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Leaking Stainless Steel NPT Threads

Leaking Stainless Steel NPT Threads

Leaking Stainless Steel NPT Threads

(OP)
Can anyone suggest a good pipe sealant to use to seal stainless steel NPT threads in higher temperature service (over 250C)?  Currently use Silver Goop with poor results.  Previously used Masters Metallic but it has been banned from our company due to lead.

RE: Leaking Stainless Steel NPT Threads

(OP)
The pipes contain hydrocarbons and the pressure is up to 600# flange rating.  I am hoping for someone who has had some good experience with a particular sealant since the sales literature always promises great results.

RE: Leaking Stainless Steel NPT Threads

I suggest to make a seal-weld to the threaded joints.

RE: Leaking Stainless Steel NPT Threads

Here is an add on seal (TruSeal) we used quite extensively in a pilot plant that had all threaded pipe joints in lieu of welded fittings in a futile effort to save time and money.

http://www.millerfluidpower.com/pdf/TruSeal_02.pdf

RE: Leaking Stainless Steel NPT Threads

Use a thread sealant or thread tape.  Pay attention to your torque value for NPT threads, they easily pick-up.

Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada

RE: Leaking Stainless Steel NPT Threads

Threaded SS connections and your pushing the limits of the 600# flange?  Something doesn't sound like it got put in right.

Zuccus

RE: Leaking Stainless Steel NPT Threads

Like Cockroach said, over-tightening NPT threads can be just as bad or worse as under-tightening.  

Megaloc made by Hercules Chemicals has worked for us in our low pressure application.

Reidh

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