Centrifugal explosion-proof stainless steel pump test preparation and load test
Centrifugal explosion-proof stainless steel pumps used in chemical, industrial, petrochemical, and coal mines are mostly classified into multi-stage pumps, chemical pumps, pipeline centrifugal pumps, double-suction split centrifugal pumps, pipeline pumps, etc. So before the test run, what preparations should we make to make it work normally when it is put into work?
Explosion-proof stainless steel pump
Centrifugal explosion-proof stainless steel pump preparation before commissioning:
(1) Check the surface of the foundation to meet the requirements; check the anchor bolts and tighten them in place; the alignment accuracy of the two shafts meets the specified requirements.
(2) The direction of rotation of the motor should be consistent with the direction of rotation of the pump; the insulation of the motor should comply with the regulations; the crank should be flexible and free of abnormal phenomena.
(3) Pressure gauges and vacuum gauges for electrical instruments and pumps should be sensitive and accurate, and valves should be flexible and reliable.
(4) For centrifugal pumps with liquid temperature higher than 120℃, to ensure reliable lubrication of bearings, the bearing parts should be cooled.
(5) The mechanical seal should be cooled, flushed, and transported materials that are easy to crystallize. The crystals on the sealing part should be cleaned up before the pump restarts to avoid affecting the sealing effect or damaging the sealing surface; the assembly of the mechanical seal should meet the specified requirements.
(6) For pumps with packing seals, the tightness of the packing should be appropriate; the cooling liquid sealing ring should be aligned with the cooling pipe mouth, and the cooling liquid should be unobstructed.
Centrifugal explosion-proof stainless steel pump load test run:
(1) The requirements for filling, replacing, and exhausting the pump should be carried out in accordance with the technical documents.
(2) Before starting positive displacement pumps such as reciprocating pumps and screw pumps, the inlet and outlet valves must be opened; when the centrifugal pump is started, the inlet valve should be opened and the outlet valve should be closed. The starting power of the motor will not be too high; After the outlet pressure is stable, immediately open the outlet valve slowly to adjust the required flow and head. When closing the outlet valve, the continuous operation time of the pump should not be too long, otherwise the liquid in the pump will increase in temperature due to the agitation of the impeller.
(3) Open the exhaust valve to fill the entire pump body with liquid. After it is full, the centrifugal pump must close the exhaust valve; jog the pump and confirm the correct steering before starting.
(4) For pumps that are allowed to use water as a medium for trial operation, it is safest to use water for the test. For pumps that transport oil products, the pump cavity is connected to the bearing and the working medium is used as lubricant, and the working medium should be used for testing. Running.
(5) The pump must continuously perform a single-unit test run for 2-4 hours under the rated load; the vortex pump and gear pump have no load (outlet valve fully open) test run, which should be no less than 15 minutes; after normal, it should be at 1/4 of the working pressure , 1/2, 3/4 of the condition of the segmented operation test; the operation time of each segment should be no less than 0.5 h; finally, it should be continuously operated for more than 2-4 hours under the working pressure; before the previous pressure level test operation is not qualified , The test of the latter pressure level should not be carried out.
(6) The high-temperature pump should be preheated before trial operation. The temperature difference between the surface of the pump body and the imported process pipeline with working medium should not exceed 40℃; when the pump body is preheated, the temperature should rise uniformly, and the temperature rise per hour should not exceed 50°C; during the preheating process, crank a half circle every 10 minutes (public number: pump housekeeper); when the temperature exceeds 150°C, crank a half circle every 5 minutes; check the axial expansion of the bolt at the sliding end of the pump body Clearance; open the inlet valve and the vent valve, discharge the gas in the pump, and then close the vent valve after preheating to the specified temperature; for trial operation and stop, the machine should be cranked every 20~30 min until the pump body temperature drops to 50℃ until.
(7) The anchor bolts should be checked for looseness; the rotor and various moving parts should operate normally without abnormal noise and friction; the operation of the auxiliary system should be normal, and the pipeline connection should be firm and leak-free.
(8) The temperature of the sliding bearing should generally not be greater than 70°C; the pump should run continuously for 2 hours under rated conditions.
(9) When stopping the centrifugal pump, gradually close the outlet pipe valve, cut off the power supply, and close the inlet valve. For vortex pumps and gear pumps, turn off the power supply before closing the outlet valve
