Calculating Fuel Fitting Torque

[mrfailure]

How do I calculate the amount of applied torque required for a fuel fitting tee from a truck diesel engine? The tee is made from 316 SS, with couplings made from carbon steel on the two branches at the top of the tee, while the outlet has a flanged 316 coupling that screws into a valve, with all fittings M10 size. Is there an established methodology I can use to calculate what the torque should be?

 

[Lou Scannon]

You best bet is to determine either the manufacturer of the fittings or the applicable industry standard they are manufactured to meet, and consult the corresponding specifications.

"Schiefgehen will, was schiefgehen kann" - das Murphygesetz

 

[franzh]

Hemi is right, especially if you are considering the failure modus of the component (as your handle implies). Consider that if an M10 bolt of the same length as your fastener has X-value torque, a hollow bolt fastener of the same size would have a drastically different torque value. If the crush washer seals are made from fibre, copper, or composite plastic, they too would alter the torque value.

There are a lot of variables to consider.

Franz

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