Hello,

I am about to start my work on refrigeration piping for the first time and trying to use B31.5 in CAESAR-II version 5.3 When I select code from the drop down menu, it shows allowable stress value only for SH1 even though there are 3 temperatures defined in stress model.
I am curious to know if I have to put in other values manually. I would appreciate if someone could put light on it.
Thank you.

-Vinay

That is surprising behavior. Please send your model in to Tech Support so we can look at it.

Dear Richard,

Digging back old thread. any update for the matter above? i also having the same problem where only SH1 value was shown. i define 2 temperatures in stress model. do i have to put in manually for the other SH?

FYI I am using Caesar II version 5.30.02

Did you send the model in? I'm not in Support, so I wouldn't be involved unless they need my help.

Owh ok i thought you are the one checking Vinay's model. not yet sending to technical support team. currently i key in manually the SH values.

Dear all,

I need some help. I am dealing with design temperature of -165 degC. I want to ask regarding the Sy value at the Piping Input Window. In Caesar II Online Documentation page, it says:

"B31.5. Used to satisfy the requirements of Paragraph 523.2.2.f.4. This paragraph addresses ferrous materials in piping systems between -20 degF and -150 degF. The value entered here should be the quantity (40% of the allowable) as detailed in the Code. When Sy is defined, the OPE case will be considered a "stress case". The allowable reported in the output report will be the value entered here. The computed operating stress will include all longitudinal components, and ignore torsion."

In ASME B31.3 para 523.2.2 (4) says;

"Impact tests are not required for ferrous materials used in fabricating a piping system for metal temperatures between -50 degF (-46 degC) and -150 degF (-101 degC) provided the maximum circumferential or longitudinal tensile stress resulting from coincident pressure, thermal contraction, or bending between supports does not exceed 40% of the allowable stress for the materials as given in Table 502.3.1."

For material ASTM A213 TP304L, the minimum temperature is -425 degF (-254 degC). Therefore since my design temperature is lower than -150 degF (-101 degC), I need to key in manually the Sy value which is 40% of allowable and make it as allowable for my calculation. Is it correct?

Please comment. Thanks.

I try to refer to 523.2.2(f) intentions "The following materials are exempted from the requirements for impact testing [...]"

304L case is covered by 523.2.2(f)(1)

(1) Impact tests are not required for aluminum; Types 304 or CF8, 304L or CF3, 316 or CF8M, and 321 austenitic stainless steel; copper; red brass; copper-nickel alloys; and nickel-copper alloys.

You mixed with 523.2.2(f)(4) Impact tests are not required for ferrous materials used in fabricating a piping system for metal temperatures colder than −20°F (−29°C) down to −150°F (−101°C) provided the maximum circumferential or longitudinal tensile stress resulting from coincident pressure, thermal contraction, or bending between supports does not exceed 35% of the allowable stress for the materials as given in Table 502.3.1. See para. 502.3.2 and sections 519 and 520.

(I quote B31.5- 2006. I haven't a newer one).

dear Mariog,

thanks for your reply. missed out the point 1 as you highlighted. this mean i don't have to enter the Sy value right?

I think 523.2.2(f)(4) should be improved and B31.5 committee would answer to a basic question: is austenitic stainless steel a ferrous material or a non-ferrous material?

Under B31.5 common sense interpretation you don't need to consider impact test for 304L hence you don't need to consider that stress level check as a control of impact test requirements.