Is there a way to get this valve working?

baj702

This is a huge valve, I think it is ~5" pipe. It hasn't worked for a least 20 years. I tried turning is with a 3 foot pipe wrench but I was afraid to put too much pressure on it - for fear I would be in worse shape that if it just didn't work. Maybe something like a rebuild kit? Also, is it opened or closed?

pecmsg

What’s it holding back?

baj702

This is a valve just after the header, shuts off steam to the main, I think they'e called king valves?

pecmsg

You’re going to have to dismantle it. 

Pull the packing
pull the top bell
take it apart and
clean
clean
clean

EdTheHeaterMan

If it is holding back toxic radio active cooling water from the nuclear power plant, what's the worst that could happen? Get a bigger wrench, with a bigger cheater on the handle.

mattmia2

There is a good chance the packing may be asbestos so you probably want to take that part apart where you can keep it wet and contain it.

Jamie Hall

That is an eye-wateringly expensive valve. Further, even if you can repair it -- which I wouldn't guarantee -- you won't be able to do it quickly. So... if you can't wait until the whole system is down. I'd prepare a flanged spool piece to fit and take the thing out and the spool piece in and take it to a workshop to work on at my leisure.

Do you even really need a king valve?

EBEBRATT-Ed

That old valve with threaded ends would be a tough replacement. You would have to cut it out and have flanges welded in.

Looks like a gate valve. I would take the 6 or so bolts out and pull the whole assembly out of the valve body so you can work on the innards on the bench,

We used to do that when installing a heavy valve with tight access. Install the body and then put the gut's in saves lifting all the weight at once.

you can easily make a new gasket which you will need,

If you put a big wrench on the stem you will break it.

It's probably rusted up on the inside from condensate laying in the valve in a vertical position

EBEBRATT-Ed

Once you get the guts pulled out you could install a temporary plate where the valve body bolts on if you need to keep the system running

baj702

@Jamie Hall Well, they're nice when you need to build up some pressure to clean out the boilers. I was thinking about trying to get it working this summer - I'm in no rush.

retiredguy

That valve looks like a 3" or possibly an old 3.5" non-rising stem Walworth gate valve. I can't tell from that picture. The size is usually indicated on the side of the valve body. If I were doing the repair, I would do it in the spring or when that part of the system is shut down. I have replaced Flanged valves up to 12" but that screw valve would be a nightmare to replace unless you have the expertise and the necessary equipment. I recommend that you do a "search" for a valve repair shop and have them do the job. Most valve shops can do a fair rebuild "in place", or if you do not need or use that valve to isolate that line, let it alone.