Hybrid_From_Hell Posted May 1, 2012 Share Posted May 1, 2012 Hi all I am familiar with 8.8 and 12.9 "grades"etc in bolts But can someone translate what a grade v bolt is - same I think as a grade 8 bolt ? Can some lond soul tell me - or web link to translate into the 8.8 10.9 12.9 type grading system please ? Nige Quote Link to comment Share on other sites More sharing options...
fozsug Posted May 1, 2012 Share Posted May 1, 2012 Are you sure you dont mean 'Y' never heard or seen 'V' http://www.engineersedge.com/hex_bolt_identification.htm Quote Link to comment Share on other sites More sharing options...
Maverik Posted May 2, 2012 Share Posted May 2, 2012 Hey up... here's a few more to look over... http://www.dot.state.il.us/materials/fasteneridentificationguide.pdf Quote Link to comment Share on other sites More sharing options...
mmgemini Posted May 2, 2012 Share Posted May 2, 2012 Ah you found "proper" bolts...LOL Now you've heard me call 8.8 bolts as soft as a carrot. IMO they are. Now from memory, I wouldn't even know where to look for my Britool book now.. Standard grade bolts were R grade. S was better. I think, only think if memory is correct the Allen bolts were V grade... You can't translate those figures across because it relates to Imperial UNF and UNC. As I say, all from memory. Quote Link to comment Share on other sites More sharing options...
elbekko Posted May 2, 2012 Share Posted May 2, 2012 You can't translate those figures across because it relates to Imperial UNF and UNC. Of course you can, just match the bolt properties (tensile strength etc) between the two systems, and find what's closest. Quote Link to comment Share on other sites More sharing options...
mmgemini Posted May 2, 2012 Share Posted May 2, 2012 Of course you can, just match the bolt properties (tensile strength etc) between the two systems, and find what's closest. How please. V rating is the tensile strength... How does that compare with what is used now ? Well my copy of Fowler pre dates the letter numbering.....It's a 1946 copy. Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 2, 2012 Author Share Posted May 2, 2012 I have this sort of tbinmg for metric This gives me data for say the 8.8 vs 12.9 metric stuff, but I am trying to work out where it the numeric scale shall we say does a V Grade UNC/F Bolt "Fit" ? Having trouble too ! Nige Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 2, 2012 Author Share Posted May 2, 2012 yabbadaabado...... From an Email to moi Grade V Grade (10.9) or R Grade (5.6) So, a V UNF/C=10.9 +/- Nge Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted May 2, 2012 Share Posted May 2, 2012 This DOESN'T give you your answer as it stops at the letter T grade but is sort of interesting http://www.britishfasteners.com/BRITISH_SERIES_BOLT_HEADMARKINGS.pdf Quote Link to comment Share on other sites More sharing options...
elbekko Posted May 2, 2012 Share Posted May 2, 2012 How please. V rating is the tensile strength... How does that compare with what is used now ? Well my copy of Fowler pre dates the letter numbering.....It's a 1946 copy. A quick Google tells me this: http://autos.groups.yahoo.com/group/triumph_herald/message/7453?var=1 V grade (70-75T in), [..] 12.7 grade (76.2T in) Surely there should be a nice table somewhere outlining the properties of a V grade bolt, else it wouldn't be much of a standard. Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted May 2, 2012 Share Posted May 2, 2012 Are you perchance doing your manifolds on your V8? http://www.landroverclubvi.com/uploads/2/3/9/8/2398536/v8_manifold_bolt_re-use_sec.pdf Quote Link to comment Share on other sites More sharing options...
mmgemini Posted May 2, 2012 Share Posted May 2, 2012 Been shopping for nuts and bolts today. Teeside Industrial Fasteners... He got his old books out. Seems I'm wrong...Nothing unusual there. R grade is for BSF and Whitworth. S grade is for UNF and UNC... We couldn't find any reference to a V grade. There doesen't seem to be any cross reference. I'm mistyfied because I'm sure I've heard of V grade. Have you a copy of Fowlers Machinist Handbook from about the early 1980's. You might find something in there. Quote Link to comment Share on other sites More sharing options...
integerspin Posted May 3, 2012 Share Posted May 3, 2012 You will find V and X on old flywheel bolts. I thought they were makers marks. Quote Link to comment Share on other sites More sharing options...
zoltan Posted May 3, 2012 Share Posted May 3, 2012 Macreadys Orange book can translate the S, T, V etc IIRC it is relates to the tensile properties given by different heat treatments on steels I'll find the book at work and post some details Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted May 3, 2012 Author Share Posted May 3, 2012 Yippee ! Nige Quote Link to comment Share on other sites More sharing options...
Daan Posted May 3, 2012 Share Posted May 3, 2012 If strength is a concern, just use a NAS bolt. Daan Quote Link to comment Share on other sites More sharing options...
zoltan Posted May 3, 2012 Share Posted May 3, 2012 I'll post up a picture of the page tonight, it is part of BS 970: Part 1: 1983 Tensile ranges the useful bits: T is 850-1000 N/mm2 55-65 tons/sq in U is 925-1075 N/mm2 60-70 tons/ sq in V is 1000-1150 N/mm2 65-75 tons/sq in runs from P through to Z. I'll post the whole thing up tonight for reference but that should help for now Quote Link to comment Share on other sites More sharing options...
mmgemini Posted May 3, 2012 Share Posted May 3, 2012 Great, thank's. I'll be printine that off for future reference. Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted May 3, 2012 Share Posted May 3, 2012 Was having a bit of a google for that Macreadys orange book (it's £25 btw) and came across this interesting (to me anyway) bit of info .... 'The EN numbers came about because at the start of WWII there were 100's of different grades by different manufacturers. They got all the relevant steelworks representatives to attend a meeting at a hotel and told them they had to come out with a standard whilst the war was on. They locked them in the room and told they couldn't leave until they had reached an agreement. This is how the EN series came about. EN stands for Emergency Number. This BTW is true and not an urban legend. John S.' No idea if it's true, but interesting none the less Quote Link to comment Share on other sites More sharing options...
zoltan Posted May 3, 2012 Share Posted May 3, 2012 It used to be free if you were an account customer! Very useful book, ours is more of a dirty brown colour now. Quote Link to comment Share on other sites More sharing options...
CwazyWabbit Posted May 3, 2012 Share Posted May 3, 2012 It used to be free if you were an account customer! Very useful book, ours is more of a dirty brown colour now. I imagine they make a tad more than £25 out of you as an account customer Looks to be an interesting/useful book from the description Quote Link to comment Share on other sites More sharing options...
zoltan Posted May 3, 2012 Share Posted May 3, 2012 Yes it is well worth the £25 IMHO if you are using lots of different engineering steels. It has a good section on selecting steels too. In the back is an index of relative machinability for steels with EN1A as a number 1. Quote Link to comment Share on other sites More sharing options...
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