empty machine and burn the motor.

In order to ensure the normal operation of centrifugal pumps, Dadonghai Pump Industry reminds everyone to pay attention to the following points before using centrifugal pumps:

1. Check whether the centrifugal pump motor winding is open circuit. The insulation condition can be measured with a 500V megohmmeter. When the insulation resistance is lower than 0.5 megohm, the centrifugal pump cannot be used.

2. Remove the filter screen and check whether the rolling pump shaft is sensitive. If not, adjust it before use.

3. Whether the selection of gate fuse capacity is appropriate, and other wires cannot be used to replace the fuse.

4. Turn on the power and check whether the impeller works normally (the power on time shall not exceed 3-5 seconds, otherwise the motor may be burnt out.
How To Eliminate The Axial Force Of Roots Reciprocating Vacuum Unit

With the aggravation of the environmental protection situation, more and more chemical enterprises are required to use magnetic pumps to transport various corrosive materials. As we all know, magnetic pumps cannot idle. As long as they idle for a few minutes, the friction between the shaft and the shaft sleeve inside them will produce extremely high temperature, quickly wear the graphite bearings and shafts, and even burn the inner rotor.

In recent years, domestic magnetic pump manufacturers claim to be able to do anti idling magnetic pumps. Is it true? Does idling magnetic pump really work? Can it really idle for a long time?

Today, I would like to introduce some details to you. I hope it will be helpful to users.

At present, there are two kinds of idling magnetic pumps produced by some domestic manufacturers. One is that ceramic rolling bearings are used to replace the original sliding bearings. When the magnetic pump is short of liquid, the friction coefficient of the rolling bearings is low and the heat generated is relatively small. Therefore, the magnetic pump can be idling without burning the bearings and rotors. The disadvantages of this structure are: it cannot carry high torque, materials with higher density cannot be transported normally, and ceramic bearing balls are fragile.

The other is the LHC idling fluorine lined magnetic pump developed by Green Ring. This magnetic pump is a complete upgrade of the main shaft and shaft sleeve on the original traditional basis. It is filled with nano carbon powder technology to achieve the function of idling and self-lubricating. Relatively speaking, the latter is more in line with idling requirements in terms of technology and practical theory.
water ring compressor of manufacturer: basic characteristics of water ring compressor

The Harm of Centrifugal Pump Cavitation

The cavitation phenomenon of centrifugal pump is one of the common faults of centrifugal pump. Once cavitation occurs in the pump, its flow and head performance will not only decline, but also show obvious high noise and vibration. In serious cases, it will even interrupt the liquid flow in the pump and cannot work normally. Cavitation will also damage the flow passage components of the pump, and even affect the pipeline system. There are many reasons for cavitation, such as quality problems of centrifugal pump products, improper use of operators, etc. Before leaving the factory, the products will pass the quality inspection of multiple procedures, so the influence of human factors is greater. In the working state, the working environment and operating factors of centrifugal pumps account for the vast majority of the cavitation phenomenon of centrifugal pumps.

Cavitation will affect the normal operation of centrifugal pumps, causing many serious consequences.

The performance of centrifugal pump is reduced due to cavitation

Centrifugal pump transfers energy to the medium through the rotation of the impeller and converts it into the pressure energy of the medium. However, cavitation will seriously interfere with the energy transfer between the impeller and the liquid. When cavitation occurs, a large number of bubbles will be generated in the medium, which will block the impeller flow passage, and vortex will be generated locally, increasing the flow loss, reducing the pump flow, head and efficiency. In serious cases, it will also lead to flow interruption, making the centrifugal pump unable to work normally.

Cavitation will damage the overcurrent components

Among the flow passage components of centrifugal pump, the impeller is the part most affected by cavitation. When cavitation occurs, many small pits will gradually appear on the surface of metal materials, and then the pits will continue to develop and expand into honeycomb and groove shapes. In serious cases, perforation will occur, and even the impeller will break, seriously affecting the service life of the pump.

Noise and vibration of pump caused by cavitation

When cavitation occurs, high-frequency liquid collisions will produce various noises. In serious cases, the pump will emit crackling explosions, and at the same time, it will induce the vibration of the pump unit, which in turn will accelerate the generation and rupture of bubbles. When the frequency of liquid hammer is the same as the natural frequency of the pump unit, strong cavitation resonance will occur, which will rapidly increase the amplitude. At this time, if you want to protect the centrifugal pump from greater damage, you must immediately stop for inspection.
rotary vane vacuum pump unit of mechanical seal inspection of common sense

The pipeline centrifugal pump is a novel pump developed for pipeline pressurization and transportation to solve the problem of low pipeline pressure. It has great advantages over the horizontal centrifugal pump currently used. The advantages of pipeline pump are mainly reflected in the following points:

1. Pipeline pump is applicable to pressurized water delivery for high-rise buildings, garden sprinkler irrigation, cooling tower water supply, long-distance water delivery, air conditioning, refrigeration washing, bathroom and other cooling systems; Warm water is pressurized circularly, and the operating temperature is below 80 ℃.

2. It is applicable to high-temperature hot water pressurization cycle in heating, boiler and other industries. The operating temperature is below 150 ℃.

3. It is applicable to the transportation of corrosive media in the process flow of food, pharmaceutical, liquor making, chemical and other industries, with the operating temperature below 80 ℃.

4. It is applicable to other industrial sites where there are non corrosive liquids, methane or underground fixed equipment of coal mine Class I, factory Class IIA and IIB, temperature groups T1, T2, T3, T4, and explosive mixtures. The operating temperature is below 80 ℃.

5. The pipeline pump is suitable for conveying corrosive industrial liquids such as chemical, pharmaceutical, petroleum, food, national defense, etc. There are other industrial sites with explosive mixtures in groups T1, T2, T3, T4, such as methane or coal mine underground fixed equipment Class I, factory IIA, IIB. The operating temperature is below 150 ℃.
[url=evpvacuum.com/what-is-the-difference-before-and-after-pvd-coating.html]What is the difference before and after PVD coating?[/url]

All newly purchased and installed centrifugal pump products need to be tested in advance after installation. The following centrifugal pump testing methods and precautions should be followed when testing centrifugal pumps

1. Before starting the centrifugal pump, it is forbidden to run the pump with no load and no load. The liquid test shall be carried out according to the operating procedures specified in the operating instructions of the centrifugal pump. For the forced lubrication system, the temperature rise of the bearing oil of the centrifugal pump shall not exceed 28 ℃, and the temperature of the bearing metal shall be less than 93 ℃.

2. For centrifugal pump of oil ring lubrication or splash lubrication system, the temperature of lubricating oil shall not exceed 39 ℃, and the temperature of bearing parts shall be less than 82 ℃.

3. When testing the centrifugal pump, the vibration value of the bearing of the centrifugal pump should also be checked. The vibration standard of the bearing of the centrifugal pump can refer to the vibration standard of the relevant petrochemical rotating machinery.

4. During the test run of centrifugal pump, the operation of centrifugal pump shall be very balanced and noiseless, the coolant and lubricating oil system shall be normal, and the centrifugal pump and auxiliary pipeline shall be free of leakage.

5. During the test run of the centrifugal pump, attention should be paid to whether the current of the motor of the centrifugal pump operates within the specified range. If the current exceeds the specified range, it means that the head under the actual working condition is lower than the pump head. At this time, it is recommended to turn down the outlet valve to control the flow of the centrifugal pump so that its current can be used within the rated current range.

6. Various seals and medium leakage of centrifugal pump shall not exceed the following standard requirements:

(1) Clean water centrifugal pump with mechanical seal: light oil 10 drops/min, heavy oil 5 drops/min

(2) Multi stage centrifugal pump products with packing seal: light oil 20 drops/min, heavy oil 10 drops/min

(3) For the magnetic drive pump to transport toxic, harmful, flammable and explosive media, no visible leakage is allowed.
Vacuum System Evacuation, Heating and Exhaust Technology to Introduction

If conditions permit, it is better to read the manufacturer's maintenance instructions and general assembly drawings first to see what special points need attention.

1、 During disassembly:

1. Before removing the thrust bearing, measure the clearance of the balance disc with a dial indicator and make records;

2. When disassembling the multistage pump, all parts must be marked according to the original assembly sequence to avoid confusion and wrong installation during reassembly;

3. Small parts (such as keys) that are not convenient for marking can be put together with impellers or guide vanes (middle section) at the same level.

4. During disassembly, you can visually feel whether there are abnormal parts, such as loose fit.

2、 Parts maintenance:

1. Visually check whether the surface of each part is normal, and all mating surfaces must be free of bumps, scratches, rust, etc;

2. Use measuring tools to measure whether the tolerance of key mating parts is qualified;

3. Measure whether the clearance of impeller seal ring, housing seal ring, guide vane seal ring, interstage shaft sleeve, etc. is within the tolerance range, and replace them if they are excessively worn;

4. Check whether the bearing is in good condition;

5. All sealing rings and gaskets shall be replaced if they are superior;

3、 Reinstallation:

1. First install the rotor and conduct dynamic balance test again;

2. Reassemble all parts in the reverse order of pump disassembly. During reassembly, pay attention to the clearance value of each seal ring again to ensure that it is correct;

3. Before installing the balance disc, measure the total rotor runout;

4. After installing the balance disc, measure the rotor half run.

5. Compared with the total string quantity and half string quantity required on the general assembly drawing of the manufacturer, they should basically meet the drawing requirements. Generally, the half string quantity is about half of the total string quantity.

6. Tighten all the main bolts evenly and diagonally;

7. Draw a dial indicator on the shaft, and rotate the shaft to mark the balance disc. The tolerance shall be in accordance with the drawing requirements and generally shall not exceed 0.06;

8. When installing the thrust bearing, pay attention to adjusting the clearance of the balance disc, and use the adjusting ring in front of the bearing to adjust the clearance of the balance disc to the drawing requirements.
vacuum pump of aluminum wire motor and copper wire motor difference between of comparison

1、 Type of mud flow pump

Mixed flow pump is a kind of pump between centrifugal pump and axial flow pump. Its lift is suitable

Medium. With large flow and wide application scope, it is a good pump type in plain river network areas and hilly areas.

According to the difference of outlet chamber of gear pump, diaphragm pump has volute type and guide vane type.

The volute type mixed flow pump can be divided into horizontal type and vertical type, among which the horizontal type is more widely used; Guide vane mixing

There are also two types of sulfur pumps: horizontal and vertical. The vertical mixed flow pump is similar to the vertical axial flow pump

Medium and small mixed flow pumps, most of which are of chip expansion volute type, and large mixed flow pumps are of guide vane type.

Like axial flow pump, the pr plate of mixed flow pump is generally fixed, but large guide vane mixed flow pump

The blade pairs of are made into fully adjustable ones. According to the needs of operation, the blade can be adjusted at any time

Installation angle to expand its high efficiency operation range.

2、 Structure of mixed flow pump

Compared with centrifugal pump and axial flow pump, mixed flow pump has low lift and large flow, so the impeller

The shape is quite special. Since the difference between the inlet diameter and the outlet diameter of the impeller is small, the flow passage

The ratio of width to outlet diameter is relatively large, so the relative width of volute is greater than that of centrifugal pump

Large. The blade is in a throw curve form from the inlet to the outlet, and the edge of the blade outlet is inclined, resulting in

Centrifugal force and thrust, the direction of water flowing out of the impeller is neither radial (such as centrifugal force

Pump) is not axial (such as uranium flow pump), but is inclined between them, so mixed flow pump

Also called diagonal flow pump. The shape of the mixed flow system impeller is shown in Figure 5. Low specific speed impeller

It is closed, with front and rear cover plates, similar to the impeller of centrifugal pump; High specific speed. L round is open

Type, similar to axial flow pump.
vacuum pump oil change for precautions

Classification of main sealing forms of chemical pumps

Chemical pumps are widely used in chemical, petroleum, metallurgy, light industry, synthetic fiber, environmental protection, food, medicine and other sectors. Compared with other types of pumps, chemical pumps have the advantages of stable and reliable performance, good sealing performance, beautiful appearance, convenient use and maintenance, etc. It plays a great role in improving product quality, reducing leakage, emission, dripping and leakage, preventing pollution and improving the environment. What are the main sealing forms of chemical pumps?

1. Oil seal:

It is a self tightening lip seal with simple structure, small size, low cost, convenient maintenance and small resistance torque. It can not only prevent medium leakage, but also prevent external dust and other harmful substances from invading. It also has a certain compensation ability for wear, but it is not resistant to high pressure. It is generally used in chemical pumps in low-pressure occasions.

2. Gasket seal:

The gasket is the basic element of the static seal of centrifugal pump, which is widely used. The selection of gaskets is mainly determined by the factors such as the medium conveyed by the chemical pump, temperature, pressure and corrosivity.

3. Thread seal:

Generally, there are two types of chemical pumps, one is screw connection gasket seal, and the other is thread plus filling seal, both of which are used for small diameter thread connection sealing occasions. The sealing element of the gasket seal of the threaded electric diaphragm pump is the gasket, and the thread only provides the compression force.

4. Labyrinth seal:

When the design is reasonable, the processing is excellent, the assembly is complete, and the speed is high, the labyrinth seal effect is good. However, in practical applications, there are many chemical pump leaks, so they are not commonly used in chemical pump seals.

5. Packing seal:

It is to put the packing with compressibility and resilience into the stuffing box, and convert the axial compression force of the gland into the radial sealing force, so as to play a sealing role.

This sealing method is called packing seal, and this packing is called sealing packing. The packing seal is widely used in the design of chemical pumps because of its simple structure, convenient replacement, low price, and wide adaptability to speed, pressure and medium.

6. Power seal:

When the chemical pump is running with, the pressure head generated by the auxiliary impeller balances the high-pressure liquid at the outlet of the main impeller, thus realizing the sealing. The auxiliary impeller does not work during shutdown, so the shutdown sealing device must be equipped at the same time to solve the possible leakage of chemical pump during shutdown.

The auxiliary impeller seal is simple in structure, reliable in sealing and long in service life. The chemical pump can achieve no leakage during operation, so it is often used in the chemical pump to transport media containing impurities.
What are the functions of filter rod in Roots vacuum unit

Sewage pump is used in various fields, such as mechanical or electrical equipment, to provide various power required for equipment operation. The sewage pump has reliable quality, simple structure, stable operation, and does not need shaft seal in the actual operation process. Therefore, they are more and more used in industrial and mechanical fields. What are the advantages of sewage pumps in operation?

First, the structure is simple

The structure of the sewage pump of Shanghai Hongdong Pump Industry is not complicated, and it can easily match with different main parts of the motor. Because of its relatively simple structure and easy operation, it is easy to install and use. By changing different models or their own shapes and structures, it can meet the assembly and use requirements of different equipment. At the same time, because of the simple structure, the pump body has low failure rate and is easy to maintain.

Secondly, good stability

The sewage pump has excellent material selection and can maintain good stable performance in the process of using various parameter configurations, which is also the reason why many air pumps or water pumps choose to use. Due to its good stability, it can perform better in dynamic performance, provide more continuous power resources, and ensure the use demand of the pump body in different fields.

Finally, the sealing is good

It is reported that the sealing performance of the sewage pump during operation is very important, which can extend the service life and operation quality performance of the equipment during use. Due to its good sealing performance, the sewage pump is not easy to leak water or air, and can be used in processing and transportation industries with high requirements. Due to its good sealing performance, it will not leak various toxic gases or substances, so that the sewage pump can bring better quality performance to the equipment during use.

It can be seen that the sewage pump is favored and welcomed by various industries in the market. In fact, it is inseparable from its own quality performance and various unique advantages. With the continuous improvement of pump quality in various fields, the advantages of sewage pump in use are more and more obvious. At the same time, the amount of sewage pump is also getting more and more attention from the industry.
vacuum pump unit of judgment and inspection of internal leakage

When installing the vertical multi-stage centrifugal pump, if it is not debugged well in the early stage, it will affect the working performance in the future. Next, we will share the details and matters needing attention in the installation process of the vertical centrifugal pump.

If there are many elbows used on the water inlet pipeline, some water flow resistance will be added, and the elbow should turn in the straight direction, and it is not allowed to turn in the horizontal direction to avoid air collection. When installing the water inlet pipeline, the horizontal section is horizontal or upward, which will collect air in the water inlet pipe, reduce the vacuum degree of the water pipe and the pump, and reduce the suction head of the pump and the water output.

The correct method is to slightly skew the horizontal section towards the water source, not to be horizontal or upward. The vertical multi-stage centrifugal pump inlet is directly connected with the elbow, which will cause uneven distribution of water when it enters the impeller through the elbow.

When the diameter of the water inlet pipe is larger than the water inlet of the pump, a deflection reducer pipe should be installed. Some deflection reducers should be installed on the top of the plane and some on the bottom of the slope. Otherwise, air will be collected, water output will be reduced or cannot be pumped, and there will be a crash sound.

If the diameter of the inlet pipe and the water inlet of the water pump is equal, a straight pipe should be added between the inlet and the elbow of the vertical multi-stage centrifugal pump. The length of the straight pipe should not be less than two to three times the diameter of the water pipe. If the outlet is above the normal water level of the outlet pool, although the pump head is added, the flow is reduced.
Dry vacuum pump system for Vacuum Degassing of steelmaking

The centrifugal pump manufacturer pointed out that in order to better discharge the gas in the moisture absorption pipe and generate a certain vacuum value when the centrifugal pump is working, the exhaust pipe must be used. For small pumps, the pump casing and water inlet must be filled with water before operation. In order to better avoid the jump of water injection, the bottom end of the water inlet is equipped with a unilateral pump bottom valve that opens when the water flows upward and closes when it flows downward; Generally, large centrifugal pumps with water seepage specifications above 300 mm are not equipped with bottom valve of water pump, but only use professional vacuum equipment to vacuum drinking water. There is no doubt that the operation of the feed pump will cause inconvenience, resulting in waste.

Principle: Centrifugal pump works by using impeller rotation and then water to produce centrifugal movement. Before running the pump, make sure that the pump casing and the moisture absorption pipe are filled with water. Then run the motor to make the pump shaft push the impeller and water for high-speed running fitness exercise. The water will produce centrifugal movement and be thrown to the edge of the impeller. The water will be injected into the compressed water pipeline of the pump through the flow passage of the volute pump casing.

Structure: Centrifugal pump works by using impeller rotation and centrifugal movement of water. The manufacturer of centrifugal pump pointed out that the basic structure of centrifugal pump is composed of six parts, namely, impeller, pump housing, pump shaft, rolling bearing, sealing ring and ferrule joint.

Centrifugal pump manufacturer

The centrifugal pump manufacturer said that the structural type of the self-priming centrifugal pump has been improved, and it has got rid of the insufficiency of the general pipeline centrifugal pump. The characteristic of self-priming centrifugal pump is that the pump shell is double volute structure. The detergent port is located on the edge of the pump impeller, and there is a large capacity vapor liquid separation chamber on the liquid outlet. Other structures are similar to single pole single suction centrifugal pumps, including sealing rings, mechanical seals, shafts and rolling bearings. When the self-priming pump is in operation for the first time, the water diversion channel must be introduced into the pump casing, and the introduction amount can exceed the pump centerline in the pump casing. After that, the fully automatic suction pipe can be operated at any time and anywhere without introducing the diversion canal, so the application is more convenient than the pipeline centrifugal pump.

Principle: The principle of self-priming pump is to fill the pump casing with water (or there is water in the pump casing itself) before the pump runs. After running, the impeller runs at a high speed to make the water in the impeller channel flow to the volute. At this time, the channel generates a vacuum pump to open the seepage check valve. The gas in the suction pipe enters the pump and reaches the edge through the impeller channel.

Structure: Self priming centrifugal pump is a kind of centrifugal pump, but it is different from centrifugal pump in that it has "self priming" characteristics. The basic structure of the self-priming pump is composed of a suction chamber, a liquid storage chamber, a scroll chamber, a liquid collecting hole, a vapor liquid separation chamber, etc.
water ring vacuum pump of energy saving and environmental protection functions

The service life of equipment has always been a topic of great concern. Many friends want to buy a device with a longer service life when they buy it. They are afraid that there will be some problems in the use process and they will have to buy a new one. In this way, the personal cost is greatly increased, which is not worth the loss. So, how can we extend the service life of pipeline pump? Next, let's analyze it together!

First of all, if you want to extend the service life of stainless steel pipe pump, you must choose a good brand. Brand is the guarantee of quality. If the pipeline pump with good quality is selected, its service time must be much longer than those with ordinary quality.

Pay attention to maintenance

As you get older, you need maintenance. Otherwise, you will look older and older. Of course, as the number of uses increases, the machine also needs maintenance. If you don't maintain the machine, its service life will be greatly reduced. How to maintain the machine better? You can go to a special machine maintenance shop to repair the pipe pump. In addition, you should clean the pipe pump regularly to prevent the accumulation of debris or garbage from affecting the operation of the pipe pump.

The operation is carried out according to the standard

Some people do not pay attention to the operation specifications in the process of using the pipeline centrifugal pump, which has brought a lot of damage to the pipeline pump. In fact, in essence, whether it is a pipeline pump or a centrifugal pump, a variety of pumps need to adopt correct operating methods.
Magnetic levitation molecular pump for semiconductor industry

The manufacturer tells you what the centrifugal pump pressure gauge has

Pressure is not a benchmark, but a derived force and area. Pressure gauge, also known as pressure gauge, is an industrial automatic instrument used to measure the pressure of gas or liquid. The pressure gauge of centrifugal pump can display and record the pressure value, and can also be attached with a control device. The pressure measured by the instrument includes: pressure, atmospheric pressure, positive pressure, negative pressure and differential pressure. Most engineering measurements are pressure gauges. The unit of pressure is Pa, and other units are: engineering air pressure, millimeter water column, etc.

The main principle of centrifugal pump pressure gauge measurement is as follows: use gravity and pressure balance, such as liquid column pressure gauge, piston pressure gauge measurement; The elastic pressure balance measurement method such as mechanical pressure gauge is adopted; Use pressure related pressure gauges to measure the pressure of other physical properties of substances, such as electronic pressure gauges.

Common liquid column pressure gauges include U-tube pressure gauge, single tube pressure gauge, inclined tube pressure gauge, etc. In practical application, there are many factors that will affect its accuracy, and some specific problems can be ignored - the main factors are environmental temperature change, gravity acceleration, capillarity, etc., which need to be corrected. In addition, it also affects the scale, reading and installation. Its advantages are convenient, simple, real and cheap. Commonly used in laboratories.

At present, commonly used mechanical pressure gauges include spring tube pressure gauge, diaphragm pressure gauge, bellows pressure gauge, etc. The elastic elements are spring tubes, diaphragms and bellows. Because the displacement caused by the deformation of the elastic element is very small, it is usually used as the angular displacement or electrical and pneumatic signals of the indicator for the convenience of display. It is simple, cheap and easy to use, and is widely used in industrial fields.

Installation and technical requirements for mechanical seal of centrifugal pump: technical requirements for machine, pump and mechanical seal accessories: the bending of shaft shall not exceed 0.05mm; All parts in the assembly meet the drawing requirements. When tightening the gland, after the coupling is aligned, tighten the compression screw to prevent the deflection of the flange face; The shaft vibration during mechanical seal installation shall not be greater than 0.1mm. The axial displacement of axis C shall not be greater than 0.5mm; The manufacturing tolerance of the shaft of the mechanical seal part is h8, and the finish is 1.6; The shaft end where the dynamic ring seal is installed and the gland end where the static ring seal is installed shall be chamfered; The installation of pump mechanical seal requires that the movable ring must be able to move flexibly on the shaft after installation.

The above is what the small editor of the centrifugal pump manufacturer told us about the centrifugal pump pressure gauge. I hope it can help you.
Combined Vacuum Pumping Unit System For Overhead Atmospheric And Vacuum Distillation/Fractionation Process

Overview of corrosion resistant abrasive slurry pump:

Corrosion resistant abrasive slurry pump is a new type of piston pump developed on the basis of absorbing advanced technologies at home and abroad. Such products are powerful and widely used. The main conclusions are as follows:

(1) Engineering grouting reinforcement

Various pressure grouting of reservoirs, hydropower stations, dams, ports and wharfs

Foundation treatment, soft foundation reinforcement and grouting

Tunnel backfill grouting and bolt support, subway and mine construction

(2) Ground source heat pump deep well construction (new technology)

It can be used for mud circulation and mortar backfilling

(3) Transportation of building mortar

Weighbridge transportation, masonry or plastering mortar

(4) Mechanical spraying and plastering

Commercial mortar or equivalent mortar conveying and spraying plastering

Advantages of anti-corrosion and wear-resistant mud pump:

High working pressure, large flow, capable of conveying mortar with high sand content

This type of product adopts a pump with double cylinder structure, which can output uniform flow and overcome the shortcomings of uneven flow of existing piston pumps or piston pumps

The mortar pump is mechanically driven, with simple and compact structure, cheap wearing parts, quick and convenient replacement, simple maintenance and low cost
How to Improve the Ventilation Effect of Roots Vacuum Pump Unit

What are the methods of installing submersible sewage pump? You can do this

At present, submersible pumps and submersible sewage pumps are very popular in sewage discharge, because they are cheap, easy to use, and do not occupy space. There are several installation methods of submersible sewage pump, which can be provided for your reference. Submersible sewage pump is the abbreviation of submersible sewage pump, which is the channel based on submersible pump

At present, submersible pumps and submersible sewage pumps are very popular in sewage discharge, because they are cheap, easy to use, and do not occupy space. There are several installation methods of submersible sewage pump, which can be provided for your reference.

Submersible sewage pump is the abbreviation of submersible sewage pump. On the basis of submersible pump, the channel adopts anti blocking design for primary lifting, intermediate lifting and sludge return. It is mainly used in municipal engineering, building construction, industrial sewage and sewage treatment occasions to discharge sewage, wastewater and rainwater containing solids and long fibers.

Two common installation methods

With simple installation conditions and large flow coverage, submersible sewage pump is one of the commonly used lifting equipment in water treatment projects, especially in small and medium-sized projects. There are two common installation methods of submersible sewage pump: coupling installation and mobile installation.

The coupling installation is to connect the pump and the pipe through the coupler, which is convenient to separate the pump from the outlet pipe. The pump can be lifted by the lifting device during maintenance. Coupling installation is applicable to submersible sewage pumps of various specifications. It is a common installation method for submersible sewage pumps. Couplers are supplied in complete sets by equipment manufacturers.

Mobile installation means that the pump outlet pipeline is directly connected to the water surface through a hose, and the submersible sewage pump is placed at the bottom of the pool by its own weight or suspended on a lifting device through an iron chain. The mobile installation does not require the coupler and the pool bottom to be fixed, so it is easy to move. It can be lifted together with the pipeline during maintenance. At the same time, due to the installation mode, it is difficult to bear large torque, and it is only applicable to small submersible sewage pumps.

Explanation of installation condition diagram
Vacuum Pump Current Fluctuation of Causes and Solutions

MD wear resistant multistage centrifugal pump These configurations are indispensable!

MD wear-resistant multistage centrifugal pump is highly efficient, energy-saving, wear-resistant and reliable, and has a long service life. It is especially suitable for mine drainage. It pumps mine water and other similar liquids with a volume concentration of no more than 1.5% solid particles, and the liquid temperature is no higher than 80 ℃.

The existing multi-stage centrifugal pumps are generally designed with the one-dimensional theory for conveying clean water. Our company pumps coal water containing solid particles for the wear-resistant multi-stage centrifugal pumps used in coal mines. Two phase flow design theory is added to improve the pump suction performance and hydraulic design, which improves the pump suction head, reduces the impact wear of coal water in the pump, and can effectively convert energy, thus improving the pump efficiency and prolonging the service life of the pump.

MD wear-resistant multistage centrifugal pump is a sectional horizontal multistage pump. The suction port is horizontal and the discharge port is vertical. The pump is directly driven by the prime mover through the coupling. The pump rotates clockwise when viewed from the prime mover end.

MD type pump is mainly composed of stator, rotor, bearing and shaft seal:

1. The stator is mainly composed of suction section, middle section, discharge section, guide vane, etc. Each section is clamped with tension bolts to form a working chamber.

2. The rotor part is mainly composed of shaft, impeller, balance disc and shaft sleeve. The shaft transmits power to the impeller to make it work. The balance disc is used to balance the axial force. Both ends of the shaft are equipped with replaceable shaft sleeves to protect the shaft.

3. There are two types of bearings: rolling bearing and sliding bearing. One is that rolling bearing is mainly composed of bearing body, bearing and bearing gland, which are lubricated with grease. The other is that sliding bearing is mainly composed of bearing body, bearing cover, bearing pad, dust-proof disc, oil level gauge, oil slinger, etc., which are lubricated with thin oil.

4. The shaft seal adopts the packing seal, which is mainly composed of the seal box, packing and water retaining ring on the water inlet section and the packing box. The liquid in the sealing chamber plays the role of water seal, water cooling and water lubrication, and the water seal water comes from the pressure water in the pump.

Performance parameters of MD wear resistant multistage centrifugal pump:

The motor drives the impeller to rotate through the pin coupling direct pump. The blades in the impeller force the liquid to rotate, work on the liquid, and increase its energy. Under the centrifugal force, the liquid is thrown out around the impeller. The speed energy is converted into pressure energy through the guide vane flow channel. The liquid is collected and flows into the next stage impeller through the guide vane. Repeat the above impeller working process. When the liquid in the impeller is thrown out, The pressure in the impeller inlet is lower than that in the inlet pipe. New liquid is sucked into the impeller under the effect of this pressure difference, and the liquid continuously flows out of the pump.
vacuum unit for the reduction of pumping capacity of reasons

New enterprises need to purchase new machinery to meet the needs of normal operation and production and operation of enterprises. The use of micro vacuum pump in the workshop can effectively reduce the dust and bacteria in the workshop, and improve the product quality, especially the soluble chemicals such as silicon dioxide and sodium chloride. The preservation of vacuum environment can prevent the change of chemical properties. How to select a reliable micro vacuum pump?

1. See product parameters

The product specifications of the micro vacuum pump will show various indicators of the product, which has great reference value for product procurement. The micro vacuum pump has a large pressure regulating range, small electromagnetic interference and large power, which can greatly meet the needs of various industries. For example, if the electromagnetic interference is large during the aviation test, the aircraft's running track will change. In order to avoid the interference of magnetic field, the aircraft should choose the micro vacuum pump with small electromagnetic interference.

2. View product warranty service

When purchasing the micro vacuum pump of Shanghai Hongdong Pump, the manufacturer should have a long warranty period and be honest and trustworthy. If a quality problem occurs during the warranty period and it is found that it is really a product problem, it can be replaced immediately when contacting the manufacturer, without shifting the blame. For new product functions, the manufacturer will notify customers and provide relevant services. For regular customers, the manufacturer will have a promotional activity, so they can deliver goods in advance.

3. Look at the price of the product

When selecting, compare the processes and materials of several products. Customers can ask the surrounding enterprises which micro vacuum pump is durable, investigate the market share of each brand of vacuum pump, select products with high purchase rate and acceptable equipment price, and read the operating instructions carefully before use. The service life of the machine will not be shortened due to manual errors.

Faced with the special needs of customers, the manufacturer of micro vacuum pump should provide corresponding customization services. In the customization process, both the realization of customer needs and the safety of the machine should be paid attention to, but also reasonable transformation should be carried out within the scope of safety standards. The household vacuum pump should not choose the machine with excessive current to avoid short circuit caused by excessive current. During vacuum coating, the rubber hose in operation cannot contact the skin, and excessive pressure may block the skin and blood.
Few other people's vacuum pump failures? That's because I know the seven golden rules!

Operating Instructions for Self priming Pump

The self-priming pump manual attached by many manufacturers basically introduces the self-priming pump model performance parameters, self-priming pump characteristics and scope of use, and the self-priming pump installation dimensions, but there is no specific self-priming pump instructions, * which can not meet the standards of self-priming pump manual, so it is necessary to share knowledge about self-priming pump instructions for users for reference, After the self-priming pump unit is installed and adjusted (refer to the installation of self-priming pump for installation knowledge), water can be added for trial operation.

1. Start

(1) Before starting, check whether the self-priming pump has friction and whether it can rotate flexibly. It is prohibited to start the self-priming pump when there is friction.

(2) For the self-priming pump with suspension oil chamber, check the oil level in the suspension oil chamber to see if it is within the specified range.

(3) Open the inlet valve *; Open the water injection valve to inject water into the pump to discharge the gas in the self-priming pump.

(4) Close the outlet valve and pressure gauge cock.

(5) After the above steps are completed, start the motor and open the pressure gauge cock to see whether the pressure gauge pointer is at the correct position.

(6) Open the vacuum gauge cock and slowly open the water outlet valve. At this time, the position of the pressure gauge pointer will change with the opening degree of the water outlet valve. Stop adjusting the size of the outlet valve when the pointer of the pressure gauge points to the required position under the working condition.

Note: Starting the self-priming pump when the water outlet valve is fully opened will cause overload of the motor; If the inlet valve is turned down to control the flow, cavitation will occur in the self-priming pump. Both should be avoided.

2. Run

(1) The oil level of the self-priming pump with suspension oil chamber must be kept at 1/3 and 2/3 of the oil pointer.

(2) The mechanical seal shall not have any leakage. Otherwise, replace the mechanical seal with a new one.

(3) Check whether the flow and lift (inlet and outlet pressure) of the pump are stable and meet the requirements of the working conditions, whether the current value in the ammeter is stable and within the normal range allowed by the motor, whether the self-priming pump unit has abnormal noise, whether the running noise and vibration are excessive, and whether the temperature of the bearing is within the normal range (the temperature rise of the bearing should generally not exceed the ambient temperature by 35 ℃, but the high temperature of zui should not exceed 75 ℃).

3. Shutdown

(1) Before shutdown, slowly close the water outlet valve, close the vacuum gauge cock, cut off the power, and then close the pressure gauge cock.

(2) For the self-priming pump running in series (less used), the last stage pump shall be closed first when stopping. After stopping, the outlet valve shall be closed, and then the * stage pump shall be closed.

(3) When the ambient temperature of the pump installation location is low, the liquid in the pump shall be discharged after shutdown to avoid freezing the pump or pipeline system.

If the liquid level is higher than that of the pump and water can flow into the pump body, we suggest that centrifugal pump be used. If the liquid level is lower than that of the pump, all kinds of self-priming pumps need to be selected
vacuum pump of three filtering forms

Advantages of Horizontal Screw Centrifugal Pump

1. Real non clogging performance: spiral centrifugal pump has extraordinary non clogging performance. The open economic belt of the pump has the characteristics of high efficiency and non clogging, and it is easier to transport solid and long fiber chemicals with large volume. Generally speaking, the non clogging centrifugal pump is usually hooked by the edge of the leaf when the long fiber and solid enter the safe passage, or stay or block in the middle of the import and export trade, leading to equipment failure. Equipped with spiral suction centrifugal impeller, this problem will not be met. The spiral centrifugal impeller will automatically tighten the soft plastic solid, so that the filler cannot be blocked at the inlet, and the inner chamber of the suction port and the back of the centrifugal impeller are also designed with an external thread groove in the opposite direction that can avoid fiber accumulation.

2. Mild material delivery: Another advantage of the spiral design scheme is: "mild delivery", that is, solid chemical substances pass along with the flow without colliding with all positions in the pump. This advantage can be used in the following industries: transportation of specific loose chemicals can maintain their original physical conditions, and loose chemicals are not easy to be torn and crushed. The oil in the moisturizing lotion can maintain its special characteristics. Floating fibers are not easy to be twisted or coiled. Fragile (sensitive) objects, such as tomatoes and fresh fish, are not easy to be destroyed.

3. Excellent operation curve: high efficiency=low operation cost; Steep performance curve=stable operation; Low net suction force=high natural suction capacity; Smooth output power curve=no load area; High speed rotation=delicate structure

4. High solid content material solving ability

5. Selection of adjustable wear-resistant lining: it is an ideal selection under the condition of severe damage. When damage occurs, only one lining can be removed and replaced, and it is not necessary to remove and replace all casings, which is convenient and economic.
How to carry out no-load test run of vacuum unit
Liquid ring vacuum pump

CQB-F fluoroplastic magnetic drive pump adopts magnetic coupling transmission, and there is no dynamic sealing point, so the phenomenon of running, emitting, dripping and leaking at the shaft seal of general shaft drive centrifugal pump is completely eliminated. Its flow passage parts are made of fluoroplastic industrial ceramics, which have excellent corrosion resistance, sealing performance, no aging, no toxin decomposition and other advantages. The drive power below 3kW or less than DN50mm is the magnetic drive pump of perfluorinated plastics.

Characteristics of CQB-F Fluoroplastic Magnetic Pump

The magnetic pump is compact in structure, beautiful in appearance, small in volume, low in noise, reliable in operation, and convenient for use. The casing of the pump body is fixed with metal materials, so the pump body is enough to support the weight of the pipeline, and is convenient for use and maintenance. Flow: 1.8-100m3/h Lift: 8-32m Power: 0.12-22KW Applicable temperature: - 20~100 ℃

Application of CQB-F Fluoroplastic Magnetic Pump

It does not contain solid particle corrosive liquid, strong acid, strong base, ethanol, bleach, photographic solution, nitric acid, hydrochloric acid, hydrofluoric acid, acetic acid, sodium hydroxide, acetone, tetraoxyethane, seawater, brine, etc.

Model meaning of CQB-F fluoroplastic magnetic pump:

CQB50-40-125F

CQB magnetic drive centrifugal pump

50 - Diameter of suction inlet (mm)

40 - Discharge outlet diameter (mm)

125 - Nominal diameter of impeller (mm)
vacuum unit to avoid friction of methods

Application Scope and Theory of Pneumatic Diaphragm Pump

Pneumatic diaphragm pump is a new type of conveying machinery, which is the latest novel pump. Compressed air is used as the power source, and all kinds of corrosive liquids, liquids with particles, high viscosity, volatile, flammable and highly toxic liquids can be pumped out.

Pneumatic diaphragm pump has four materials: plastic, aluminum alloy, cast iron and stainless steel. The diaphragm pump adopts NBR, neoprene, fluororubber, polytetrafluoroethylene and polytetraethylene according to different liquid media. To meet the needs of different users. Anton has achieved satisfactory results in various special occasions when it is used to pump media that cannot be pumped by conventional pumps.

1、 Applicable occasions of pneumatic diaphragm pump

Because the pneumatic diaphragm pump has the above characteristics, the diaphragm pump in the world is gradually invading the market of other pumps since its birth, and has a part of it. For example, diaphragm pumps have occupied an absolute leading position in the paint and ceramic industries, while in other industries, such as environmental protection, wastewater treatment, construction, sewage discharge, and fine chemicals, they are expanding their market share and have an irreplaceable position in other pumps. The upper wind of pneumatic diaphragm pump is:

1. Because it is powered by air, the flow is automatically adjusted with the change of back pressure (outlet resistance), which is suitable for medium and high viscosity fluids. The working point of the centrifugal pump is set based on water. If it is used for the fluid with higher viscosity, it needs to be equipped with a reducer or a frequency converter. The cost has been greatly improved, and the same is true for gear pumps.

2. In flammable and explosive environment, pneumatic pump is reliable and low cost. For example, the transportation of fuel, explosives and gunpowder, because: first, it is impossible to generate sparks after grounding; Second, there is no heat generated during operation, and the machine will not overheat; Third, the fluid will not overheat because the diaphragm pump has the smallest agitation to the fluid.

3. In places where the construction site is bad, such as construction sites, industrial and mining sites

Wastewater discharge, because the impurities in the sewage are many and the composition is complex, the pipeline is easy to be blocked, so the load on the electric pump is too high, and the motor is vulnerable to heat. The pneumatic diaphragm pump can pass the particles and the flow is adjustable. When the pipe is blocked, it will stop automatically until it is smooth.

4. In addition, the diaphragm pump is small and easy to move, does not need a foundation, occupies a very small area, and is simple and economical to install. It can be used as a mobile material delivery pump.

5. In the treatment of hazardous and corrosive materials, the diaphragm pump can completely isolate the materials from the outside world.

6. Or some tests ensure that there is no impurity polluting the raw materials.

7. It can be used to transport fluids with relatively stable chemical properties, such as photosensitive materials, flocculating liquid, etc. This is due to the low shear force of the diaphragm pump, which has little physical impact on the material.

2、 Working principle of pneumatic diaphragm pump

The pneumatic diaphragm pump is a positive displacement pump that changes the volume due to the reciprocating deformation of the diaphragm. Its working principle is similar to that of the plunger pump. Because of the characteristics of the working principle of the diaphragm pump, the diaphragm pump has the following characteristics:

(1) The pump will not overheat: driven by compressed air, the exhaust is a process of expansion and heat absorption. The temperature of the pneumatic pump is reduced when it works, and no harmful gas is discharged.

(2) No electric spark: the pneumatic diaphragm pump is not powered by electricity, and it prevents electrostatic spark after grounding

(3) It can pass the liquid containing particles: since the volumetric operation and the inlet is a ball valve, it is not easy to be blocked.

(4) Extremely low shearing force on materials: how to suck in and how to spit out when working, so the stirring of materials is minimal, which is applicable to the transportation of undisturbed materials

(5) The flow is adjustable. A throttle valve can be installed at the material outlet to adjust the flow.

(6) It has the function of self-priming.

(7) It can run empty without danger.

( It can work by diving.

(9) It can transport a wide range of fluids, from low viscosity to high viscosity, from erosive to viscous.

(10) No complex control system, no cables, fuses, etc.

(11) Small size, light weight, easy to move.

(12) No lubrication is required, so the maintenance is simple, and the working environment will not be polluted due to leakage.

(13) The pump is always efficient and will not be reduced due to wear.

(14) 100% energy utilization. When the outlet is closed, the pump automatically stops, and the equipment moves, wears, overloads, and has a fever
The water ring vacuum pump produces too much waste water and the treatment cost is too high. What is a good solution?