8 common faults of plunger pumps and their repair methods

Plunger pump common faults and their repair methods

Plunger pump is an important power element in the Hydraulic System, and its Working Principle is to use the plunger reciprocating motion in the cyLinder barrel to transport or pressurize the liquid. Plunger pumps have the advantages of compact structure, high efficiency, small pressure pulsation, etc., and are widely used in engineering machinery, automobiles, ships and other fields.

Plunger pumps in the long-term use of the process will appear a variety of faults, affecting its normal work. Common failures and maintenance methods are as follows:

1. No flow or insufficient flow after the pump starts, large pressure pulsation, and strong pipeline shaking

Reason:

The air in the pump chamber is not discharged

Poor sealing of the plunger inlet and outlet valves

Suction filter cLogged

Pressure Relief valve or relief valve failure

The suction pipe is too thin and too long, and the liquid level in the water tank is low

Maintenance method:

Venting

Replace or repair ram inlet drain valve

Clean the suction filter

Check and eliminate pressure relief valve or relief valve failure

Replace or enlarge the suction hose to raise the tank level

2. flow without pressure or insufficient pressure

Cause:

Poor sealing of manual pressure relief valve, fatigue of regulator spring

Spray nozzle hole wear

Repair method:

Repair or replace manual pressure relief valve

Replace the nozzle

3. noisy operation, loud impact sound

Cause:

The crankshaft crankshaft and axial tile are badly worn, the clearance is too large, the connecting rod screws are loose

Pump debris, gear damage

Insufficient suction

Repair method:

Replace the shaft tile or crankshaft, tighten the connecting rod screws

Clean the pump body, replace the gear

Check the suction pipeline and remove the blockage

4. Increased oil temperature, abnormal heat

Cause:

Insufficient or too much oil, dirty oil, oil number does not match, improper viscosity

Transmission parts of the gap is too large, accessory parts of the friction is too large, long running time

Maintenance method:

Add or replace the oil according to regulations

Check and adjust the clearance of transmission parts, replace the worn parts.

5. Sudden increase in pump pressure

Cause:

Safety valve or relief valve failure, system failure

Repair method:

Check and repair safety valve or relief valve

Troubleshooting the system

6. Oil leakage from lubrication area

Cause:

Cylinder wall pulling hair, piston ring damage

Repair method:

Repair or replace the cylinder, piston ring

7. High case temperature

Cause:

Insufficient or too much lubricating oil, dirty lubricating oil, damaged axial tile or crankshaft hair pulling

Repair method:

Add or replace lubricating oil

Clean the lubrication system, replace the axle shaft or crankshaft.

8. Severe leakage at plunger seal

Cause:

Worn or damaged seals, severe pulling and scratching of the plunger surface.

Repair Method:

Replace seal.

Replace or repair the plunger.

Notes：

Before servicing the plunger pump, read the instruction manual carefully to understand the structure and working principle of the pump.

When disassembling and installing the plunger pump, it should be carried out in strict accordance with the operating procedures to avoid damaging the parts.

The parts used for repair should be original parts or parts that meet the quality requirements.

After the repair is completed, test run should be carried out to check whether the performance of the pump meets the requirements.

In addition, in order to prevent the plunger pump failure, should also pay attention to the following matters:

Regularly check and maintain the Piston Pump and replace worn or damaged parts in time.

Use hydraulic oil that meets the quality requirements and replace the hydraulic oil regularly.

Keep the hydraulic system clean and prevent impurities from entering the pump.

Avoid overloading the pump.