M. Jeráb, T. Gronych, L. Peksa, F. Stanek, Z. Krajícek, D. Pražák, M. Vicar, J. Tesar
MULTI-OPENING ORIFICE - A TOOL FOR PRIMARY METROLOGY OF VACUUM AND SMALL GAS THROUGHPUTS
Multi-opening orifice is a device for gas flow and related vacuum quantities primary measurement. It keeps molecular flow regime and thus possibility to calculate the conductance very accurately from geometrical dimensions up to relatively high pressure. Moreover, the value of the total conductance could be sufficiently high to achieve reasonable parameters of the used vacuum system. Suitable shape of a multi-opening orifice duct and principles of multiopening orifice design are discussed. An example of the multi-opening orifice manufactured with grinding is given. Limits and requirements for further development are drafted.