A pump is a mechanism for conveying fluid or supercharging the fluid. It is mainly used for conveying water, oil, ore pulp, acid and alkali liquid, emulsion, suspending emulsion, gas mixture and liquid metal. It is a common conveying equipment in mining, chemical and metallurgical industries. The following is a series of 19 kinds of pumps (gear pumps, centrifugal pumps, screw pumps, reciprocating pumps, piston pumps, hydraulic plunger pumps, mud pumps, etc.) The dynamic working principle and characteristics of pneumatic diaphragm pump, axial flow pipeline pump, self-priming pump, vortex pump, water ring vacuum pump, roots vacuum pump, rotary vane vacuum pump, air-gas booster pump, gas-liquid booster pump and steam jet pump) are expected to be helpful for the selection and use of pumps.
1- gear pump
Working principle: the teeth of the two gears of the gear pump are separated from each other to form a low pressure, and the liquid is sucked in and sent to the other side along the shell wall. The other two gears close to each other, forming a high pressure to discharge the liquid.
Gear pump
Gear pump
Advantages: simple and compact structure, small volume, light weight, good technology, low price, strong self-priming, insensitive to oil pollution, large speed range, impact load resistance, convenient maintenance, reliable operation.
Disadvantages: unbalanced radial force, large flow pulsation, large noise, low efficiency, poor interchangeability of parts, difficult to repair after wear, unable to be used as variable displacement pump.
2- centrifugal pump
Working principle: when the centrifugal pump works, the liquid fills the pump shell, the impeller rotates at a high speed, and the liquid produces a high speed under the centrifugal force. The high speed liquid passes through the gradually expanded pump shell channel, and the dynamic pressure head changes into the static pressure head.
centrifugal pump
Performance features:
High efficiency and energy saving: the pump has high efficiency hydraulic profile and high working efficiency.
Convenient installation and maintenance: vertical pipeline structure, the pump inlet and outlet can be installed in any position and direction of the pipeline like a valve, which is extremely convenient for installation and maintenance.
Stable operation, safe and reliable: motor shaft and water pump shaft are in-line direct connection, high concentricity, stable operation, safe and reliable.
Stainless steel shaft sleeve: the mechanical seal position of the shaft is relatively easy to be rusted. Once the direct coupled pump shaft is rusted, it is easy to cause mechanical seal failure. The shaft sleeve is inlaid with stainless steel to avoid corrosion, improve the shaft life and reduce the operation and maintenance cost.
Bearing: the bearing at the extension end of the middle and lower shaft of the motor equipped with the pump adopts closed bearing, which is free of maintenance during normal use.
Mechanical seal: the mechanical seal base is generally rubber bellows structure. The traditional mechanical seal on the shaft is changed from the line seal of the O-ring to the two-way face seal of the rubber part, which improves the sealing effect in the clean water medium.
3-multistage centrifugal pump
Working principle: compared with single-stage pump, multi-stage centrifugal pump has more than two impellers, which can absorb and press water in sections and multiple times, so as to lift the water to a very high position, and the lift can be increased or decreased according to the needs.
There are two types of multistage centrifugal pump, vertical and horizontal. The shaft of multistage centrifugal pump is equipped with two impellers in series. Compared with the general single-stage centrifugal pump, it can also achieve higher lift.
Multistage centrifugal pump
Performance characteristics: multi-stage pump is mainly used for mine drainage, urban and factory water supply. Compared with piston pump, diaphragm pump and other reciprocating pump, it can also pump large flow. Multistage centrifugal pump has high efficiency and can meet the needs of high lift and high flow conditions. It has been widely used in petrochemical, chemical, power, construction, fire protection and other industries.
Because of its particularity, compared with single-stage centrifugal pump, multi-stage centrifugal pump has different and higher technical requirements in design, use, maintenance and other aspects.
4- screw pump
Working principle: the twin screw pump is very similar to the gear pump. One screw rotates to drive the other screw. The liquid is intercepted in the meshing chamber, pushed along the rod axis, and then squeezed out to the center.
Screw pump
Screw pump
Screw pump
Advantages of screw pump:
Wide range of pressure and flow. The pressure is about 3.4-340 kgf / cm2, and the flow rate can reach 100 cm3 / min;
The type and viscosity of the liquid transported are wide, and the concentrator can be used to transport the collector, flocculant, etc;
Because the inertia force of the rotating parts in the pump is low, a very high speed can be used;
Good suction performance, self-priming ability;
The flow rate is uniform and continuous, the vibration is small, and the noise is low;
Compared with other rotary pumps, it is less sensitive to incoming gas and dirt;
Solid structure, easy to install and maintain.
Disadvantages of screw pump: the processing and assembly requirements of screw are higher; the performance of pump is more sensitive to the change of liquid viscosity.
5- reciprocating pump
Working principle: 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 drawn in; when the piston moves to the left, the pressure in the cavity increases, the upper valve is jacked up, the lower valve is pressed down, and the liquid is discharged.
reciprocating pump
reciprocating pump
Advantages of reciprocating pump:
A high discharge pressure can be obtained, and the flow rate is independent of the pressure, with good suction performance and high efficiency. Among them, the steam reciprocating pump can reach 80% ~ 95%;
In principle, it can transport any medium, almost not limited by the physical or chemical properties of the medium;
The performance of the pump does not change with the pressure and the viscosity of the delivery medium.
Disadvantages of reciprocating pump: flow is not very stable. Compared with the centrifugal pump under the same flow rate, it is huge; the mechanism is complex; the amount of capital is large; it is not easy to maintain, etc.
6-double acting reciprocating pump
Working principle: when the double action reciprocating pump works, the piston moves to the right, sucks liquid from the left to the bottom, and discharges liquid from the right to the top. Move the piston to the left, suck the liquid at the right bottom and drain the liquid at the left top. Piston reciprocating once, there are two suction, discharge, flow more uniform.
Double acting reciprocating pump
7- piston pump
Working principle: the piston pump is also called the electric reciprocating pump, which is divided into single cylinder and multi cylinder from the structure. When the piston pump works, the reciprocating action of the piston in the cylinder makes the volume of the cylinder change repeatedly, so as to suction and discharge the fluid.
Piston pump
Performance characteristics of piston pump:
The piston pump is suitable for high pressure and small flow situations, especially when the flow is less than 100m3 / h and the discharge pressure is greater than 9.8MPa, which shows its high efficiency and good operation performance.
It has good suction performance and can pump liquid with different medium and viscosity. It can be used for water injection, oil injection and oil production in oil field and coal seam. If the flow passage parts are made of stainless steel, corrosive liquid can be delivered. In addition, according to different structural materials, it can also transport high temperature tar, slime, high concentration mortar, high viscosity liquid, etc.
Piston pump is widely used in petrochemical industry, machinery manufacturing industry, papermaking, food processing, pharmaceutical production, etc.
8-hydraulic plunger pump
Working principle: hydraulic plunger pump or solid pump, driven by hydraulic power pack, the hydraulic cylinder pushes the conveying cylinder, and outputs the materials in the conveying cylinder to the pipeline.
hydraulic piston pump
Generally, it is divided into single plunger and double plunger. The basic principle of plunger pump is very simple. This pump uses relatively large momentum of moving water body to pump relatively small volume of water to high place.
Hydraulic plunger pump is widely used in sewage treatment, solid waste treatment, mine metallurgy, dredging, petrochemical, power plant, cement industry and other fields.
9- mud pump
Working principle: the commonly used mud pump is piston type or plunger type. The power machine drives the crankshaft of the pump to rotate. The crankshaft drives the piston or plunger to do reciprocating motion in the pump cylinder through the crosshead. Under the alternate action of suction and discharge valves, the purpose of pressing and circulating flushing liquid is realized.
mud pump
Mud pump is a kind of machine that can deliver mud or water to drill hole in the process of drilling. It is an important part of drilling equipment.
In the common positive circulation drilling, the surface flushing medium, water, mud or polymer flushing fluid, is directly sent to the bottom of the drill bit through the high-pressure hose, faucet and the central hole of the drill string under a certain pressure, so as to cool the drill bit, remove the cuttings cut and transport them to the surface.
10 - pneumatic diaphragm pump
Working principle: in order to keep the movable column from contacting with corrosive material and liquid directly when the pneumatic diaphragm pump is working, the cylinder cavity and liquid material are separated by diaphragm, which is essentially the principle of reciprocating pump. Pneumatic diaphragm pump has four materials: engineering plastics, aluminum alloy, cast iron, stainless steel.
Pneumatic diaphragm pump
Pneumatic diaphragm pump
Pneumatic diaphragm pump
Performance characteristics of pneumatic diaphragm pump
Using compressed air as power source, it can be used for various corrosive liquids. Different materials can be used according to different liquid media to meet the needs of different users.
The pump will not overheat: the compressed air is used as the power, which is a process of expansion and heat absorption when exhausting. When the pneumatic pump is working, the temperature is reduced, and no harmful gas is discharged.
No electric spark will be generated: pneumatic diaphragm pump does not use electric power as power, and electrostatic spark is prevented after grounding
It can pass through the liquid containing particles: because the volume type work and the inlet is a ball valve, it is not easy to be blocked.
Very low shearing force on materials: how to suck in and how to spit out when working, so the minimum agitation on materials is applicable to the transportation of unstable materials
The flow can be adjusted, and a throttle valve can be installed at the outlet of the material to adjust the flow.
It has self-priming function.
It can run empty without danger.
Can dive to work.
It can transport a wide range of fluids, from low viscosity to high viscosity, from corrosive to viscous.
No complex control system, no cables, fuses, etc.
Small size, light weight, easy to move.
No need for lubrication, so it is easy to maintain and will not pollute the working environment due to leakage.
The pump is always efficient and will not be reduced due to wear.
100% energy utilization. When the outlet is closed, the pump will stop automatically, and the equipment will move, wear, overload and heat up
There is no dynamic seal, so the maintenance is simple and the leakage is avoided. There is no dead point at work.
11 - axial flow pipeline pump
Working principle: the impeller of the axial-flow pipeline pump is designed to be axial-flow type with high speed. If the motor power, impeller diameter and pipeline diameter are large enough, the flow can be large.
Axial flow pipeline pump
Performance characteristics of axial flow pipeline pump:
The pipeline pump has compact structure, integrated pump and small volume. Its vertical structure has the advantages of small installation area, stable operation and no adjustment for installation.
The inlet and outlet of the pump are designed with the same flange and located in the same center online. It 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 dimension is short, which makes the pump run more smoothly and has low noise.
The traditional shaft seal method is cancelled to avoid the leakage of the transmission medium, so it has the obvious characteristics of no leakage.
12- self priming pump
Working principle: before starting the pump, fill the pump shell with water (or there is water in the pump shell). After startup, the impeller rotates at a high speed so that the water in the impeller channel flows to the volute. At this time, a vacuum is formed at the inlet, so that the check valve of the water inlet is opened, and the air in the suction pipe enters the pump and reaches the outer edge through the impeller channel.
Self priming pump
Performance characteristics of self-priming pump:
The self-priming pump belongs to the self-priming centrifugal pump, which has the advantages of compact structure, convenient operation, stable operation, easy maintenance, high efficiency, long service life and strong self-priming ability.
The pipeline does not need to be installed with bottom valve. Before operation, it is only necessary to ensure that the pump body is stored with quantitative liquid extraction. Different materials of self-priming pump can be used for different liquids.
13- vortex pump
Working principle: the liquid in the groove of the vane of the vortex pump is thrown to the flow passage by centrifugal force and pressurized once; the liquid in the flow passage is caused by