Study on Design of Rotor Profile for the Twin Screw Vacuum Pump with Single Thread Tooth

9th International Conference on Compressors and their Systems

Lu, Y.^1 ; Guo, B.^1 ; Geng, M.F.^1

Xi'An Jiaotong University, Xi'an, China^1

关键词: Axial leakage;    Mass flow rate;    Rotor profiles;    Thread tooth;    Tooth profile;    Twin screw;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/90/1/012007/pdf
DOI  :  10.1088/1757-899X/90/1/012007

来源: IOP

【 摘 要 】

The trapezoidal profile is always used as part of tooth profile in the screw vacuum pump. However, interferential phenomenon occurs when using trapezoidal tooth profile. The arc is added to the trapezoidal profile to obtain the self-conjugate curve. The geometric characters of new profiles are compared with the old ones from view point of area of leakage triangle, length of contacting line, area utility coefficient, and etc. The rotor with the selfconjugate curve has characteristics of the small axial leakage area. Radial leakage from the carryover was within the same volume and would not influence the mass flow rate of the vacuum pump. High ultimate vacuum can be reached by utilizing this profile.