The precision gear pump is a rotary pump that relies on the change and movement of the working volume formed between the pump cylinder and the meshing gears to convey liquid or increase pressure. The two closed spaces consist of two gears, the pump body and the front and rear covers. When the gears rotate, the volume of the space on the disengaged side of the gears changes from small to large, forming a vacuum and drawing in liquid, while the volume of the space on the engaged side of the gears changes from large to small, squeezing the liquid into the pipe. The suction and discharge chambers are separated by the meshing line of the two gears. The pressure at the outlet of the gear pump depends entirely on the resistance at the pump outlet.

Structure of precision gear pump.

precision gear pump mainly includes: high pressure quantitative gear pump, high pressure duplex gear pump, lubrication pump, chemical pump, bi-directional gear motor, gear pump with regulator, gear pump with lift valve.

Features of precision gear pump.

(1) Simple structure and low price.

(2) Low working requirements and wide application.

(3) The end cover of the gear and each tooth groove form many fixed sealing workshops, which can only be used as a quantitative pump.

Principle of precision gear pump.

When the gears rotate, the gears originally meshed in the cavity at the inlet end gradually separate and the volume of space becomes larger from small to large, forming a vacuum to absorb fluid. As the gear rotates, the fluid flows out from the gap between the gear and the inner wall of the cavity. The suction and discharge chambers are separated by the meshing lines of the two gears. precision gear pump outlet pressure depends entirely on the resistance at the pump outlet, where the pump flow rate is related to the rotational speed.

Working characteristics of precision gear pump.

Advantages.

1: Simple structure, better workmanship and lower cost.

2: Compared with other kinds of pumps with the same flow rate, the structure is compact and the volume is small.

3: Good self-priming performance. It can reliably achieve self-priming no matter in high or low speed or even in manual situation.

4: Large speed range. Because the transmission part of the pump as well as the gears are basically balanced, no large inertia force will be generated at high rotational speed.

5: Dirt in the oil does not have a serious impact on its work, and it is not easy to bite.

Disadvantages of precision gear pump pair.

1: The working pressure is low. precision gear pump's gears, shafts and bearings are subject to unbalanced pressure and large radial load, which limits the increase of its pressure. Gear pumps are mainly used in low and medium pressure systems.

2: The volumetric efficiency is low. This is due to the large end leakage of the gear pump.

3: The flow pulsation is large, causing large pressure pulsation, which makes the pipeline, valve, etc. produce vibration and noise.

Common failures of precision gear pump.

A. Can not discharge

1: confirm the direction of rotation.

2: confirm whether the valve is closed.

3: check the valve and pressure gauge.

4: check the viscosity of the liquid to run at low speed proportional to the speed of the flow is present, if there is flow, the inflow is insufficient

Second, the flow is not enough

1: confirm whether the valve is closed;.

2: check whether the valve is open.

3: confirm whether the discharge is normal.

4: fasten; a large number of leaks affecting production, should stop running, disassembly and inspection.

5: Check the actual speed of the pump shaft

Third, the sound of strange noise

1：Find the right or fill the grease.

2: Check the motor.

3: Check the bearings and gears.

4: Check the shaft seal.

5: Stop and disassemble to check

Four, the current is too large

1: check downstream equipment and pipelines;.

2: Check the viscosity.

3: check the shaft seal and adjust it appropriately.

4: check after stopping, whether it is too heavy.

5: Check the motor

V. Seal oil leakage

1: readjust;.

2: Tighten the gland bolts appropriately or replace the seal.

3: replace the dynamic and static ring or regrind.

4: Replace the spring

Classification of precision gear pump.

1. According to the form of gear meshing can be divided into: external and internal meshing type

2. According to the curve of tooth shape can be divided into: involute tooth form and cycloid type

3. According to the form of tooth surface can be divided into: straight gear type, helical gear type, herringbone gear type, gear type of circular tooth surface

4. According to the number of meshing gears: two gear type and multi-gear type

5. According to the number of gear stages, it can be divided into: single-stage gear pump and multi-stage gear pump.

Precision gear pump is widely used because of its simple structure, easy processing, small size, light weight, strong self-priming ability and insensitivity to oil pollution.