SAE-32 Straight Thread 1

[Eyke]

Good day:

I have a vendor drawing that calls out a 2-1/2-14 UNF SAE-32 Straight Thread O-Ring port. There is a part identified for this port. I inquired the company and was replied with a terse, "That part is obsolete."

What are SAE threads and how do they differ from ANSI threads?

TIA,
Eyke

 

[SnowCrash]

Sounds something like a dry seal port. This is similar to a NPT thread, but is custom designed for sealing without a taper. I have seen similar ports used with a sealing washer in aerospace applications.
There is a reference in my old Marks Mech Handbook which calls out a 14TPI form. Look up 'Amer Std Dryseal Pipe'.

Crashj 'another porthole' Johnson

 

[Eyke]

Could be. There is an o-ring that is part of the plug.

I looked in my Machinery's Handbook #25 under dry seal threads. 2-1/2-14 is not a standard thread, tho they do call out 14 tpi. I'm not sure if close is good enough. It depends on what the customer is installing in this port.

Thanks for the info.

Cheers!
Eyke

 

[Hush]

Are you sure its not 2-1/2-12UNF SAE-32? This is a standard straight thread tube fitting boss. The threads are 2-1/2-12UNF and SAE 32 is the tube size (2" Nom OD). O-ring size should be SAE 932 (2.337 ID 0.118 CS). Get a hold of a copy of MS33649 or contact an o-ring distributor for dimensions.

 

[Eyke]

Hush:

Yeah, 2-1/2-12. I'll get a copy of the MS spec. Thank you for the info, that clears things up nicely.

Cheers!
Eyke