What are the common failures of chemical pumps? Chemical pump fault repair treatment method

　　Chemical centrifugal pump common failure

　　1、Pump does not suck water

　　Failure analysis:

　　Suction valve with debris or not open, or suction pipe blockage

　　Poor sealing of piping system

　　Suction of air from the shaft seal

　　Irrigation pump system failure

　　Solution:

　　Open the suction valve, remove debris and unblock the suction pipe.

　　Inspect the piping, especially at the connecting flange of the sectional pressure test, and plug the leakage.

　　Replace the shaft seal and press the packing seal

　　Check and repair the irrigation pump system

　　2, the pump can not start

　　Failure analysis:

　　Failure of the prime mover (including power supply).

　　Pump jammed

　　Packing box is pressed too tight.

　　Discharge valve is not closed.

　　Solution:

　　Check power supply and prime mover condition.

　　Re-check coupling condition.

　　Loosen the packing.

　　Pipe inlet and outlet valves, start again.

　　3, the pump does not discharge liquid

　　Failure analysis:

　　Insufficient filling of the pump (or pump gas is not discharged).

　　Pump steering is not right.

　　Pump speed is too low.

　　Strainer, suction pipe clogging.

　　The suction height is too high, or the suction port liquid supply is insufficient, resulting in suction vacuum.

　　Solution:

　　Refill the pump;.

　　Determine the direction of pump rotation again; and

　　Check the idling speed of the motor, check the reduction ratio of the reducer, and determine whether the pump speed is in accordance with the design speed;.

　　Clean the strainer and unclog the suction pipe.

　　Adjust the suction port pipeline, higher than the pump inlet, adjust the pump's upper liquid supply system to ensure adequate supply of media.

　　4、Pump discharging liquid after the interruption

　　Failure analysis:

　　Leakage of gas in the suction line.

　　The gas on the suction side is not exhausted when filling the pump.

　　The suction side is suddenly blocked by a foreign body, or the suction port filter is blocked.

　　Dehydration of the suction pipe, a large amount of gas inhalation

　　Solution:

　　Check the sealing condition of the connection and stuffing box on the suction side.

　　Refill the pump.

　　Stop the pump, clean the filter element and unclog the suction line.

　　Check whether the suction line is ruptured, and whether the valve on the parallel inlet pipeline is open (not commonly used pipeline).

　　5, insufficient flow

　　Failure analysis:

　　Increase in the net head of the system.

　　Increase in resistance loss;.

　　Excessive wear and tear of the mouth ring and impeller.

　　Liquid leakage elsewhere; and

　　Pump impeller clogged, worn, corroded.

　　Solution:

　　Check the liquid level height and system pressure.

　　Inspect the pipeline and check valve etc. for any faults.

　　Replace the mouth ring and impeller.

　　Check the shaft seal and other places.

　　Cleaning, inspection, and replacement.

　　6、Insufficient head

　　Failure analysis:

　　Reverse impeller installation (double-suction pump).

　　Liquid density, viscosity and design conditions do not match.

　　Operation flow is too large.

　　Solution:

　　Check the impeller.

　　Check the relevant physical properties.

　　Mediate the valve, reduce the amount of sulfur.

　　7、Operation overload

　　Failure analysis:

　　Poor quality of motive power, stator-rotor friction;

　　Friction between impeller and wear ring, impeller and pump casing.

　　Liquid density increase;

　　Packing too tight or dry friction.

　　Damaged bearings.

　　Excessive speed

　　Bending of the pump shaft

　　Failure of the axial force equalizer.

　　Poorly centered couplings or too little axial clearance.

　　Conveying liquid viscosity is too high or density is too high.

　　Solution:

　　Check and replace the motor.

　　Check the pump parts and repair them.

　　Check the density.

　　Loosen packings, check water seal tubes.

　　Inspect & replace bearings;.

　　Check prime mover speed and power supply.

　　Align the pump shaft.

　　Check balance air and return pipe for clogging.

　　Check the coupling and adjust the centering;

　　Replace the high-power motor.

　　8, pump vibration or noise exceeds the standard

　　Failure analysis:

　　Loose ground bolts or base welding is unqualified.

　　Pump flow corrosion (flow rate is too large, the suction resistance increases or the liquid operating temperature is too high).

　　Surge of the pump (system net head pressure is higher than the pump shutdown pressure)

　　Impeller damage or foreign objects.

　　Solution:

　　Tighten ground bolts, weld to base recheck, and if necessary, base reweld.

　　Check the cause and eliminate the system.

　　Check the discharge also for and whether the pressure is too high.

　　Disassemble the pump body to check, replace and remove foreign matter.

　　9、Bearing overheating

　　Failure analysis:

　　Bearing assembly is unqualified.

　　Insufficient lubricant, poor oil quality or aging.

　　Insufficient cooling water or broken circuit.

　　Solution:

　　Check, adjust;

　　Add enough oil or change the oil.

　　Check and increase the amount of water.

　　10, shaft seal overheating

　　Failure analysis:

　　Packing seal is pressed too tightly;

　　Mechanical seal failure.

　　Solution:

　　Adjust the sealing pressure;

　　Check, repair or replace the mechanical seal.

　　Chemical electric submersible pump common failure

　　1, the pump can not start

　　Failure analysis:

　　Power supply voltage is too low to open;

　　Power supply disconnection;

　　Impeller jammed.

　　Cable breakage.

　　The pump is entangled by sea creatures or sea debris.

　　Loose wiring at both ends of the cable.

　　Stator windings burned out.

　　Solution:

　　Adjust the voltage between ±10% of the rated voltage;.

　　Find the cause of power failure.

　　Dismantle the pump and remove debris from the jammer wheel.

　　Check whether the anti-sea creature device is activated and effective, if necessary, put the seabed robot to detect whether there is a foreign body entanglement.

　　Check and reconnect the wires.

　　Start the pump, send manufacturers or maintenance units to replace the winding.

　　2, the pump less water

　　Failure analysis:

　　The head is too high.

　　Pump inlet blockage;

　　Impeller steering error.

　　Impeller wear

　　Worn, leaking port ring; and

　　Pump body leakage.

　　Solution:

　　Adjust the valve. If still can not be solved, to check whether the pump outlet pressure is in line with the design requirements, if necessary, change the pump;

　　Clean the inlet filter, unclog the inlet pipeline.

　　Adjust the phase sequence of the motor.

　　Check the coupling and adjust the centering;

　　Replace the high-power motor.

　　8, pump vibration or noise exceeds the standard

　　Failure analysis:

　　Loose ground bolts or base welding is unqualified.

　　Pump flow corrosion (flow rate is too large, the suction resistance increases or the liquid operating temperature is too high).

　　Surge of the pump (system net head pressure is higher than the pump shutdown pressure)

　　Impeller damage or foreign objects.

　　Solution:

　　Tighten ground bolts, weld to base recheck, and if necessary, base reweld.

　　Check the cause and eliminate the system.

　　Check the discharge also for and whether the pressure is too high.

　　Disassemble the pump body to check, replace and remove foreign matter.

　　9、Bearing overheating

　　Failure analysis:

　　Bearing assembly is unqualified.

　　Insufficient lubricant, poor oil quality or aging.

　　Insufficient cooling water or broken circuit.

　　Solution:

　　Check, adjust;

　　Add enough oil or change the oil.

　　Check and increase the amount of water.

　　10, shaft seal overheating Failure analysis:

　　Chemical screw pumps and gear pumps of common failures

　　1、Pump does not suck liquid

　　Failure analysis:

　　Motor does not rotate.

　　Reverse rotation of electric motor

　　The suction line is clogged and leaking.

　　Suction height exceeds the allowable suction vacuum height

　　Dielectric viscosity is too large.

　　Solution:

　　Check the power supply, line and motor.

　　Adjust the phase sequence of the motor.

　　Check the suction line and filter.

　　Reduce the height of suction up.

　　Give the meson proper heating.

　　2、Insufficient flow

　　Failure analysis:

　　Motor speed is not enough;.

　　Screw (or gear) and pump sleeve wear.

　　The safety valve is damaged or calibrated too low.

　　Solution:

　　Determine whether the rated speed of the motor meets the design requirements, and check whether the electric system voltage meets the motor requirements;.

　　Replace relevant parts.

　　Recalibrate safety valve to meet design requirements. If damaged, replace or repair.

　　3、Pressure fluctuations

　　Failure analysis:

　　Suction piping leakage;

　　Pump screw and pump sleeve is not centrifugal.

　　The safety valve is not calibrated, or the working pressure is too large, so that the safety law is open and closed.

　　Solution:

　　Check the piping and repair it well;

　　Overhaul and adjust or replace.

　　Re-calibrate the safety valve or reduce the working pressure.

　　4, mechanical seal oil leakage

　　Failure analysis:

　　Mechanical seal damage.

　　Seal gland is not pressed flat.

　　Assembly position is not correct.

　　Solution:

　　Replace the mechanical seal.

　　Adjust the sealing gland.

　　Re-assemble according to technical requirements.

　　5、Pump overheating

　　Failure analysis:

　　The pump screw and pump sleeve with too tight;

　　Mechanical seal oil return hole clogging.

　　Dielectric temperature is too high.

　　Solution:

　　Check and adjust the pump screw and pump sleeve clearance, if necessary, to replace the parts;

　　Unclog the oil return hole.

　　Take the necessary measures to reduce the meson temperature.

　　6, pump vibration

　　Failure analysis:

　　Pump and motor is not concentric;

　　There is air in the pump.

　　Screw and pump sleeve is not concentric or large gap.

　　Installation height is too high, cavitation in the pump.

　　Solution:

　　Adjust the position and re-center;

　　Check the suction pipeline, exclude the air leakage parts.

　　Overhaul and adjust or replace.

　　Reduce the installation height.

　　7、Operation overload

　　Failure analysis:

　　Dielectric viscosity is too large.

　　Excluding pipeline blockage;

　　Serious friction between the screw and the pump sleeve.

　　Solution:

　　Appropriate warming of the meson.

　　Stop the pump and unclog the discharge line.

　　Overhaul or replace the relevant parts.

　　Chemical metering pump and reciprocating pump common failure

　　1, the pump does not discharge liquid or pump liquid discharge after interruption

　　Failure analysis:

　　The motor does not rotate.

　　The suction pipe is blocked or the suction valve is not open.

　　Air leakage from the suction pipe

　　The suction valve or discharge valve is damaged or poorly sealed.

　　The oil in the replenishment system has impurities and the seal is not tight.

　　Insufficient or unstable motor speed.

　　Suction fluid level is too low.

　　Solution:

　　Check the power supply, line and motor.

　　Check the inhalation pipe, filter, open the inhalation valve;

　　Check the inhalation pipeline, sealing;

　　Repair the suction valve or discharge valve, replace if necessary;

　　Change clean oil.

　　Check the power distribution system and voltage, stabilize the motor speed.

　　Adjust the suction liquid level.

　　2、Insufficient flow

　　Failure analysis:

　　The suction pipe is too long and has too many bends.

　　Air residue in the diaphragm cavity

　　Replenishment valve or diaphragm cavity and other places leakage of air leakage.

　　Safety valve, compensation valve action is not normal.

　　Serious leakage at the plunger packing.

　　Solution:

　　Thicken the suction pipe and reduce the bends.

　　Refill the liquid and remove the gas.

　　Find out the leaking parts and check the sealing tightly.

　　Readjust safety and compensator valves.

　　Adjust the packing gland or replace the new stuffing box.

　　3、Insufficient pump pressure

　　Failure analysis:

　　Suction valve, discharge valve is damaged;

　　Diaphragm or discharge pipe joint seal is not tight.

　　Solution:

　　Replace the valve with a new one.

　　Find out the leakage parts, overhaul, seal tight.

　　4, measurement accuracy is reduced

　　Failure analysis:

　　Plunger zero drift.

　　Solution:

　　Re-adjust the plunger zero point.

　　5, parts overheating

　　Therefore