TylerM
Mechanical
- Feb 16, 2017
- 32
During a recertification of a saddle support calculation for use in a lethal system the manufacturer identified the contact angle of the saddle supports for an ASME Section VIII Div 1 horizontal vessel was 120°. The contact area included the ½” wear plate that did not extend beyond R/10 inches above the horn of the saddle in formulas S2 for the thickness ts. The calculated contact angle at the horn of the saddle supports makes with the vessel is 116°.
With the wear plate only extending 1” past the horns of the saddle supports the manufacturer include the ½” wear plate value with the 3/16” shell thickness allowing the vessel to pass during finite element analysis, without the wear plate the vessel fails.
Am I interpreting correctly the “Pressure Vessel Handbook” by Eugene Megyesy that the stresses will be concentrated at the top of the horns of the saddle vice the added protection of the wear plate and use in determining the correct value for the 120° contact angle for my calculations?
With the wear plate only extending 1” past the horns of the saddle supports the manufacturer include the ½” wear plate value with the 3/16” shell thickness allowing the vessel to pass during finite element analysis, without the wear plate the vessel fails.
Am I interpreting correctly the “Pressure Vessel Handbook” by Eugene Megyesy that the stresses will be concentrated at the top of the horns of the saddle vice the added protection of the wear plate and use in determining the correct value for the 120° contact angle for my calculations?