Hydraulic fittings are driving me crazy!

   / Hydraulic fittings are driving me crazy! #1  

TRUST

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kubota 2620 HST
On a NPT male thread when looking at the end of it, some are cut flat and others are cut with an inward bevel. How do you know if the bevel is going to be on a given fitting if ordering online or over the phone? Some of the fittings I need show a picture from the other end of the fitting:mad: Is there a descriptive term used to designate that inward bevel? I have a NPT female swivel fitting that will need that type of male end to seal properly. (I'm doing some shopping at burden sales surplus) Here one of the fittings I'm looking at.
Burden Sales Surplus Center Item Detail
I called, but the tech dept. went home early:mad::mad:
Thanks
 
   / Hydraulic fittings are driving me crazy! #2  
I have a NPT female swivel fitting that will need that type of male end to seal properly. Thanks


On a NPT thread, the threads are the means of sealing. There is no seat.
 
   / Hydraulic fittings are driving me crazy! #4  
I know exactly what your talking about, it seems like the higher quality fittings have the correct inside bevel for a swivel fitting, the cheap knock-offs don't have it, i don't know much more than that, i used to deal with weatherhead fittings and they all had the correct beveling!!! they should designate that somehow especially when trying to order online, you never know what you are going to get!!!
 
   / Hydraulic fittings are driving me crazy! #5  
On a NPT male thread when looking at the end of it, some are cut flat and others are cut with an inward bevel. How do you know if the bevel is going to be on a given fitting if ordering online or over the phone? Some of the fittings I need show a picture from the other end of the fitting:mad: Is there a descriptive term used to designate that inward bevel? I have a NPT female swivel fitting that will need that type of male end to seal properly. (I'm doing some shopping at burden sales surplus) Here one of the fittings I'm looking at.
Burden Sales Surplus Center Item Detail
I called, but the tech dept. went home early:mad::mad:
Thanks

You are confusing NPT with ORB I think... ALL NPT threads are tapered so as the fitting is tightened it gets harder to turn.

The "flat-cut" as you say are SAE type (also called ORB for O ring Boss) like THIS


Don't worry about the picture...If it say NPT then you are good to go;)
 
   / Hydraulic fittings are driving me crazy!
  • Thread Starter
#6  
Perhaps I'm not being clear. I am NOT referring to the "taper" of the NPT threads. I'm talking about the "back bevel" that is machined on the INSIDE of the male end. Enlarge the pic to see where I'm talking about. Some NPT have this, some do not. What gives?
 

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   / Hydraulic fittings are driving me crazy!
  • Thread Starter
#7  
I know exactly what your talking about, it seems like the higher quality fittings have the correct inside bevel for a swivel fitting, the cheap knock-offs don't have it, i don't know much more than that, i used to deal with weatherhead fittings and they all had the correct beveling!!! they should designate that somehow especially when trying to order online, you never know what you are going to get!!!

You seem to know what I'm talking about. Look at my last post and see If were on the same page.
 
   / Hydraulic fittings are driving me crazy! #8  
Joel,
That taper is only required when you are connecting to a swivel-type fitting like referenced by LiquidWrench in the post above. Usually the only thing connected to that side of the swivel is a hose...and all the hose ends have it.
 
   / Hydraulic fittings are driving me crazy!
  • Thread Starter
#9  
Joel,
That taper is only required when you are connecting to a swivel-type fitting like referenced by LiquidWrench in the post above. Usually the only thing connected to that side of the swivel is a hose...and all the hose ends have it.

Exactly!:)

But if you want to put a fitting in the swivel end and not a hose end, how do you know if the fitting is going to have the bevel or not? In this case I need a bushing to reduce from a 3/8 NPT female swivel to 1/4 NPT male hose end. You can find fittings with the bevel, I got one recently. I had to go to a shop and show them in person what I was talking about. It's the one on the left. Sounds like I'll have to buy it locally. I didn't want to do that since the cost is substantially less online.
 

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   / Hydraulic fittings are driving me crazy! #10  
On a NPT thread, the threads are the means of sealing. There is no seat.

-Except- on the case when you mate a swivel.. in which case the thread deformation is not the sealing spot.. but rather a set and face... .. which is the exception the OP stated...

soundguy
 
 
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