Vacuum pump selection method and formula into 1)

in the vacuum degree of vacuum chamber from the extraction of gas molecules, the effect of reducing the gas pressure in vacuum chamber, the vacuum. From the atmosphere to the high vacuum, generally speaking, there are a large range, so far not one of the vacuum system can cover the scope. Therefore, to achieve different products, processes, work efficiency and life requirements of the target, different parts of the need to choose a different vacuum vacuum system configuration. To achieve optimal configuration, select vacuum system, should consider the following:, determine the vacuum work scope: must first check, to ensure that each process requirement of the vacuum. Because each process, so as to adapt to the range of vacuum, must study carefully, to make sure it. , determine the maximum vacuum in determining the limiting vacuum of vacuum pump on the basis of the examination system of the technical requirements, because the system determines the maximum of the vacuum system vacuum and the best work. In general, by % above, in the vacuum system and control system in the highest limit vacuum pump to reduce % than before. , types, and emission gas drainage CaiLiang check to make sure the process requirements and exhaust PaiQiXing quantity. If the pumped gas type reaction liquid pump system will be affected by pollution. Exhaust must be considered at the same time, in order to determine the appropriate time and process of exhaust gas. Volume, vacuum check to ensure that within the prescribed time required to vacuum, vacuum tube flow resistance and leakage. Meets the requirements of considering the need to keep the vacuum water output of a certain technical requirements after vacuum condition. , the formula of vacuum pump manufacturer S =. V/tLog（ P / P) Among them: for the vacuum pump (S L/s) V for vacuum chamber volume ( L） T satisfy the vacuum time ( s） Degree requirements is the initial vacuum (P ) The requirements of vacuum (P ) Argument, for example, a = = l t = second TorrP = Torr method is: S =. V/t log ( P / P) =。 x/xLog（ Seven hundred and sixty over fifty) =。 Type of L/s, of course, is just a theoretical calculation, a variable factors, such as does not consider conduit flow resistance, leakage, filter resistance to flow, smoke gas temperature is taken. In fact, the safety factor should also be taken into consideration.