on what size hydraulic tensioning of bolts should be applied?

[mike mufdi]

What is the criteria for applying hydraulic bolt tension? In shell DEP 31.38.01.31-Gen article 3.12.4 specify hydraulic tension for bolts larger or equal to 1.5" , while in appendix 6 of same document puts hydraulic tension at 2" and above.
On a second note the tables in appendix 6 does not specify any values for bolt tensioning, where can we specify these values .
Thanks

 

[MJCronin]

"Mike"

Could you share your copy of Shell DEP 31.38.01.31 with us ???

PDF format is preferred ...

What other Shell DEP standards can you make available ??

Do you work for Shell ?????

MJCronin
Sr. Process Engineer

 

[mike mufdi]

Hi MJCronin,

The Shell DEP I use is company owned and I can not share it here, You can contact your company to provide the same. No i do not work for shell and Hope you have an answer to my question.

 

[LittleInch]

Mike,

I'm not aware of any specific requirement for hydraulic bolt tensioning in general though you clearly have a company specific document giving you some guidance. Those are pretty big bolts so I guess there is no real way to get accurate force values per bolt otherwise.

In my experience hydraulic tensioners tend to be an offshore thing / subsea where it is difficult to get accurate tensioning done any other way, but in some circumstances might be undertaken for very large bolts or sensitive ones onshore.

But as we don't all have copies or up to date copies of the Shell DEPs, we can't really comment on the specifics of your query.

Criteria for me is can you achieve reliable bolt tension any other way.
Is there room for the tensioning equipment?
what is the cost / benefit calculation / assessment?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[BEMPE16524]

i couldn't find any standard on hydraulic bolt tensioning but here is a good info on the calculation: Link
also there is a discussion in this forum: Link

Also, here is the standard from Petronas (Bolted Flange Joint Assembly PTS 12.00.06):

MTW = manual torque wrench
HTW = hydraulic torque wrench
HBT = hydraulic bolt tensioning

R.Efendy

 

[mike mufdi]

Thanks for your replies,

@littleinch bolt tensioning is common on all oil and gas specially when bold dia goes more than 1.5inch.

@BEMPE16524 , dear R.Efendy , the table is similar to what Shell DEP says in 3.4.12

and here is the conflict,the table you shared also indicates HBT to be done for ratings 1500# and above when bolt size is 1.5" and above, but appendix 6 puts the HBT for these ratings still for bolts 2" and above:

so shall we use HBT by following the 1.5" or 2" limit ?

 

[TGS4]

Specification conflicts ought to be resolved with the author (company) of the specification. IN fact, at the start of the specification, there is usually a conflict resolution mechanism. Follow that.

 

[BEMPE16524]

i guess it is up to the client to decide.
sometimes it is purely depends on historical experience due to cases such as accident and some updates are not tally with the reference.
as you can see from the ASME table, the suggestion for HBT is higher (2") and in DEP and Petronas PTS, the requirement is lower and i'm pretty sure they have studied the reason.

R.Efendy