Bolt Length Calculation
Bolt Length Calculation
(OP)
How many threads shall be remained after tightening of bolt and nut?
Bolt length calculator which I found on the internet mentioned that 1/2 diameter of bolt should be added for a tolerance but not mentioned about the references like standards or regulations.
Please let me know if there is any standard or regulation stating above.
Thanks
Bolt length calculator which I found on the internet mentioned that 1/2 diameter of bolt should be added for a tolerance but not mentioned about the references like standards or regulations.
Please let me know if there is any standard or regulation stating above.
Thanks





RE: Bolt Length Calculation
Regards,
Cory
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RE: Bolt Length Calculation
RE: Bolt Length Calculation
RE: Bolt Length Calculation
Chris
"In this house, we obey the laws of thermodynamics." Homer Simpson
RE: Bolt Length Calculation
Rod
RE: Bolt Length Calculation
RE: Bolt Length Calculation
Rod
RE: Bolt Length Calculation
I feel better with what I have posted above. Bolt cost are small thing when compared to a joint problem. (I have worked with bolts from #10 to 2.5 inch)
Chris
"In this house, we obey the laws of thermodynamics." Homer Simpson
RE: Bolt Length Calculation
rmw
RE: Bolt Length Calculation
RE: Bolt Length Calculation
RE: Bolt Length Calculation
RE: Bolt Length Calculation
In most of the world, critical subsea flanges are almost always tightened by the use of bolt tensioners rather than torque wrenches. This enables all bolts to be tightened simultaneously with a great degree of accuracy and speed not possible through torquing.
The extended length beyond the nut of bolts (studs, actually) intended to be tensioned is the equivalent of at least 1 times the diameter for topside/shore applications. For subsea flanges, it's usually 1.5 to 2 times.
The extension is only required on the end of the stud which is to be tensioned. The typical 2-3 threads is sufficient on the other end. In most cases with pipe flanges, this means that, on one side of the flange, every other stud will have the longer extension. Then, on the other side, the configuration is repeated with the exception that the tensioners are indexed by one. Thus, 50% of the tensioners are installed on one side of the flange while the other 50% are installed on the opposite side of the flange.
It sounds a bit convoluted to the uninitiated but it's really quite simple (and darn effective!)
Ciao,
HevïGuy
www.heviitech.com
RE: Bolt Length Calculation
For hydraulic tensioner connection an extension of threads beyond the nut is usually required, but for the wrench tighten bolts and studs additional threads might lead to problems for a future maintenance work. However it is not a rule, it is just a recommendation.