THREAD FIT 1

[DUNCP]

I have been asked to quote for 5/8" and 3/4" studbolts C/W 2 nuts - Hot Dip Galvanised finished.

I have offered standard studs with nuts tapped oversize to accommodate galvanising.

Customer has now added the following to their specification:

Studs shall be to tolerance class 8G before galvanising
Nuts may be re-tapped after galvanising to 5H.

I can't equate above tolerances to imperial threads, can someone advise if these tolerances are applicable to imperial diameters?

 

[desertfox]

Hi
The class designation in your post are for metric threads, imperial threads are A and B
see link below:-

http://en.wikipedia.org/wiki/Unified_Thread_Standard

 

[Screwman1]

Those tolerance cannot be applied to inch dimensioned threads, they are only applicable to metric threads. Ask your customer to give you the appropriate ANSI spec tolerance. I hate it when this type of mixed systems spec interaction happens- it drives my up the wall, it shows a total lack of concentration on the part of the person who puts that sort of stuff on the specification. Sorry-didn't mean to rant....

 

[KENAT]

I swear I answered this already.

Slight error in desertfox post. A & B designate external (screw) or internal (nut) threads. The 'numbers' given in the 'tolerance class' section of the link they give explains the class.

Posting guidelines faq731-376

http://eng-tips.com/market.cfm?

(probably not aimed specifically at you)
What is Engineering anyway: faq1088-1484​

 

[kingnero]

I wouldn't recommend retapping after galvanising, but then again, I don't have any experience doing so.

better quoting them for a larger tolerance.

 

[DAVIDSTECKER]

I believe that a Class 1 fit is what you are looking for.