I'm analyzing large bore sch. 10s pipe for full vacuum internal pressure. I'm wondering whether Caesar has the capability to determine if stiffener rings are required? If a manual calculation is required what's the reference? Also whether it's a two part calc, one part on whether the stiffeners are required and part two, the spacing of the stiffeners on the pipe.

No. Do not run CAESAR II with a negative pressure. In fact, when Version 5.10 is released, CAESAR II will throw an error if you enter a negative pressure.

"I'm analyzing large bore sch. 10s pipe for full vacuum internal pressure. I'm wondering whether Caesar has the capability to determine if stiffener rings are required?"


No are you kidding me! This is a beam element program.... you should learn what implications that has!

ASME B Division 1 UG 28 to UG 30. Check your design code for more details. ASME B31.3 has info in 304.1.3. Refers to ASME.

If the calc gives no rings you may be better of adding them for manufacturing and erection reasons. 10s large bore (duct size)can be very difficult to handle without rings. If your company is paying for fabrication and erection you can save stack of money by designing rings correctly. If you design them wrong you will not be popular.

How to calculate? Slide rule, pen, paper and a bit of time