API Threads

The only thing that perhaps makes them special is that the thread was probably produced and extensively in use before a standard was defined and written, as is the case with many thread forms, save for the metric forms. This reverse-engineering practice ensured interchangeability with the threads already in use. Now this is just my opinion and not based on documented facts. Compared to the American pipe thread, the A.P.I. form does have different factors for crest and root truncation. There are minute differences between the standard American pipe thread, the Dryseal pipe thread, and American Petroleum Institute pipe thread. The difference is mainly the amount of crest and root truncaion, which affects the finished profile height. Dryseal threads have closer tolerances for all parts of the flank, crest, and root with a varying formula for truncation depending on the pitch than do the American pipe threads, and through this tolerance and profile management are guaranteed to make a full metal-to-metal crush when tightened, eliminating the need for sealant. Ing. Robert Forbus

For more info go to:

www.api.org/certifications/monogram/documents/licensing-forms.cfm -

or to:

thread_lab@hemcogages.com

Good luck

HFE

Dear sir: Please inform your address, quantity ans size you need. We are a thread gauge supplier. henryzhang1@hotmail.com

HARDWICKE3@AOL.COM OUR THREADS ARE 2.375 API REGULAR WE NEED THREAD GUAGES THANK YOU NICHOLAS @ ALTOONA HYDRAULICS

Can you supply the specs on API 2.875" 8rd EUE & API 2.375" 8rd EUE. Thanks! Kirk

mailto:sales@pmclonestar.com this is where you can get and buy api gages and information. I have used their gages and services and they are top notch.

"Any idea why API threads are used or what makes them so special?"

The reason for API anything is standardization of equipment for oil & gas.

probably your best source of information would be www.api.org

Chris

Does anybody know where I could get the official drawings for the API threads?

Thank You.

You can get the specifications at www.global.ihs.com . They would be API 5B, API 11B or API 7-2 depending on the thread. There are others but these are the most common. You can get the gauges at www.api-gauges.com or sales@api-gauges.com

Jerry

sales@api-gauges.com