Thread Form Decode (Oil and Gas stuff)

[Pud]

I need to draw up a threaded protection cap for one of our customers.
Being oil industry stuff, they all seem to use "home made" thread forms ( I think)

The thread is designated:

6.11/16" - 5NA - 2G (STD)
Major Dia 6.688/6.788

My question is: what is the pitch?

Sorry to be thick - I usually just get a part off them and measure it, but they have none at present and I want to get on with the cap design,
Cheers

Harry



www.tynevalleyplastics.co.uk

It's ok to soar like an eagle, but weasels don't get sucked into jet engines.

 

[waross]

Is this drill pipe thread? Try this link;

http://www.bournedrill.com.au/a-tool joint.htm

I found it with this search;

http://www.google.ca/search?hl=en&s...=HPIuZ-WsU2yFVM:;YoCQt9jFcVZapM;http%3A%2F%2F

http://www.bournedrill.com.au%2FA-T...nedrill.com.au%2Fa-tool%2520joint.htm;724;325

This may help find the profile.

Bill
--------------------
"Why not the best?"
Jimmy Carter

 

[Pud]

Hi Bill,

No. it's not a drill pipe thread - the part description is:

Integral Pupjoint - 15K CWP

Is this a "closed" forum? I can upload the drg if it is...

Cheers

Harry



www.tynevalleyplastics.co.uk

It's ok to soar like an eagle, but weasels don't get sucked into jet engines.

 

[ivymike]

not a close forum

 

[btrueblood]

Pud,

That appears to be a thread callout per the U.S. (inch) ACME thread standard. "Pitch" is 5 threads/inch, in National Acme thread form, with 2G thread tolerances.

Some more info. here

http://www.diracdelta.co.uk/science/source/a/c/acme thread/source.html

you can get a copy of the standard, if you need one, from

http://global.ihs.com/doc_detail.cf...=901231&input_doc_number=b1.5&input_doc_title

Machinery's Handbook should list all the info. that a competent machinist would need to cut the thread.

 

[Pud]

Cheers guys - I get it now. It was the 5NA - especially the NA bit I am unfamiliar with. (Although I do know of Acme threads!!)

LPSs all round!!

Harry

www.tynevalleyplastics.co.uk

It's ok to soar like an eagle, but weasels don't get sucked into jet engines.

 

[btrueblood]

Glad to help, Harry - I finally get a chance to pay back some of your priceless advice from over the years.

 

[KENAT]

Should be interchangeable with the old BS ACME threads from what I recall Pud.

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