Where to buy Delrin Seal

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ThomasT

ThomasT

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Apr 25, 2021
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Deep East Texas on Sam Rayburn Lake, United States
www.uncletomsplace.net
Hello everyone,

Where can I buy some extra Delrin Seals that fit into a 1/8" Foster fitting?

Thanks for the help,

ThomasT

Foster Delrin Seal.1625739620.jpg

 
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What about 1/4" food grade waterline tubes for freezer ice maker from HD?
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Hello bigHUN,

I think that material would not be strong enough, really not sure. Delrin is pretty hard material and does not compress very easily.

Thank you,

ThomasT
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I have a seal in a transfer port in my franken project. The ring is enclosed and won't go anywhere and if you let it alone there is no wear in flatness...you pretty much no need for delrin any nylon would work....but up to you.
 
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First, the OP has mis-identified the thread. It is not NPT. NPT threads seal on the thread. What you have is 1/8" BSPP. British Standard Pipe Parallel threads seal with seals either at the top with a flange or at the bottom in your case. However not all nylons work as a seal, as they have a tendency to flow under compression over time and lose the seal..You would be better off using a phenolic fiber , soft aluminum or soft copper washer.
 
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First, the OP has mis-identified the thread. It is not NPT. NPT threads seal on the thread. What you have is 1/8" BSPP. British Standard Pipe Parallel threads seal with seals either at the top with a flange or at the bottom in your case. However not all nylons work as a seal, as they have a tendency to flow under compression over time and lose the seal..You would be better off using a phenolic fiber , soft aluminum or soft copper washer.
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Hello steve-l,

You are incorrect about the threads that are on the fittings that I have, they are NPT. The thread count and pitch are to NPT standards. I do have some British threaded fittings on the air cylinder that I purchased from Best Fittings from the UK. I used an adapter that is threaded BSPP one end bye NPT other end to connect to my system. Delrin is not NYLON, Delrin® is the DuPont registered trademark for its brand of acetal resin also commonly referred to as polyoxymethylene (POM).

Have a great day,

ThomasT
 
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Hi Thomas,

I'm not there, so I cannot be certain of course, but all tapered pipe threads (NPT or BSPT) seal on the threads. NPS and BSPP seal with washers.In the 1/8 size the pitch is almost the same, 27 vs 28 TPI and it is very difficult to differentiate. I do stand by my advice for washer material though. I have had too many washer failures with those plastic washers.


 
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Hi Thomas,

I'm not there, so I cannot be certain of course, but all tapered pipe threads (NPT or BSPT) seal on the threads. NPS and BSPP seal with washers.In the 1/8 size the pitch is almost the same, 27 vs 28 TPI and it is very difficult to differentiate. I do stand by my advice for washer material though. I have had too many washer failures with those plastic washers.

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Hello again Steve,

All my fittings are marked either NPT or in the case of a "Foster" fitting will be marked ( in this case ) 12FPS. If you will read the specifications on the Foster page, it shows the threads on a 12FPS is female pipe. 

Also if you read the American Standard specifications for "sealing" standard pipe threads it requires a "compound" to be applied to the threads. Buna-N material is used throughout the industry as a seal material mainly because a fitting can be taken apart and reassembled using this for a seal. Whereas a "compound" must be re-applied if the seal is broken. Delrin ( Acetal ) does the same job as Buna-N but has some favoring properties in some applications. My personal choice for this just happens to be Delrin.

I appreciate your personal choice for whatever requirement you may have.

Be safe and have a great day,

ThomasT
 
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