shutoff valve install

I need to install a shutoff ball valve onto a horizontal run of copper water pipe where one currently does not exist. I plan on measuring the distance between the end of the valve inlet and the end of the valve outlet and then subtracting from that distance the distance that the connecting inlet and outlet pipes will insert into the valve in order to determine what length I will need to cut out of the pipe so that when I install the valve there will still be the same length in the run of pipe. In other words, I want to minimize or eliminate the need to either push or pull the run of pipe to install the valve and want to keep the same length of the run of pipe after the valve is installed. Is the method as I describe the typical way it's done, or do I have it mixed up and there is a better way? Any comments/advice please?

 

Some movement is usually needed to make things fit correctly. If not horizontally, then vertically. The pipe fits inside the valve body, so something will have to move. Even compression type connections require the pipe to be inside the valve body.

 

Hi, This is how I would do it. Get the valve and a repair coupling. Cut the pipe where you want the valve then cut the pipe about 6" up line. Put the 6" pipe in the valve then put the valve on the end of pipe, mark the pipe where the 6" pipe ends. When you are satisfied with the fit remove the pieces clean and flux, slide the coupling on the end of the pipe where the 6" pipe meets the other pipe and solder the system up.
Good Luck Woodbutcher

 

Thanks for replies. Woodbutcher method seems to make good sense to install a valve into a section of run where one previously did not exist. The simple addition of a coupling into the assembly, as he described, would allow for proper fit with minimal lengthening or shortening of the line.
Also, in another place I need to replace a 1 1/4 inch bad old gate valve with a new ball valve. I want to sweat the new valve where the old valve is located instead. I noticed the old gate valve is a good inch shorter than the new ball valve. What's the most sensible procedure to accomplish this replacement? What do I measure, where should I make the initial cut(s) in the line, and where and how might couplings come into play? Thanks.

 

to use the method woodbutcher suggested you'll still need the pipes to move a little bit. if they won't budge in any direction you'll need to use 2 repair couplings and just cut a 12" section out. then follow the steps he laid out for both sides.

for the 1 1/4" valve i'd approach it the same way. just cut the valve out and some pipe on either side. then fit the valve to one end and measure the missing section. then use a repair coupling to finish it all up.









paul