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View Full Version : Pipe threads revisited



SGW
08-17-2001, 07:41 PM
I'd check www.mscdirect.com (http://www.mscdirect.com) or www.travers.com (http://www.travers.com)

Col Mckee
02-13-2006, 09:24 PM
After taking a crash course on NPTF threads I think I understand. Where do I find a die to cut NPTF external threads to mate with NPSF internal threads? The NPSF tap is easy, but the die is a whole 'nother ballgame. Nobody I've talked to knows what I'm talking about. Thanks, John

chief
02-13-2006, 09:45 PM
Start with ebay, Mcmaster-Carr etc.

Col Mckee
02-14-2006, 09:38 PM
Perhaps a better way to ask my question: Is a NPTF external thread different from a NPT external thread, and if so, how? Dies are readily available for NPT external threads but no one (including MM-C) recognizes NPTF as a valid DIE description. Thanks, John.

HWooldridge
02-14-2006, 11:13 PM
Yes, NPTF is different from NPT. It is the national standard for Dryseal pipe threads, i.e., the type of threads intended for use to seal against pressure without using sealing compounds. Used in refrigeration and other types of systems where a clean tight union is desired.

The above paraphrased from Machinery's Handbook, 22nd ed.

Scatterplot
03-01-2006, 09:51 PM
Would something like this work-
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=38438
Granted I don't think they're NPTF, but there's more-
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=30027

If you're going cheapo, HF has a lot of this kind of thing for different prices/quantity, but like someone else said McMaster, Enco, MSC, probly eBay have what you need.