I've just recived some 7/16th unf bolts ordered online for my seatbelts, described as grade S supplied marked L with 3 lines equaly spaced. I belive mr sva wont like these. does anyone have a table of bolt strength using letters for imperial bolts
Go down the srappy.. I got mine out the front of a Ford Ka. Stamped correctly and correct 7/16th thread.
i need 2.5 inch long bolts to get my belts up above the seat line not sure i'll get them from a scrappy, and i bought these specificaly for the S marking just need to confirm L is lower strength than S before i kick off
quote:
Bolts used in structural areas should be of grade 8.8 or better. Such bolts will be marked 8.8 or 12.9 on the hexagonal head, however, cap-head bolts or 7/16" ( 11mm ) UNF seat belt anchorage bolts (with an anodised finish) not marked in this way may normally be considered to be of equivalent strength. Bolts should be M8 or larger.
Are you sure thats grade S and not grade 5? The 3 equally spaced lines denote grade 5 which is equivalent to 8.8. The L is probably the manufacturers
mark.
This chart shows grade 5 and 8.8 and their specifications.
Silly thing is racing spec harnesses use 8mm 12.9 bolts. A 7/16" bolt is 11mm so unless it's made from chocolate it'll be strong enough even if less than 8.8 grade....
it'll be equivalent strength. another one of those rules people think it MUST be 7/16 UNF, and it doesn't have to be
quote:
Originally posted by matt_claydon
quote:
Bolts used in structural areas should be of grade 8.8 or better. Such bolts will be marked 8.8 or 12.9 on the hexagonal head, however, cap-head bolts or 7/16" ( 11mm ) UNF seat belt anchorage bolts (with an anodised finish) not marked in this way may normally be considered to be of equivalent strength. Bolts should be M8 or larger.
Who wrote this? Am I right in thinking this is the SVA or IVA requirement. AFAIK anodising is a surface treatment that is applied
exclusively to aluminium.
Yes, presumably they're getting confused between anodizing and electroplating. Anodizing is increasing the thickness of the oxide layer (and sometimes staining it) to improve resistance to rust. Obviously it is only a good idea for some metals- increasing the oxide layer on the outside of a steel workpiece would be a bad thing!!! IIRC it's done on metals like Ali, titanium, zinc, magnesium, stuff like that....