Introduction of the sealing method of the reactor melt pump

The reactor melt pump is mainly used to transport the medium and high viscosity medium in the vacuum reactor, and is usually used in conjunction with the reactor. The reaction kettle melt pump is also called the kettle bottom pump. Its suction port is designed with a large flange, which can make the high viscosity medium suck in smoothly under vacuum conditions. There are three ways to seal the reactor melt pump. Zhengzhou Bart introduces their characteristics respectively.

Double mechanical seal

The standard double-end mechanical seal is suitable for the inlet from vacuum to 15bar, and the material viscosity from 0.2 to 1,000,000 cP (mPas). The maximum temperature of the material is approximately 300. Higher pressure and temperature require special design.

Material viscosity: 0.2-1,000,000 mPas, maximum working temperature: 300°C (580°F), pump inlet pressure: vacuum-15bar.

Vacuum screw seal with stuffing box

The vacuum spiral seal is a special spiral seal that can be heated into a cooling jacket. The needle valve is used to adjust the return flow to the suction side, so that the blocked melt forms a barrier.

This makes it applicable when the suction side is vacuum. Because it is a dynamic seal, it is usually combined with a packing seal with a buffer solution. This combined seal can also prevent air from entering the reactor when the gear pump is stationary.

Material viscosity: 10-40,000 Pas, maximum working temperature: 450°C (842°F), pump inlet pressure: from vacuum to 40bar.

Vacuum screw seal with lip seal

As another option, vacuum screw seals can also be combined with lip seals. When the pump is briefly stopped, the buffer in the lip seal prevents air from entering the pump through the shaft seal.

Material viscosity: 10-20,000 Pa.s, maximum working temperature: 250°C (527°F), pump inlet pressure: from vacuum to 15bar.

The selection of the sealing method of the melt pump: the melt pump is matched with the extruder, usually screw seal and packing seal; the melt pump is matched with the reaction kettle, usually packing seal, because the reaction kettle is vacuumed, it can be sealed with packing. Prevent it from leaking. Zhengzhou Batte's professional melt pump manufacturer provides melt pump models ranging from 0.5CC to 12000CC, which can meet the production needs of different customers.