Tightning torque aluminium?
Tightning torque aluminium?
(OP)
Hi
I have an aluminium detail with some helicoil holes (M6, M8, M10 and M12). The material is EN 5052 T5, which is an aluminium alloy which has Rp0,2 on 60 MPa, which isn't that much. The bolts is 8,8
What tightening torque should i use? There r tabels for 8,8 screws, but the strength of the alloy is only 60 MPa so i wonder if i should use less?
I have an aluminium detail with some helicoil holes (M6, M8, M10 and M12). The material is EN 5052 T5, which is an aluminium alloy which has Rp0,2 on 60 MPa, which isn't that much. The bolts is 8,8
What tightening torque should i use? There r tabels for 8,8 screws, but the strength of the alloy is only 60 MPa so i wonder if i should use less?





RE: Tightning torque aluminium?
Chris, CSWA
SolidWorks 13
ctopher's home
SolidWorks Legion
RE: Tightning torque aluminium?
http://www.collycomponents.se/wp-content/uploads/2...
In the first row in the table it says for M12 15.5 Nm on 1st screwing-on; but what is the rows below about? 1st screwing-off, min and 5th screwing-off, min ???
RE: Tightning torque aluminium?
http://www.dalecompany.com/pdf/UNBRAKO.pdf
Generally helicoiled holes are considered even stronger than holes tapped directly in the material.
Plenty of machine design books would offer the 1.5X diameter rule to develop full strength of the fastener in generic aluminum.
RE: Tightning torque aluminium?
RE: Tightning torque aluminium?
http://www.collycomponents.se/wp-content/uploads/2...
In the first row in the table it says for M12 15.5 Nm on 1st screwing-on; but what is the rows below about? 1st screwing-off, min and 5th screwing-off, min ??? "
I believe that table is just for inserts with deformed threads to provide a degree of self locking.
So the "screwing off" values are likely the minimum prevailing torque expected of an insert in good condition when the mating fastener is removed and installed repeatedly.
RE: Tightning torque aluminium?
RE: Tightning torque aluminium?
RE: Tightning torque aluminium?
RE: Tightning torque aluminium?
Personally I'd think torquing it to the spec of the bolt would be fine but it can't hurt to test the theory.