Diffusion vacuum pump advantages

For a general diffusion  vacuum pump, the pump body is mostly made into a straight type; for a large pump, a cone-shaped or convex-shaped pump body is also used. Since the cylindrical pump body is easy to process, it is currently used more.

The pump body with the pump port diameter D<250mm is made of seamless steel pipe; the pump body of the large pump is made of 4~10mm thick steel plate rolled into a cylinder, and the weld seam can not leak. The inner wall of the pump should be polished with nickel.liquid ring vacuum pump power industry

The convex cavity pump body can greatly improve the pumping speed without increasing the size of the pump port. The convex cavity pump body changes the straight cylindrical pump body into a partial drum-shaped convex cavity pump body. The processing method is still welded by steel plates. The bottom section of the pump is still the same as the inlet diameter of the pump flange, except that the pump body enlarges the pump chamber at the lower part of the inlet flange, and the enlarged diameter extends to the pump wall where the jet of the second stage nozzle is directed. Due to the convex cavity of the pump body, the space for pumping is enlarged, the guiding ability between the first and second nozzles is increased, and the pumping speed is increased.roots vacuum pump in paper industry

Ultra-high vacuum pump oil is also an important issue. Inappropriate pump wall surface temperature makes oil vapor molecules colliding on the inner surface of the diffusion pump difficult to coagulate. The surface temperature of the oil layer flowing down the pump wall is much higher than the pump wall temperature, which is prone to re-evaporation and form oil vapor reflux. . Therefore, the pump wall cooling efficiency is high. Generally, a spiral copper pipe is welded on the outside of the pump wall or in the form of a water jacket (a spiral wire can also be installed in the middle of the water jacket). The pump cooling location is usually limited to the area where the vapor stream can be injected. This allows the oil condensed from above to be subjected to higher heat before returning to the oil pan, allowing the gas dissolved in the oil to be released, preventing it from mixing into the oil vapor. Into the nozzles at all levels, affecting the vacuum of the pump.roots liquid ring vacuum pump system composition