Jiangsu Weigu fluid introduction: screw vacuum pump cleaning operation steps

The purification and cleaning treatment of dry screw vacuum pump is to remove the gas and compressed steam remaining in the dry screw

 vacuum pump during the compression process. When the dry screw vacuum pump restarts, these residual substances have the potential to

 cause motor overload, which may produce excessive friction load or damage the screw or pump body. Therefore, in the case of a considerable 

amount of unclean substances in the pump, the pump should be cleared.

The cleaning operation of screw vacuum pump is mainly through cooling purification and cleaning purification.

First, cooling and purification:

The purpose of cooling purification is to cool the inside of the pump body and the screw. When the pump is running, the screw rotates so that

 the pumped gas enters the pump chamber and is compressed to the exhaust end, and the temperature of the gas will rise rapidly due to thermal compression. In order to prevent the pump from being damaged, this heat must be removed immediately.

Usually use the air in the atmosphere as a cooling purification medium, when the pumped process gas is not suitable for air purification, it is necessary to use other cooling media such as nitrogen, clean and dry air. For standard pumps, an interface is provided near the exhaust end of the pump body.

Second, cleaning and purification:

Cleaning and purification is necessary to clean the pump chamber before stopping the pump. Before stopping the pump, close the main valve on the pump inlet pipe and inject nitrogen or clean air for 20-30 minutes in order to clean the viscous process material or process gas from the inside surface of the pump. This is especially important when pumping corrosive or toxic gases, or sticky materials such as resins.

Steam flushing is an effective method to remove the residual compressed gas material. If residual compressed material accumulates, make sure that the dry screw vacuum pump does not put too much pressure on the motor rotation. Especially for some active substances, such as oligomers, monomers, polymers, resins and so on, the correct flushing to remove, has a good effect.

The purpose of purification and cleaning is that after the operation of the screw vacuum pump, the viscous substances gather in the pump, if not cleaned and purified in time, it may cause the motor load to increase after the pump operation, and the motor current to increase, resulting in too fast damage to the pump. Or corrosive gases gather in the pump, causing the coating of the pump part of the flow to fall off, affecting the pump.

There are two kinds of purification and cleaning substances, one is an inert gas, such as nitrogen, argon and so on. One is steam. There are two kinds of purification and cleaning opportunities, one is before the operation, the other is after the operation, before and after are essential. Whether it is inert gas or steam, its pressure should be 1 kg /cm2, not too high, not too low. Too high will damage the skeleton oil seal, too low will not work.

Controls

Insert inert gas or steam at 1 kg /cm2 pressure into the valve. Close the intake valve, open the charge valve, open the valve. Start the pump. 30 minutes or so. The time depends on the accumulation of material in the pump. After the shutdown, rotate the pump by hand, whether it is smooth, smooth words to complete, not smooth words to repeat 2-3 times. Then close the charging valve, start the pump and run for 20 minutes, empty the liquid in the pump, until there is no liquid discharge at the exhaust port, stop. Close the valve, start the pump, and check whether the pump is running normally. The cooling water should also be turned on at this time. Dry screw vacuum pump empty operation, after the cleaning and purification process is completed, the pump needs to be empty for 20-30 minutes to completely empty the residue in the pump, so as not to affect the normal operation of the next time.

Cleaning substance

1) Generally speaking, the unclean substances in the pump are cleaned using 99.99% dry air or nitrogen. This is the most effective substance.

2) If the above substances can not clean the unclean in the screw vacuum pump, it is recommended to use the liquid that has the decomposition effect of the unclean matter (as long as these liquids are not corrosive), can be used. Cleaning method as described above.