A metering pump is a type of reciprocating pump, belonging to the positive displacement pump. Simply understood, it is a needle cylinder that injects needles. The output quantity is related to the speed of suction and discharge (pump reciprocating times), the length of pulling and pushing (pump stroke), and the thickness of the needle cylinder (pump plunger diameter). Below, the manufacturer of the metering pump will explain to you the reasons and solutions for the motor failure of the metering pump.

1. Reasons and solutions for inability to discharge or insufficient discharge:

(1) The suction pipeline is blocked or the suction pipeline valve is not open; Solution: Check the suction pipe, filter, and open the valve.

(2) Air leakage in the suction pipeline; Solution: Seal the leaking area tightly.

(3) The suction pipe is too long and there are many sharp turns; Solution: Thicken the suction pipe to reduce sharp turns.

(4) The suction or discharge valve is damaged or foreign objects fall into it, causing the valve surface to be poorly sealed; Solution: Check the sealing of the valve and replace the valve and valve seat if necessary.

(5) Residual gas in the diaphragm chamber; Solution: refill with oil and remove gas.

(6) Leakage or oil leakage at the oil filling valve group or diaphragm chamber; Solution: Identify the leaking area and seal it tightly.

(7) Abnormal operation of safety valves and compensation valves; Solution: Re adjust.

(8) The oil in the oil replenishment system has impurities, the valve is padded, and the seal is not tight; Solution: Replace with clean oil.

(9) Severe leakage at the plunger seal; Solution: Replace the plunger seal.

(10) Insufficient or unstable motor speed; Solution: Stabilize the motor speed.

(11) The suction liquid level is too low; Solution: Adjust the suction liquid level height.

(12) Filter blockage; Solution: Clear the filter.

(13) High material viscosity; Solution: Heat up the liquid, reduce material viscosity, increase pipe diameter, and reduce pipe length.

(14) Calibration system error; Solution: Recalibrate.

(15) The motor does not rotate; Solution: Check the power supply and ensure that the fuses and contacts are in good condition.

2. Reasons and solutions for pump pressure not meeting performance parameters:

(1) Damaged suction and discharge valves; Solution: Replace the valve with a new one.

(2) Severe leakage at the plunger seal; Solution: Replace the plunger seal.

(3) Insufficient sealing at the diaphragm or discharge pipe joint; Solution: Identify the leaking area and seal it tightly.

3. Reasons and solutions for the decrease in measurement accuracy:

(1) Same as items (4) to (11) in item 1 that cannot be drained or have insufficient drainage; Solution: Same as items (4) to (11) in item 1.

(2) Plunger zero drift; Solution: Readjust the zero point of the plunger.

4. Reasons and treatment methods for overheating of parts:

(1) Excessive or insufficient oil in the transmission mechanism oil tank, with impurities in the oil; Solution: Replace with new oil to ensure the appropriate amount of oil.

(2) Poor lubrication of each motion pair; Solution: Check and clean all oil holes.

(3) The packing is pressed too tightly; Solution: Adjust the packing gland.

5. Reasons and handling methods for impact noise inside the pump:

(1) Severe friction between each pair of motion; Solution: Adjust or replace parts.

(2) The valve lift is too high; Solution: Adjust the lift height to avoid valve lag.

6. Reasons and treatment methods for excessive leakage of pump packing box:

(1) Measures to eliminate shaft bending: Straighten the shaft or replace it as required.

(2) Measures to eliminate misalignment between the coupling or pump and drive device: Check the alignment and re align if necessary.

(3) Incorrect lubrication of bearings or measures to eliminate bearing wear: Check and replace as required.

7. Reasons and solutions for high bearing temperature:

(1) Measures to eliminate shaft bending: Straighten the shaft or replace it as required.

(2) Measures to eliminate misalignment between the coupling or pump and drive device: Check the alignment and re align if necessary.

(3) Incorrect lubrication of bearings or measures to eliminate bearing wear: Check and replace as required.

(4) Measures to eliminate excessive stress on the pipeline on the pump casing: Relieve the stress and consult with the manufacturer's representative. After stress relief, check the alignment.

(5) Measures to eliminate excessive lubricant: Remove the plug and allow the excess grease to be automatically discharged. If it is an oil lubricated pump, drain the oil to the correct level.

8. Reasons and treatment methods for overheating of water pump packing box:

(1) The packing or seal in the pump packing box is worn, causing air to leak into the pump casing. Measures to eliminate this: Check the packing or seal and replace it as needed. Check if lubrication is normal.

(2) The water pump packing box does not have the correct packing (insufficient packing, incorrect insertion or running in, packing too tight). Elimination measures: Check the packing and reinstall the packing box.

(3) Measures to eliminate design issues with water pump packing or mechanical seals: consult the manufacturer.

(4) Measures to eliminate damage to the mechanical seal of the water pump: Check and replace it as required. Consult the manufacturer.

(5) Measures to eliminate scratches on the water pump shaft sleeve: repair, remachine or replace as required.

(6) The water pump packing is too tight or the mechanical seal is not properly adjusted. Elimination measures: Check and adjust the packing, and replace it as required. Adjust the mechanical seal (refer to the manufacturer's instructions provided with the water pump or consult the manufacturer).