5 Tips to understanding how a turbo pump works

If you are looking to purchase a turbo pump, you can start your search by looking at this turbo pumps list. Turbo pumps work on the principle that you can move gas molecules in a particular direction by having them collide with a moving solid surface. A fast spinning fan rotor hits the gas molecules from the inlet of the pump towards the outlet creating and maintaining a vacuum. Here are five tips for understanding how a turbo pump works.


  • Operating Principle. Most turbo pumps use several stages. Each stage has a fast rotating rotor blade and a stator blade. The pump works like a compressor that puts energy into the gas, instead of removing it out. When the gas molecules enter through the inlet, the rotor blade hits the molecules. As a result, the mechanical energy of the blades is transferred to the gas molecules, and they acquire momentum. The molecules use this momentum to enter into the gas transfer holes in the stator. The molecules collide again with the rotor surface leading them outward to the exhaust.



  • Bearings. When mounting the shaft of a turbo pump rotor through two ball bearings, you need to arrange both bearings on the fore-vacuum side due to the lubricants in the bearing. The rotor will achieve unilateral support with its large mass. In respect to rotor dynamics, hybrid-bearing support is advantageous. Hybrid bearing requires you use the concept of two bearings. An oil-lubricated ball bearing is mounted on the end of the shaft on the front side of the vacuum. The other side of the vacuum is fitted with a maintenance-free and wear-free permanent magnetic bearing that centers the rotor radially.



  • Motors/Drives. Brushless DC motors that afford rotational frequencies of up to 1,500 HZ are ideal for driving the rotors. The frequency enables the blades to achieve the required velocities to pump the gases. The drives are attached directly to the pump. You should use a power supply of 24, 48, or 72-volt direct current. You can either use an external source of power or use the pack that is integrated with the electronic unit of the pump.



  • Generating Clean Vacuum. Turbo pumps can generate a clean vacuum in the range of 10 hPa. Since they have a high compression ratio, they can keep oil from the inlet area. You can bake out those models with stainless steel housings making these pumps ideal for research and development applications. You can use turbo pumps to evacuate large vessels with rotary vane pumps as backing pumps. When it comes to turbo drag pumps, you have to use two-stage diaphragm pumps as backing pumps. However, since they have a low pumping speed, it takes them long to drain large vessels.



  • Evacuating Load Lock Chambers. Evacuating load-block chambers requires clean handling when transferring the pieces to be treated in a vacuum process. If you opt to channel in these items from atmospheric pressure, you should first pre-evacuate the chamber through a bypass line. Finally, connect the running turbo pump between the backing pump and the chamber using valves.   



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