Sigraflex M&Y Factors
Y, Yield Factor The factor that represents the minimum load over the contact area of the gasket that is required to provide a sealed joint, with no pressure in the assembly ( i.e. seating stress).
Y, Factor Determination Determine the leak rate versus bolt load with 2 psi of nitrogen or water in the system, using increasing bolt loads to develop a load versus leak rate curve.
Y = Fastener Force ÷ Gasket Contact Area
M, Maintenance Factor The factor that provides the additional preload capability in the flange fasteners to maintain sealing pressure on the gasket after internal pressure is applied.
M, Maintenance Factor Determination Use decreasing bolt load and 300 psi internal pressure to calculate and plot M versus leak rate. Choose an M that yields an acceptable leak rate.
M = (Fastener Force - P x A internal) ÷ PxAgasket
Required Bolt Force = greater of : Y x Agasket
or
P x A internal ÷ M x P x (2b x 3.14 G)
Where b = effective gasket width and G = gasket OD
M & Y Factors for Sigraflex Materials
Homogeneous grades and solid foil core laminates (i.e, B-Lam, Bssc, BMY. etc.)
Y = 900, M = 2
Tang core and screen core laminates (i.e. BTCSS, BSC)
Y= 2500, M = 2
This information is based on SGL's current knowledge and is intended to provide general notes on our products and their uses. It should not therefore be construed as guaranteeing specific properties of the products described or their suitability for a particular application. Any existing industrial property rights must be observed. The quality of our products is guaranteed under SGL General Conditions of sale |