Standard Practice for Determining the Maintenance Factor (m) and Yield Factor (y) Loading Constants Applicable to Gasket Materials and Designs

Importancia y uso:

4.1 The gasket factors are a function of leak rate; therefore, this practice generates curves. Constants for use in the ASME Boiler and Pressure Vessel Code, Section VIII, Appendix 2 code calculations are selected from these data. Specific m and y values can be selected based on a maximum desired leak rate or derived from these data as described in this procedure. This practice addresses the influence of leak rate and gasket thickness on a gasket’s ability to provide a seal initially and in operation. This practice is performed at room temperature; therefore, this practice does not account for all conditions, such as high temperature or thermal cycling or both, that bolted flange connections may be subject to in field application.

4.2 This practice determines two general characteristics that are specific to the ASME design criteria. Caution should be exercised when comparing yield and maintenance factors between gasket materials, and it is recommended that the m and y curves be compared. Selecting a gasket material for use in an application should not be based exclusively on these two general characteristics. Gasket material selection for a given application should consider additional information not described in this practice, which includes, but is not limited to, chemical resistance, thermal resistance, creep relaxation, compressibility, and accommodation of thermal cycling.

4.3 This practice builds upon work conducted in the Fluid Sealing Association (FSA G 605:11). The associated round robin data is provided for reference in Tables 1-4.

(A) BDL = below detection limit. (A) BDL = below detection limit.

Subcomité:

F03.40

Volúmen:

09.02

Número ICS:

21.140 (Seals, glands)

Palabras clave:

gasket designs; gasket materials; loading constants; m; maintenance factor; y; yield factor;