The performance of vacuum pump is affected by the gap between assemblies

 The fit tolerance between assembly parts is a very important parameter, which directly affects the performance of vacuum pump. We have analyzed the precision of the parts and the rough bottom that will appear if the parts are not well matched.

For example, there is a 2x-15 type pump, the user responds that the vacuum degree is always not high, and the pre pumping finds that it operates normally without air leakage, oil leakage, noise and temperature rise, but the vacuum degree is only 20 grids (about 8 * 10-2 Torr). Experience has proved that the vacuum pump oil is too dirty, there is moisture in the oil, the wrong oil is used, the parts in the cavity are worn, and the fitting clearance between parts is too large, etc.
When you start to repair, you can change the oil first, because this method is the most convenient and effective method. Often, the vacuum of some pumps is not high, and the problem can be solved by changing the oil. If you don't change the oil, the next step is to change the oil and clean it. The vacuum degree of the 2x-15 pump is still 20 grids after oil change, so we decided to take it apart for inspection. After cleaning, we measured the cavity size of the parts and found that the end clearance is 4-5 threads, which is partial to the ball. However, considering this kind of clearance, as long as the oil circuit is adjusted properly, it is often possible to install the pengyou after blowing through the oil circuit hole, but it is still 20 grids. When it is disassembled for the second time, check the non perpendicularity (no more than half wire, i.e. Q 005 mm), and find that it is not good, send the surface grinder to grind 2-3 wires off the cavity surface, so that the clearance between the rotary vane and the cavity end cover is less than 2-3 wires, and the non perpendicularity is qualified. In this way, after the assembly, the problem is solved, and the vacuum degree reaches 70 grid ((about 1.5 * 10-2 Torr), which has met the production use.
This example shows that some problems are very complex, sometimes it is difficult to check out without careful inspection. At the same time, we can also see how important the fit clearance of pump parts is.
The above is just a few examples of low vacuum, not including all abnormal reasons such as air leakage. Of course, the vacuum pump oil is insufficient, dirty, oil brand does not match, mixed oil, water in the oil, too thin oil due to friction heat, no proper amount of oil in the pump cavity due to blocked oil circuit, producing sealing oil film, valve plate damage, oil circulation in the pump cavity, poor sealing, etc., which will make the vacuum degree unable to go up. In the valve, exhaust valve: some of the problems listed before, will also make the vacuum can not be improved. The selection of fit clearance and dimensional tolerance of parts are the key points in pump repair, which should be paid more attention to. In addition, some of the diaphragm press in vacuum pump, due to the large amount of interference, make the pump cavity deformation, also produce air leakage, so as to reduce the vacuum degree, improper assembly, end cap screw loose and tight, rotor axis displacement, bad rotor movement or spring deformation, aerator valve gasket damage or not tightened and so on
The vacuum degree of mechanical pump is very low. As long as we find out the corresponding problems and deal with them, we can repair them. However, it should be noted that it must be judged according to the specific situation and careful observation during the test. It is not allowed to act rashly before the situation or cause of disease is clear. In this way, it is easy to damage the parts, increase the scope of failure, and cause adverse consequences or even scrap.

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Pneumatic diaphragm pump is a new type of conveying machinery

Pneumatic diaphragm pump is a new type of conveying machinery, which uses compressed air as the power source. It can pump all kinds of corrosive liquid or liquid with particles, as well as some high viscosity and toxic liquid which is easy to play. The main feature of this kind of pump is pneumatic diaphragm, some of which are stainless steel pneumatic diaphragm. It has many materials, some are plastic, some are stainless steel, and of course some are aluminum alloy. It belongs to the machinery manufacturing industry. There are four kinds of materials for pneumatic diaphragm pump. Do you know what they are? Including cast iron, stainless steel, aluminum alloy and engineering plastics, can be reasonably placed in a variety of occasions for use.
Its application occasions include ceramic industry, and some industries with toxic liquid, environmental wastewater treatment and the use of contemporary construction sewage industry is also very good, the application of fine chemical industry is very strong, it can expand its market share as a whole, and has an irreplaceable position. This kind of pneumatic diaphragm pump is a new type of conveying machinery, which meets the needs of different users. It is installed in a variety of occasions. If it is used for slightly higher viscosity fluid, it needs to be equipped with some reducer or variable frequency speed regulation system, and its cost is increased. However, there is no need for excessive integration of such machinery. In addition, it can be used in some flammable and explosive environments In order to use. In many flammable and explosive environments, its cost is very low. For example, in the transportation process of fuel, gunpowder and explosives, it has a vital influence, because it can not produce sparks after grounding, and there is no heat generated in the work. The machine will not overheat. In some construction sites and construction sites, because there are many impurities in the ascites, and the composition is more complex, the pneumatic diaphragm pump can play its unique role in treating these wastewater.
In addition, the volume of pneumatic diaphragm pump is also very small, easy to move, no foundation is needed, and the floor area is very small. It is very simple, convenient and economical to install. It can use all kinds of materials for decoration. It can completely deal with some hazardous and more materials. This is his advantage and advantage. Moreover, it can be used in the transportation of fluid with unstable chemical properties, such as photosensitive materials, flocculant, etc., because the pressure reduction of the diaphragm pump is relatively low, and the impact on the material is relatively small. We can timely pay attention to the modern characteristics of this kind of pneumatic diaphragm pump on the website. It is widely used in various industries and has made great contributions to our contemporary environmental protection

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Normal performance and lubrication of centrifugal pump

Centrifugal pump in the pump, lubrication standards commonly used and master the knowledge of pump equipment performance is good or bad, the normal operation of the pump is from the analysis of this knowledge, the following description can not be separated;
1. The centrifugal pump runs normally, the work efficiency is good, what teaching content does the development include?
Pressure, steady flow, outlet pressure to meet the needs of normal production, or more than 90% of the nameplate capacity.
Lubrication, cooling control system can be smooth, oil ring, bearing box, liquid level pipe and other complete and easy to use. The selection of lubricating oil meets the national regulations, and the bearing temperature meets the enterprise standard.
Stable operation, no noise, shaft string and vibration meet the standard.
The leakage of shaft seal reaches the standard.
2. What are the functions of the lubricating oil (grease)?
The functions of lubrication system include cooling technology, flushing, sealing structure, vibration reduction, protection and unloading.
3. Does it need to be filtered for three times?
Grade I: between the original barrel and the fixed barrel for lubricating oil;
Second level: fixed between oil barrel and oil pot;
Third floor: between the tank and the filling point.
Lubricant (grease) for pump lubrication in workshop?
Pumps 1350 / 1, 2 use calcium based lubricants. Pump 1146 uses 20 × 10 ~ 3 or 30 × 10 ~ 3 machine oil. The rest of the pumps use 46% machine oil.
5. What is the "12th Five Year Plan" of equipment lubrication?
Fixed point: add oil according to regulations;
Timing: according to the scheduled time of lubricating fuel, and regularly change the oil;
Quantitative: quantitative development and refueling according to consumption;
Qualitative: choose different lubricants according to the model, and keep the oil of acceptable quality;
Fixed person: we must have a special person responsible for every refueling part in China.

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Precautions in operation of corrosion resistant vertical pump

Common faults and treatment of corrosion-resistant vertical pump:
1. The bearing assembly is unreasonable. Reassemble the bearing and shaft, or replace the bearing.
2. The motor shaft and pump shaft are asymmetric or not parallel. Should adjust the motor shaft or pump shaft, if the shaft deformation or bending directly replace the shaft.
3. There is friction in the pump or the impeller is out of balance. The friction should be eliminated or the impeller should be replaced.
4. The pump cavitation is caused by the mismatching of pipe pump characteristics. The pump characteristics should be adjusted to match the pipe characteristics.
5. The local air tightness is eliminated by adding an exhaust valve at the air tightness.
6. If the shaft sleeve is seriously worn, replace it with a new one
7. The elastic pad of the coupling is damaged. Replace it with a new one
Corrosion resistant vertical pump maintenance should pay attention to the following:
1) The water pressure and water quantity of the bearing should meet the requirements, and the tightness of the packing should be adjusted (or replaced) at any time to avoid slurry leakage of the shaft seal. And replace the shaft sleeve in time.
2) When replacing the bearing, make sure that there is no dust in the bearing assembly and the lubricating oil is clean. When the corrosion-resistant vertical pump is running, the bearing temperature is generally 60-650 degrees, and the maximum temperature is not more than 750 degrees.
3) To ensure the coaxiality of the motor and pump, ensure the integrity and correctness of the elastic pad in the coupling, and replace it in time after damage.
4) Ensure that the pump components and piping system are installed correctly, firmly and reliably.
5) Some parts of vertical pump are vulnerable parts. In daily use, we should pay attention to the loss of vulnerable parts and repair or replace them in time. In the process of repairing or replacing the vulnerable parts of corrosion-resistant vertical pump, it is necessary to ensure the correct assembly, reasonable gap adjustment and avoid the occurrence of tight friction.
6) The suction pipeline system of vertical pump must be free of air leakage, and attention should be paid to whether the suction inlet is blocked during operation.

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Gas liquid fraction of stainless steel self-priming pump

Recognition of the volume of gas-liquid separation chamber and outlet height of stainless steel self-priming pump: gas-liquid separation refers to the part outside the pressure chamber of the pump body, and the increasing effect is not obvious. The height from the outlet of the pump body to the center line of the impeller can be determined according to the liquid storage volume. For internal mixing centrifugal self-priming pump, the area of the return hole has a great influence on the self-priming function, so that the liquid returned to the inlet of the impeller through the return hole Many, self-priming, high vacuum height.
Recognition of the clearance between the tongue and impeller in the upper press out chamber: for centrifugal self-priming pump, the clearance between the tongue and impeller has a great influence on the self-priming function. The smaller the clearance between the tongue and impeller in the upper press out chamber, the shorter the self-priming time.
Turning the impeller back cover plate: for the external mixing centrifugal self-priming pump, when the impeller outer circle speed is less than, the self-priming effect is poor. The method of turning the impeller back cover plate is selected to improve the self-priming ability, so as to avoid the circulation of liquid with bubbles at the cut back cover plate and affect the self-priming effect.
Stainless steel self-priming pump can take the initiative to suck up water before the first start-up, and then after the start-up of self-priming pump. It is also very convenient to use. It is widely used in farmland sprinkler irrigation water conservancy projects in China. Before the initiation, there is always a part of water in the pump shell of the self-priming pump. When the impeller of the self-priming pump rolls, the stored water is thrown to the outer edge of the impeller under the effect of centrifugal force, and when the air-water mixture flows to the air-water separation chamber.
As the cross-section increases, the velocity of the air-water mixture decreases, and the air overflows from the exit of the separation chamber. Under the effect of self weight, the water flows back along the lower part of the volute flow passage, and enters the flow passage of the pump shell to mix with the air in the pump again. Then the water flow speed in the inlet pipe is accelerated, and the self-priming effect of the self-priming pump is achieved. The main parts of the self-priming pump are basically the same as the single-stage single suction centrifugal pump.
The method of air supply can not avoid cavitation, but proper air supply can reduce the damage of the channel wall caused by the cavity rupture. The air supply is like a layer of sponge to protect the channel wall. Because the amount of air supply is difficult to grasp, the use of it is very small, so as to achieve good results, the flow, head and power of the pump will decrease a lot, causing adverse consequences.

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What's the difference between an ejector and a vacuum pump?

Ejectors use compressed air to create a vacuum, and vacuum pumps use electricity to create a vacuum.

In terminal applications, the injector is used for low vacuum and low flow applications and the vacuum pump is used for high vacuum and high flow applications. Vacuum pumps can also be used for higher efficiency or clean room applications.

For more information about ejectors and vacuum pumps, visit evpvacuum.com

vacuum unit of continuously improving performance advantages

The improvement of the overall performance of the vacuum unit plays an important role in the development of the enterprise, and it is also the performance of the ability in the growth process of the product. In the face of the development of the whole market of the unit, to improve the level of the overall development ability, it is necessary to expand the practicality of all aspects of the product, promote the effective play of the application ability of the unit, and speed up the production with higher performance advantages Products in the application of the unemployed, improve their ability in all aspects of the demand, with strict technical ability to drive the product as a whole.

Therefore, to enhance the overall quality of the vacuum unit, in order to expand the overall performance of its application ability, we should improve and optimize the production according to the problems in various aspects of the application process, so as to enhance the overall performance of the unit, which is conducive to the practical application ability of the product, so we should face the market competition It is necessary to drive the improvement of the overall level of products, so as to speed up the advantages of all aspects of development and enhance the performance of the overall strength of the enterprise.

Using the advantages of high performance of vacuum unit, it reflects the performance of the actual ability of the product. While promoting the development of its application ability, it also highlights the advantages of the product and improves the competitiveness of all aspects