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SA-193 B8 CL2 bolts torque for B16.5 Ring Joint #2500 and #600 application

FPPE

Mechanical
Mar 4, 2022
162
Hi,

Could you please provide torque chart for bolts in SA-193 B8 CL2 for ring joint B16.5 flanges application, with rating 2500 and 600?

Thanks
 
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Torque is dependent on a lot of things, which yo haven't specified — for example, not only flange size, but also flange material, gasket material, anti-seize, etc. One crucial aspect is knowing/understanding the nut factor. In the end, the gasket stress is what matters, and that's achieved by bolt load. Getting load by torque heavily depends on (understanding) friction, hence the nut factor. Tooling is another factor (Im foreseeing future comments saying this requires bolt tensioning rather than hydraulic tooling).

In general, this question is too open to be answered, but is also asking if someone else wants to do your homework, for a subject matter you might not know enough about.

Start reading PCC-1, and take this excellent free course by HexTech on PCC-1. If you then still have further questions, Id be happy to hep wherever I can.

Huub
- You never get what you expect, you only get what you inspect.
 
XL83NL, thank you for your reply and I apologize if my question was superficial.
I meant to ask if there were directly tables for these combinations, leaving out the flange material and obviously providing different options for nut factor and tooling.
I will try to calculate the torque anyway by setting up the calculation with the App. K or with the App. O joint approach of PCC-1.
 
Appendix O has some default torque values, but not for your situation (RTJ).

Whats the size and flange material? What K-factor do you expect?

A bit off-topic here, hopefully someone more knowledgeable on BFJ's and PCC-1 isreading along; how does one determine the appropriate Appendix O factor for RTJ gaskets?
Especially O-4.1 Sg[sub]T[/sub], Sg[sub]max[/sub], Sg[sub]min-S[/sub] and Sg[sub]min-O[/sub]. Im assuming φg = 0.7. EN 1355 doesn't have data on RTJ's

Huub
- You never get what you expect, you only get what you inspect.
 
Use hydraulic stud tensioner: elongation, not torque.

Regards
 
XL83NL,

K-factor should be about 0.20.
Flange material Monel 400 SB-564 N04400 - 1/2", 4", 6" and 8".
Thanks for the answer.

r6155, thanks for the advice.
 
Dear FPPE
I do not have now b16.5, but have you verified if bolts b8 cl2 are classified as high or intermediate strength?
If they are classified as intermediate, you shall perform a detailed calculation and from that you can easily obtain a bolt load to be applied. Total load is the wm1 load multiplied by phydro/pdesign. In any case, increase the bolt load up to you reach as a minimum 40% cold yield stress of the bolt. If they are classified as high strength (but I doubt) I would set as target bolt stress around 300 mpa, maybe verifying that bolt all stress*phydro/pressing is lower than 300. Just ensure do not exceed 70% of bolt cold yield stress.
Note that pcc app o won’t help you for rtj gasket.
Note that for big size bolts, bolts sa 453 660 may be more appropriate.
Note also that hydraulic tensioner may not be appropriate, especially for small size bolt.
 
At the end of the day, it is a leak tight connection one desires.
The PCC-1 App O gives the most comprehensive flange assembly tightness solution.
Some expert will tell you to use Dennis Moss equations. The problem with Dennis Moss is that it doesn't consider the full capacity of the joint assembly that can sustain the stress. It doesn't consider the max target load, flange rigidity. It simply provides what is sufficient for pressure and minimum gasket seating.
Often bolt torque designed to Dennis Moss leaks.
SA 193 B8M CL 2 falls under High Alloy Steel (UHA) of Sec VIII Div 1. Allowable stress values are contained in Sec II Part D subpart 1.
You will need to obtain few data input from the gasket manufacturer to work with Appendix O of PCC-1. You will also need to look at Appendix J and K.
 
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