Maybe they mean one end of the valve has the thread and the other end is plain end for socket welding.
This is then a drain or vent valve.

You mean PE is plain end. How it for socket welding?
The pipe is Socket weld?

Thanks

Don´t know exactly, but I think it´s like a valvolet(gatevalve)with a straight piece of pipe on one side and fem.thread on the other side(for a plug)

Hi,

PE stands for Plain End, which means that the end connection is a straight part (e.g. by means of a welded in Nipple or integral machined to forged body) with straight end, so no bevel machined to it.

This type of end connection specified for socket weld piping systems.

FNPT is indeed Female NPT on the other end.

Your valve is most probably a block valve before an instrument device.

Good Luck.

Hi FKE,

Thank you very much for the answer
I haven't seen this type before.
Please confirm whether is attached type.

Thanks a lot.

Kirby
KCYST VALVE

• http://files.engineering.com/getfile.aspx?folder=244654c1-782a-4714-bf0c-e8

Hi,

Yes the sketch shows the correct type. Note that the PE part must have sufficient length in order to avoid melting of the soft seats/seals and to enable execution of welding.
Normally a minimum length of 75 to 100mm will be applied.

Success.

Typically I see the designation PEBFW (Plain End, beveled for weld).  In the picture that was posted it just showed a plain end without a bevel.  Does anyone know what someone would do for a valve with a plain end that close to the body?

David

Just a guess here, but from that diagram, it looks like one can"

- tap the PE?
- undo the top bolts and swing the body down while welding?

"Do not worry about your problems with mathematics, I assure you mine are far greater."   
Albert Einstein
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I worked in a plant that had all the small valves welded on the process end.  The valve body had as part of the forging a piece about 6 pipe diameters long that was beveled for welding to a weldolet on the line.  The other end was threaded for connect to instruments and such.  A 1" valve was about 10" long.

Dcasto,
I've seen those too, but I just can't see a use for the plain end on the picture.

Ashereng,
That may be right, but WHAT A PAIN.

David  

We see some of these in sour service, where the requirement is for welds off of the pipe, but NPT after that.

"Do not worry about your problems with mathematics, I assure you mine are far greater."   
Albert Einstein
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Zdas04, me too. The plant standards were mostly from Belgium and applied here in the US.  From the PExMPT valve to the insturment was all 1/2" hard pipe, no tubing. NO thread o lets allowed, I'd guess a problem with the threaded fittin on the line, then again, you still have a threaded fitting from the valve to the instrument.