Can a chemical pump feed pump be reversed?

　　In the chemical field, most of the raw materials are transported through the pipeline, in some specific cases, but also need to be pressurized through the pressurized pump for pressurized transport, but in the actual production process, found that the pressurized pump is often easy to damage, especially in the raw materials pressurized transport to the high out of the pipeline, due to the pipeline is not set up back to the pipeline, the pipeline in the high level of difference between the liquid in the pump stops dropping, and to promote the pump reversed, long time to promote the reversal, will appear! Pump impeller loosening, seal leakage, pump shaft breakage, impeller jamming and many other accidents.

　　Can the chemical pump feed pump reverse?

　　Can not.

　　First, the reason for chemical pump reversal:

　　Chemical pump reversal is also divided into active reversal and passive reversal, and the hazards caused by each are not the same.

　　Active reversal, refers to the motor drag chemical pump reversal, mainly chemical pump motor wiring reversal.

　　Passive reversal, refers to the chemical pump drag motor reversal, chemical pump export pipeline liquid flow back into the inlet, causing the chemical pump reversal, thus driving the motor reversal (at this time also need to consider whether the motor is out of power).

　　Second, the main hazards of chemical pump reversal:

　　1. Mechanical seals with rotation requirements may be damaged.

　　2. The shaft sleeve lock nut and impeller lock nut (also called impeller and cap) with the requirement of rotation may be loosened, and the impact will not be great if the pin is used to connect. Passive reversal, refers to the pump drag motor reversal, the pump outlet pipeline liquid backflow into the inlet, causing the pump reversal, thus driving the motor reversal (at this time also need to consider whether the motor is out of power).

　　3. Pumps with balance disk or balance drum may damage the balance disk or balance drum.

　　4. Causing water hammer and damaging the pump structure.

　　5. Chemical pumps are easy to reach resonance speed, damaging pump equipment

　　Third, chemical pump reversal precautions:

　　1. After the chemical pump is tripped or shut down, closely monitor the status of the outlet door of the shut down chemical pump, the outlet pressure, rotation speed and flow rate, and closely monitor the change of the water level of the steam packet, so as to prevent the furnace from being jumped due to the low level of the steam packet caused by the reversal of the chemical pump to grab water.

　　2. When the chemical pump is found to be reversed, keep the lubricating oil system in safe operation, closely monitor the vibration and temperature change of the bearings, and immediately stop all the chemical pumps and take measures to depressurize the water supply system so that the reversed chemical pumps can be safely put out of operation.

　　3. When the chemical pump is inverted, it should immediately notify the maintenance to close the electric outlet door manually and close the manual door of the operating pump to supply reheat desuperheating water, and reduce the pressure of the feed water system appropriately when there is no other abnormal change in the parameters of the inverted chemical pump to prevent the chemical pump from dragging the small steam engine to overspeed.

　　4. If the chemical pump still reverses after the electric outlet door is closed, report to the relevant director and apply for shutdown, and it is strictly prohibited to eliminate the reversal by forcibly starting and stopping the chemical pump, and it is not allowed to close the inlet door of the front pump and the recirculation door to prevent the low-pressure system from being overpressurized.

　　5. If the reversal of the chemical pump seriously jeopardizes the safety of the equipment, it should decisively stop the operation of other chemical pumps, keep the reversal of the chemical pump in safe operation, and promptly notify the maintenance treatment.