Introduction of water jet vacuum pump used in pharmaceutical equipment

1. Working principle

The working principle of the water jet vacuum pump, the working medium water with a certain pressure, through the nozzle to the suction chamber at high speed, the pressure of the water can be changed into kinetic energy, forming a high-speed jet; The gas in the suction chamber is forcibly carried and mixed by a high-speed jet, forming a gas-liquid mixed flow, which enters the diffuser, thus reducing the pressure of the suction chamber and forming a vacuum. In the expansion section of the diffuser, the kinetic energy of the mixed jet is transformed into pressure energy, the speed is reduced, the pressure is increased, the gas is further compressed, and the gas is discharged out of the pump together with water, and the gas is separated in the water tank, and the gas is released into the atmosphere. The water is recycled by the pump, and the purpose of pumping vacuum is achieved again and again. The nozzle of the single-stage water injection pump can be a single nozzle structure composed of a decreasing nozzle, or a multi-nozzle structure with multiple holes on a hole plate.

2. Running characteristics

The working system of water jet vacuum pump is composed of water pump, water jet pump, pipeline, valve, water vapor separator and test instrument, etc. The common system has two kinds of installation methods: vertical and horizontal.

The pumping capacity of the water jet pump is between 5 and 800m3/h, and the ultimate vacuum degree of the single-stage pump can reach 3000 Pa (23 brackets). In order to improve the vacuum degree, the steam water can be operated in series. If the first-stage water jet pump is used with the three-stage steam jet pump, the four-stage water jet jet pump unit is formed, and the ultimate pressure can reach 20Pa (0.15mmHg). In order to prevent the vacuum pump from being corroded by the pumping medium, the anticorrosive injection pump can be selected. Centrifugal pumps can be made of reinforced polypropylene (RPP), stainless steel, fluorine alloy, glass fiber reinforced plastic; The injection pump can be made of stainless steel, cast iron internally rolled polyethylene (PE) or polytrifluoro-vinyl chloride steel lined with ceramic, and the nozzle is polytetrafluoroethylene or ceramic.