In order to avoid the force and torque generated by the weight of the pipe, the valve and the thermal stress of the pipe exceeding the maximum allowable external load of the pump inlet and outlet, a pipe rack shall be provided on the suction and discharge pipes of the pump.
The maximum allowable load on the pump nozzle should be provided by the pump manufacturer.
For the vertical inlet or vertical outlet pump, in order to reduce the force on the pump nozzle, the pipeline above the nozzle shall be provided with a pipe rack. The plane position should be as close as possible to the nozzle. The pipe longitudinal beam can be used to support the pipeline, so the pump is often used. Arranged under the pipe gallery.
In order to improve the pump’s suction performance, the pump suction line should be as short as possible, with as few turns as possible (the elbow is preferably a large radius of curvature) to reduce the pipe resistance loss.
In order to prevent the pump from cavitation, the pump suction line should avoid the accumulation of gas in the capsule part. If it is unavoidable, the DN15 or DN20 exhaust valve should be installed in the capsule.
When the suction pipe of the pump is in the vertical direction, if a different diameter pipe is arranged on the suction pipe, an eccentric reducer should be arranged to avoid the formation of the air bag.
For liquids with a density of 650Kg/m3, such as liquefied petroleum gas, liquid ammonia, etc., the pump suction pipe should have a slope of 1/10~1/100, so that the gas generated by gasification can be returned to the tank to avoid The pump produces cavitation.
At the inlet of the single suction pump, it is best to arrange a straight pipe of about 3 times the diameter of the inlet.
For double suction pumps, in order to avoid the cavitation of the two-way suction horizontal centrifugal pump, the double suction pipes should be arranged symmetrically to ensure uniform flow distribution on both sides. The vertical pipe is connected directly through the elbow, but the axis of the pump must be perpendicular to the plane in which the elbow is located. At this time, the import piping requirements are as short as possible, the elbows are connected to the different diameter pipes, and then the inlet flanges are connected. Under other conditions, there should be a straight pipe section of not less than 3 pipe diameters before the pump inlet.
Use a drain valve between the shut-off valve and the check valve at the pump outlet. When the pipe diameter is larger than DN50, the net valve can also be installed in the bonnet of the check valve. The inlet and outlet valves of the same specification pump should use the same elevation as much as possible.
The weight of the valve on the inlet and outlet lines of the non-metallic pump must not be pressed on the pump body. The pipe rack should be installed to prevent the pipeline before and after twisting the valve when the pump body and the switch valve are crushed. The exhaust pipe of the steam reciprocating pump should be less curved, and a discharge pipe should be provided at a place where condensed water may accumulate, and a muffler should be installed for a large amount of emptying. The inlet pipe should be provided with a condensate drain pipe in front of the inlet valve to prevent water from hitting the cylinder.
Steam reciprocating pumps generally have large vibrations during operation, and the lines connected to the pump should be well fixed.
When the distance between the center line of the pump outlet and the center line of the pipe column is greater than 0.6m, the swing-type check valve on the outlet line should be placed in a horizontal position. At this time, it is not allowed to install a net valve on the valve cover.
When the pipeline rack is above the pump and the motor, the pipeline must have sufficient height to not affect the lifting of the lifting equipment. The pipeline carrying the corrosive liquid should not be placed above the motive equipment.
The net distance from the bottom of the pipeline to the floor of the lower pipeline of the pipe gallery should not be less than 4m to meet the maintenance requirements.
When the pipeline rack is above the pump body, the clearance height of the bottom of the pipeline from the ground shall be not less than 2.2m.
Post time: Oct-17-2019