Oil Diffusion Pumps
● Oil diffusion pumps attain ultra-high vacuum, and are used as the exhaust system for a wide variety of vacuum processes such as vacuum heat treatment, vacuum evaporation, electric beam welding, and sputtering equipment.
● We also offer pumps with an exhaust rate of 10,000L/sec (without baffles) or higher.
● This is a highly reliable ultra-high vacuum pump with little pressure fluctuation even from bumping in the hydraulic oil.
● It uses no mechanical moving parts for a robust, long lifetime.
● Easy to disassemble design simplifies internal cleaning and inspection work.
Construction and operating principle
As shown on the figure, the oil diffusion pump construction consists of a boiler, multi stage jet assembly, and a cylinder with no mechanical moving mechanism. The working oil is heated in the boiler, vaporized and streams out of each stage of the jet stack at supersonic speed. Gases on the high vacuum (inlet) side of the pump are captured in the jet vapor by diffusion, and are carried from upper to the lower jet stages which compresses them in the process. These pumped gasses are then exhausted through the outlet port to the backing pump (ex. Oil-sealed Rotary Vacuum Pump). The vapor stream from the jet stack is cooled and condensed on the inner walls of pump body, and returned to the boiler. By repetition of this process, evacuation is accomplished. The weir plate provided in the boiler permits return and recirculation of the working fluid, allowing the fractional distillation of the fluid to be a continuous process.