Pump (Pump) is a machinery that transports fluids or pressurizes fluids, mainly used to transport water, oil, slurry, acid and alkali, emulsion, suspension emulsion, gas mixture and liquid metal, etc., is a common conveying equipment in mining, chemical and metallurgical industries, the following is a list of 19 kinds of pumps (gear pumps, centrifugal pumps, screw pumps, reciprocating pumps, piston pumps, hydraulic piston pumps, mud pumps, pneumatic diaphragm pumps, axial pipeline pumps, self-priming pumps, vortex pumps, water ring vacuum pumps, roots vacuum pumps, rotary vane vacuum pumps, gas booster pumps, Gas-liquid booster pump, steam jet pump) dynamic working principle and characteristics, in order to help you in the selection and use of pumps.
1. Gear Pump:
How it works:
The teeth of the two gears of the gear pump are separated from each other, creating a low pressure, where the liquid is sucked in and sent along the wall of the shell to the other side. On the other side, the two gears close together to create a high pressure to drain the liquid.
Merit:
The structure is simple and compact, small size, light weight, good manufacturability, cheap price, strong self-priming, insensitive to oil pollution, large speed range, impact load, easy maintenance, and reliable work.
Shortcoming:
The radial force is unbalanced, the flow artery is large, the noise is large, the efficiency is low, the interchangeability of the parts is poor, and it is not easy to repair after wear, so it cannot be used as a variable pump.
2. Centrifugal Pump:
How it works:
When the centrifugal pump works, the liquid fills the pump casing, the impeller rotates at high speed, and the liquid produces high speed under the action of centrifugal force.
Performance characteristics:
- High efficiency and energy saving: The pump has an efficient hydraulic shape line and high working efficiency.
- Easy installation and maintenance: Vertical pipeline structure, the inlet and outlet of the pump can be installed in any position and any direction of the pipeline like a valve, and the installation and maintenance are extremely convenient.
- Stable operation, safe and reliable: the motor shaft and the pump shaft are coaxial direct connection, high concentricity, stable operation, safe and reliable.
- Stainless steel bushing: The position of the shaft seal is relatively easy to be corroded, and once the shaft of the direct-coupled pump is corroded, it is easy to cause the failure of the mechanical seal. The stainless steel shaft sleeve is used to avoid corrosion, improve the shaft life, and reduce the operation and maintenance cost.
- Bearing: The middle and lower shaft extension bearings of the motor equipped with the pump are enclosed bearings, which are free of maintenance of the motor bearings during normal use.
- Machine seal: The base parts of the mechanical seal are generally made of rubber bellows structure, and the sealing on the central shaft of the traditional mechanical seal is changed from the line seal of the O-ring to the two-face seal of the rubber parts, which improves the sealing effect when the water medium is clean.
3. Multistage centrifugal pump:
How it works:
Compared with single-stage pumps, the difference between multistage centrifugal pumps and single-stage pumps is that multistage pumps have more than two impellers, which can absorb and pressure water in sections and stages, so as to lift water to a very high position, and the head can increase or decrease the number of stages of the pump impeller according to needs. There are two types of multistage centrifugal pumps, vertical and horizontal, and the pump shaft of the multistage centrifugal pump is equipped with two impellers in series, which can also achieve a higher head than the general single-stage centrifugal pump.
Performance characteristics:
Multistage pumps are mainly used for mine drainage, urban and factory water supply. Compared with reciprocating pumps such as piston pumps and diaphragm pumps, it can also pump a larger flow rate. The multistage centrifugal pump has high efficiency and can meet the needs of high head and high flow conditions, and has been widely used in petrochemical, chemical, electric power, construction, fire protection and other industries. Due to its own particularity, compared with single-stage centrifugal pumps, multistage centrifugal pumps have different and higher technical requirements in terms of design, use and maintenance.
4. Progressive cavity pump:
How it works:
Twin screw pumps are very similar to gear pumps, one screw rotates, the other screw is driven, the liquid is intercepted in the meshing chamber, propelled in the direction of the rod shaft, and then squeezed towards the center for discharge.
Merit:
- Wide range of pressures and flows. The pressure is about 3.4-340 kgf/cm2, and the flow rate can reach 100cm3/min;
- The types and viscosity of the transported liquid are wide, and the concentrator can be used to transport collectors, flocculants, etc.;
- Because the slewing parts in the pump have low inertia forces, very high speeds can be used;
- Good inhalation performance and self-priming ability;
- The flow rate is uniform and continuous, the vibration is small, and the noise is low;
- Compared to other rotary pumps, it is less sensitive to incoming gases and dirt;
- The structure is solid and easy to install and maintain.
Shortcoming:
The machining and assembly requirements of the screw are high, and the performance of the pump is sensitive to changes in the viscosity of the liquid.
5. Reciprocating Pump:
How it works:
When the reciprocating pump works, the piston moves to the right, the pressure in the cavity decreases, the upper valve is pressed down, the lower valve is jacked up, and the liquid is sucked in; the piston moves to the left, the pressure in the cavity increases, the upper valve is jacked up, the lower valve is pressed, and the liquid is discharged.
Merit:
- It can obtain high discharge pressure, and the flow rate is independent of pressure, with good suction performance and high efficiency, of which the steam reciprocating pump can reach 80%~95%;
- In principle, any medium can be conveyed, and it is almost not limited by the physical or chemical properties of the medium;
- The performance of the pump does not vary with pressure and viscosity of the conveying medium.
- Disadvantages of reciprocating pumps: the flow rate is not very stable. It is larger than the centrifugal pump under the same flow rate, the mechanism is complex, the amount of capital is large, and it is not easy to maintain.
Shortcoming:
The traffic is not very stable. It is larger than the centrifugal pump under the same flow rate, the mechanism is complex, the amount of capital is large, and it is not easy to maintain.
6. Double-acting reciprocating pump:
How it works:
When the double-acting reciprocating pump is working, the piston moves to the right, the left down sucks the liquid, and the right upper discharges. The piston moves to the left, the lower right sucks the liquid, and the upper left discharges. The piston reciprocates once, and there are two suction and discharge, and the flow is more uniform.
7. Piston Pump:
How it works:
The piston pump, also known as the electric reciprocating pump, is divided into single cylinder and multi-cylinder from the structure. When the piston pump is working, the reciprocating action of the piston in the cylinder makes the cylinder volume change repeatedly to suck in and discharge the fluid.
Performance characteristics:
- The piston pump is suitable for high pressure and small flow occasions, especially when the flow rate is less than 100m3/h and the discharge pressure is greater than 9.8 MPa, it shows its high efficiency and good operating performance.
- It has good suction performance, can pump a variety of liquids with different media and different viscosity, and can be used for water injection, oil injection and oil recovery in oil fields and coal seams. If the overflow parts are stainless steel, corrosive liquids can be conveyed. In addition, according to the different structural materials, it can also convey high-temperature tar, sludge, high-concentration mortar, high-viscosity liquid, etc.
- Piston pumps are widely used in petrochemical industry, machinery manufacturing industry, papermaking, food processing, pharmaceutical production, etc.
8. Hydraulic Piston Pump:
How it works:
Hydraulic piston pump or solid pump, driven by the hydraulic power pack, the hydraulic cylinder is propelled into the conveying cylinder, and the material in the conveying cylinder is output to the pipeline. Generally divided into single plunger and double plunger, the basic principle of the plunger pump is simple, this pump uses the momentum of a relatively large moving body of water to pump a relatively small volume of water to a high place. Hydraulic piston pumps are widely used in sewage treatment, solid waste treatment, mine metallurgy, dredging, dredging, petrochemical industry, power plants, cement industry and other fields.
9. Mud Pump:
How it works:
The commonly used mud pump is piston type or plunger type, the crankshaft of the pump is driven by the power machine to rotate, and the crankshaft is driven by the crosshead and then the piston or plunger is driven to do reciprocating motion in the pump cylinder. Under the alternating action of suction and discharge valves, the purpose of pressure delivery and circulation flushing liquid is realized. Mud pump refers to the machinery that transports mud or water and other flushing fluids to the borehole during the drilling process, and is an important part of drilling equipment. In the commonly used positive circulation drilling, the surface flushing medium - clean water, mud or polymer flushing liquid is directly sent to the bottom of the drill bit through a high-pressure hose, faucet and the center hole of the drill pipe string under a certain pressure, so as to achieve the purpose of cooling the drill bit, removing the cut cuttings and transporting them to the surface.
10. Air operated diaphragm pump:
How it works:
In order to prevent the live column from being in direct contact with the corrosive material and liquid, the cylinder cavity is separated from the liquid with a diaphragm, which is essentially the principle of the reciprocating pump. The air-operated diaphragm pump is available in four materials: engineering plastic, aluminum alloy, cast iron, and stainless steel.
Performance characteristics:
- Compressed air is used as the power source, which can be used for various corrosive liquids. According to different liquid media, different materials can be used to meet the needs of different users. The pump will not overheat: the compressed air is powered, and it is an expansion and heat-absorbing process when exhausting, and the temperature is reduced when the pneumatic pump is working, and no harmful gases are discharged.
- No electrical sparks: The pneumatic diaphragm pump does not use electricity as power, and prevents electrostatic sparks after grounding
- Can pass through liquids containing particles: because the volumetric operation and the inlet is a ball valve, it is not easy to be blocked.
- The shear force on the material is extremely low: how to suck in and how to spit out when working, so the agitation of the material is minimal, and it is suitable for the transportation of unstable substances
- The flow rate is adjustable, and a throttle valve can be added at the outlet of the material to adjust the flow.
- It has the function of self-priming.
- It can run dry without danger.
- Can dive work.
- A wide range of fluids can be transported, from low viscosity to high viscosity, from corrosive to viscous.
- There are no complex control systems, no cables, fuses, etc.
- Small size, light weight, easy to move.
- No lubrication is required, so maintenance is easy and does not pollute the working environment due to dripping.
- The pump is always efficient and will not be degraded by wear and tear.
- 100% energy utilization, when the outlet is closed, the pump automatically stops, the equipment moves, wears, overloads, heats
- There is no moving seal, easy maintenance and leakage. Work without dead spots.
11. Axial Flow Pipeline Pump:
How it works:
The impeller of the axial flow pipeline pump is designed as an axial flow type, and the speed is very high, and if the motor power, impeller diameter, and pipe diameter are large enough, the flow rate can be large.
Performance characteristics:
- The pipeline pump has a compact structure, integrated machine and pump, small size, and its vertical structure has a small installation footprint, stable operation, and no adjustment is required for installation.
- The pump inlet and outlet are designed with the same flange of the same specification, and are located in the same center online, which can be directly installed on the pipeline like a valve, and the center is low, which is convenient for pipeline layout and installation.
- The pump is coaxial with the motor, and the axial size is short, which makes the pump run more smoothly and has low noise.
- The traditional shaft seal method is canceled, which avoids the leakage of the conveying medium, so it has the remarkable characteristics of no leakage at all.
12. Self-priming pump:
How it works:
The casing is filled with water (or the casing itself contains water) before the pump is started. After starting, the high-speed rotation of the impeller makes the water in the impeller channel flow to the vortex shell, and then the inlet forms a vacuum, so that the water inlet backstop door is opened, and the air in the suction pipe enters the pump, and reaches the outer edge through the impeller channel.
Performance characteristics:
The self-priming pump is a self-priming centrifugal pump, which has the advantages of compact structure, convenient operation, stable operation, easy maintenance, high efficiency, long life, and strong self-priming ability. There is no need to install a foot valve in the pipeline, and only need to ensure that the pump body is stored with quantitative fluid extraction before working. Different liquids can be self-priming pumps made of different materials.
13. Vortex Pump:
How it works:
The liquid in the groove of the blades of the vortex pump is thrown to the flow channel by centrifugal force and pressurized at one time; the liquid in the flow channel is thrown out of the tank to form a low pressure, and enters the groove again and pressurizes again; the vortex movement of the groove is the first groove and one groove is used for many times, so as to obtain a higher pressure head.
Performance characteristics:
- W-type single-stage direct-connected vortex pump is used for sucking clean water or liquid with physical and chemical properties similar to water, using liquid temperature not exceeding 60 °C, often used in boiler feed water, in shipbuilding, textile, chemical industry, metallurgy, machinery manufacturing, aquaculture, fixed fire stabilizer, heat exchanger group, agricultural remote sprinkler irrigation and other departments have a wide range of applications.
- The characteristics of small size and light weight of the vortex pump have great advantages in marine installations. Self-priming is achieved with the ability to self-prime or with the help of a simple device.
- It has a steep head characteristic curve and is therefore insensitive to pressure fluctuations in the system. Some vortex pumps allow for vapor-liquid mixing. This is important for pumping volatile liquids containing gases and high-temperature liquids with high vaporization pressures.
- The structure of the vortex pump is simple, the casting and processing technology are easy to implement, and some vortex pump parts can also use non-metallic materials, such as plastic, nylon molded impeller, etc.
- Disadvantages of vortex pumps: the efficiency is low, up to 55%, and most vortex pumps have an efficiency of 20-40%, which hinders their development in the direction of high power.
- The cavitation performance of vortex pumps is poor.
- Vortex pumps cannot be used to pump viscous media. As the viscosity of the liquid increases, the head and efficiency of the pump decreases dramatically, and the viscosity of the medium is limited to 114 centi.
- The requirements for radial clearance and axial clearance between the vortex pump impeller and the pump body are strict, which brings certain difficulties to the machining and assembly process.
- The medium to be pumped is limited to pure liquids. When the liquid contains solid particles, the axial and radial clearances caused by wear will decrease the performance of the pump or cause the vortex pump to not work.
14. Water Ring Vacuum Pump:
How it works:
The impeller of the water ring vacuum pump vanes is eccentrically mounted in the cylindrical pump housing. A certain amount of water is injected into the pump. As the impeller rotates, the water is thrown to the pump casing to form a water ring, the inner surface of which is tangent to the impeller hub. Because the pump casing and the impeller are not concentric, the air inlet space 4 between the right half hub and the water ring gradually expands, thereby forming a vacuum, and the gas enters the air inlet space in the pump through the air intake pipe. The gas then enters the left half and is discharged to the pump through the exhaust space and exhaust pipe due to the gradual compression of the volume between the hub rings.
Performance characteristics:
- The structure is simple, the manufacturing accuracy is not high, and it is easy to process.
- The structure is compact, the number of revolutions of the pump is high, and it can generally be directly connected with the motor without a deceleration device. Therefore, with a small structural size, a large exhaust volume can be obtained, and the floor space is also small.
- Compressed gases are basically isothermal, i.e., the temperature of the compressed gas process changes very little.
- Since there are no metal friction surfaces in the pump chamber, there is no need to lubricate the pump and there is very little wear. The sealing between the rotating and fastening parts can be done directly by the water seal.
- Uniform suction, stable and reliable work, simple operation and convenient maintenance.
- Disadvantages of water ring vacuum pump: low efficiency, generally about 30%, better up to 50%.
- The vacuum level is low, which is not only limited by the structure, but more importantly by the saturated vapor pressure of the working liquid. With water as the working liquid, the ultimate pressure can only reach 2000~4000Pa. Oil is used as working fluid, up to 130Pa.
- In short, because the gas compression in the water ring pump is isothermal, flammable and explosive gases can be pumped out. Since there is no exhaust valve and friction surface, dusty gases, condensable gases, and gas-water mixtures can be extracted. With these outstanding features, it is still widely used despite its low efficiency.
15. Roots Vacuum Pump:
How it works:
Roots pumps work on a similar principle to roots blowers. Due to the continuous rotation of the rotor, the pumped air is drawn from the air inlet into the space v0 between the rotor and the pump casing, and then discharged through the exhaust port. Since the V0 space is fully enclosed after suction, there is no compression or expansion of the gas in the pump chamber. However, when the top of the rotor turns the edge of the exhaust port, and the V0 space communicates with the exhaust side, due to the high gas pressure on the exhaust side, a part of the gas is flushed back into the space V0, which makes the gas pressure increase suddenly. As the rotor continues to rotate, the gas is vented out of the pump.
Performance characteristics:
- Large pumping velocity over a wide range of pressures;
- Quick start, can work immediately;
- Insensitive to dust and water vapor contained in the pumped gas;
- The rotor does not have to be lubricated, and there is no oil in the pump chamber;
- The vibration is small, the rotor dynamic balance condition is good, and there is no exhaust valve;
- The driving power is small, and the mechanical friction loss is small;
- Compact structure and small footprint;
- Low operation and maintenance costs.
- Therefore, roots pumps are widely used in metallurgy, petrochemical, papermaking, food, and electronics industries.
16. Rotary vane vacuum pump:
How it works:
When the rotor rotates in the direction of the arrow, the volume of the space A that communicates with the suction port is gradually increasing, and it is in the suction process. The volume of space C, which communicates with the exhaust port, is gradually shrinking, and it is in the process of exhausting. The volume of the centered space B is also gradually decreasing and is in the process of compression.
Performance characteristics:
- Since the volume of space A gradually increases (i.e., expands), the gas pressure decreases, and the pressure of the gas outside the inlet of the pump is stronger than the pressure in space A, so the gas is sucked in. When space A is isolated from the suction port, that is, it turns to the position of space B, the gas begins to be compressed, the volume gradually decreases, and finally communicates with the exhaust port. When the compressed gas exceeds the exhaust pressure, the exhaust valve is pushed open by the compressed gas, and the gas is discharged into the atmosphere through the oil layer in the tank. By the continuous operation of the pump, the purpose of continuous pumping is achieved. If the discharged gas passes through the airway and is transferred to another stage (low vacuum stage), it is pumped out by the low vacuum stage, and then compressed by the low vacuum stage and discharged into the atmosphere, that is, a two-stage pump is formed. In this case, the total compression ratio is covered by two stages, thus increasing the ultimate vacuum. Performance characteristics of rotary vane vacuum pump: rotary vane vacuum pump is an oil-sealed mechanical vacuum pump, which belongs to low vacuum pump, which can be used alone or as a pre-pump for other high vacuum pumps or ultra-high vacuum pumps. It is widely used in metallurgy, machinery, military industry, electronics, chemical industry, light industry, petroleum and pharmaceutical production and scientific research departments. Small size, light weight and low noise;
- It is equipped with a gas ballast valve to remove a small amount of water vapor;
- It is equipped with an automatic anti-oil return check valve, which is easy to start;
- The continuous and unobstructed atmospheric operation of the air inlet shall not exceed one minute;
- It is not suitable for pumping gases that corrode metals, have chemical reactions to pump oil, contain particulate dust, and have excessive oxygen content, explosive and toxic gases.
17. Pneumatic Booster Pump:
How it works:
The gas booster pump is powered by compressed air, and the low-pressure gas pressure is continuously output after rising, and the final output pressure can be increased to two times or even dozens of times the pressure of the power source, which is a pollution-free gas booster device. According to the output pressure and structural form, it is divided into low-pressure pump and high-pressure pump.
Performance characteristics:
- The low-pressure pump is mainly used to maintain the normal operation of the pneumatic device and meet the local high-pressure gas requirements of the equipment when the on-site air source pressure is insufficient or unstable, and the minimum operating pressure of the pneumatic device cannot be guaranteed. The high-pressure pump is mainly used for pressurizing non-ordinary compressed air occasions, such as pressurizing nitrogen, helium, argon, etc. to tens of megapascals and loading it into a high-pressure gas storage tank. Performance characteristics of pneumatic booster pump: the working pressure range is large, different pressure areas can be obtained by selecting different types of pumps, and the input air pressure and output air pressure can be adjusted accordingly. It can reach extremely high pressure, gas 90Mpa
- The flow range is wide, and all types of pumps can work smoothly with only 0.1Kg air pressure, so the minimum flow rate can be obtained, and different flow rates can be obtained after adjusting the air intake.
- Easy to control, from simple manual control to fully automatic control.
- Automatic restart, no matter what the pressure of the packing circuit drops, it will automatically restart, replenish the leakage pressure, and keep the circuit pressure constant.
- Safe operation, gas-driven, no arc and sparks, can be used in hazardous situations.
- The maximum energy savings can be up to 70%, as no energy is consumed to maintain the holding pressure.
18. Gas-Liquid Booster Pump:
How it works:
The gas-liquid booster pump is controlled by a high-pressure plunger controlled by a check valve to continuously discharge the liquid, and the outlet pressure of the booster pump is related to the air drive pressure. When the pressure between the drive section and the output liquid section reaches equilibrium, the booster pump stops running and no longer consumes air. When the output pressure drops or the air-driven pressure increases, the booster pump will automatically start running until the pressure equilibrium is reached again.
Performance characteristics:
- A single pneumatic unbalanced gas distribution valve is used to realize the automatic reciprocating motion of the pump, and the air drive part of the pump body is made of aluminum alloy. The wetted part is made of carbon steel or stainless steel according to different media, and the full set of seals of the pump are imported high-quality products, so as to ensure the performance of the gas-hydraulic booster pump. Performance characteristics of gas-liquid booster pump: high output pressure: the maximum output pressure of the liquid pump can reach 640MPa, and the maximum of the air pump can reach 200MPa
- Wide range of use: the working medium can be hydraulic oil, water and most of the chemically corrosive liquids, and the reliability is high, maintenance-free and long.
- Wide range of output flow: For all types of pumps, only a small drive air pressure is needed to work smoothly, and a small flow rate can be obtained at this time, and different flow rates can be obtained after adjusting the drive air intake.
- Flexible application: Different pressure zones can be obtained with different pump types.
- Easy to adjust: Within the pressure range of the pump, the control valve is adjusted to adjust the inlet pressure, and the output hydraulic pressure is infinitely adjusted accordingly.
- Automatic pressure packing: No matter what the pressure of the packing circuit drops, it will automatically start to replenish the leakage pressure and keep the loop pressure constant.
- Safe operation: Driven by gas, no arc and spark, can be used in hazardous places.
19. Steam Jet Pump:
How it works:
When the steam jet pump works, after the steam enters the nozzle, it is ejected at high speed, generating low pressure, sucking the gas in and mixing it in the mixing chamber, and after passing through the expansion tube, the kinetic energy is converted into pressure energy. If the inhaled gas comes from the container and the container is depressurized, it is called a jet vacuum pump.
Performance characteristics:
- The pump has no mechanical moving parts, and is not limited by friction, lubrication, vibration and other conditions, so it can be made into a pump with a large pumping capacity. As long as the construction material of the pump is properly selected, it is extremely beneficial for the exclusion of corrosive gases, gases containing mechanical impurities, and water vapor.
- The structure is simple, light weight, and occupies a small area.
- The working steam pressure is 4~9×105Pa, which is a water vapor source in general metallurgy, chemical industry, medicine and other enterprises.