Female thread max torque 1

[ardor]

Hello,
I'm looking for a way to determine the max torque i can apply on a female thread.
I'm working with 3 different aluminium alloys(6063TS, 61T5, 6061T6) at different screw thread (M2, M2.5, M3....)


Please excuse me if i missed any crucial information, and thanks a lot for helping

 

[drawoh]

ardor,

There is lots of stuff about this in the Machinery's Handbook. If your over-torque this, the weakest component will fail. This is not necessarily the female thread.

Aluminium is not good material to tap holes into. If the holes must be strong, or they are to be used repeatedly, or you are just worried about them, it is common practice to use helical thread inserts.

--
JHG

 

[handleman]

1. Get a quality male thread from a strong material
2. Get a torque wrench
3. Break stuff

 

[Tmoose]

- You provided no info about screw material, joint design, components being screwed together, or how much clamping force you need.

For the rather open ended question " what is maximum torquage?" The Unbrako engineering guide has some good info , starting on page 63 or so.

http://www.unbrako.com/images/downloads/engguide.pdf

A couple of diameters of engagement in some pretty wimpy materials exceeds the "strength" of SHCS.
Note for exmple Depending on screw head style, and component material, screw head embedment may set the limit for maximum torque.
I try to keep required clamp force foremost in my mind. See the first bullet.

 

[hydtools]

vishal.dixit, your link is to a guide on how to use the handbook. That site does have a link to the 30th edition of the handbook.

Ted

 

[Screwman1]

If you are seating the screws against the bearing surface, remember that about 50% of the applied torque get eaten up in underhead friction and never makes it to the threads.