Compress and UG-45(b)(1)

[plantguyjj]

Tom,

When performing UG-45(b)(1), why does the program sometimes use the Appendix 1-1 formula for tr and other times the UG-27(c)(1) formula is applied?

 

[Kashanulhasan]

It depends if you are going for a fabricated nozzle (made by plate).

 

[doct9960]

plantguyjj,

The UG-27(c)(1) formula is based on the cylindrical shell inside radius. The Appendix 1-1(a)(1) formula is based on the outside radius.

You may have modeled some cylinders based on the OD and some based on the ID. Compress will use the UG-27(c)(1) formula for nozzles located in the "ID" cylinder and Appendix 1-1(a)(1) formula for nozzles located in the "OD" cylinder.