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nuts & bolts
davey - 5/12/05 at 03:39 PM

ive got a load of stainless M8 nuts & bolts
i understand i need a specific grade for sva if so what is it?
these have A2-70 stamped on them mean anything to anybody
cheers


jos - 5/12/05 at 03:44 PM

For any load bearing or structural/safety areas they need to have 8.8 moulded into the head of the bolt.

ie seat belts, suspension pick ups etc

[Edited on 5/12/05 by jos]


iank - 5/12/05 at 03:48 PM

A2-70 is a 304 stainless steel screw with a 700 N/mm2 tensile strength

Not good enough for suspension (or rollbar IMO) but good enough for general stuff.

http://home.jtan.com/~joe/KIAT/kiat_2.htm has some useful information.


jambojeef - 5/12/05 at 06:45 PM

Yeah agree with iank,

This table shows the different properties of stainless and high tensile steels.

You would think looking at their absolute values that either would be well within acceptable safety margins but bearing in mind that most suspension bolts arent mounted purely in tension but mostly in double shear it pays to pick a 8.8 HT bolt if using metric or the equivalent imperial rating which is "S" - like my 1/2" UNF bolts for my top bones.

Geoff Rescued attachment Material Tensile Strength.jpg
Rescued attachment Material Tensile Strength.jpg


davey - 6/12/05 at 08:39 AM

cheers
all