The first thing done was to clear the area of the old wood post and turn off the water main.
The pipe was then opened and the water was allowed to drain from the pipe. Here you see one half of a Union as the other half was removed with the old pipe.
Because this union was here, removing the old pipe was FAST; it only took a minute. Realize that this is where a union could come in handy for quick repairs on many of your other projects.
The pipe was cut close to the wall to install an Elbow. But as it turns out the water was still draining slightly so I let it finish while I continued with the rest of the project. You never want water running into your new PVC welds or on the parts about to be welded. The water will cause the cement to dry prematurely OR it will create a small seam between the parts causing it to perpetually leak once pressurized.
After cleaning the parts with Primer (only the spots that will be welded together), I then applied PVC Cement, using it liberally (just enough so that it won't drip when connecting the two).
PVC primer is used to clean off the surfaces of the weld. The manufacturers use a releasing agent on their molds to prevent the molten PVC from sticking, this acts like oil and could prevent a good weld of the two pieces of PVC. The primer will also very slightly melt the PVC it makes contact with - something we want when welding.
PVC cement is then applied on top of the primer directly. The primer dries very rapidly and even if it doesn't, it doesn't matter. Quickly using primer and then going straight to the cement is normal and acceptable.
As you press the pieces together, twist them slowly if at all possible. Three reasons for doing this 1) It ensures that the pieces are completely inserted into one another, 2) it removes any air bubbles that might have become trapped between the weld, and 3) It spreads the excess PVC cement around the inner and outer welds: like bathtub calking. If welded properly, the PVC weld will be stronger than the pipe itself.
!! You may NOT turn on the water for
AT LEAST 1-hour after your last weld !!
Any sooner and the welds may break or leak.
Be patient and give it sufficient time to dry; overnight would be even better.
After inserting the two pieces of cemented pipe and twisting them together, hold the weld together with pressure for several minutes. Without pressure the cemented parts might slip out from one another. The applied pressure while the cement is drying ensures a strong weld.
Shown at the right, I welded an elbow onto my 10-ft piece of pipe (we're still using 1-inch diam.) and stood it up in place in order to estimate where I needed to make the cut. **Remember, I'm still dripping water and decided to do everything else before welding this elbow in place**
Here (right) the couple was installed, the reducer inserted, and finally the smaller 3/4" pipe was added that will connect to the valve. From this point forward all of my plumbing will be standard 3/4".
I like reducing before the valve since the valve costs much less for 3/4" compared to that of the 1". If you plan on having multiple hoses or sprinklers running simultaneously, bigger is always better so don't reduce the line unless you need to and then only where you need to reduce it. My plans just don't have the need (and I know I'll never be installing a sprinkler system for the pasture - that would be a bit much)
All of the pieces shown here were installed one at a time. All were first cleaned using the primer, then the cement, followed by slight twisting and pressure for several minutes. Be careful not to get dirt into the cement as you weld. If it does, start over with a new part. the dirt will cause the parts to 'score' one another and leak.
True union valves are also great if something happens to the valve such as sand or dirt scoring the ball in the valve. I've had this happen when sand got into a pipe and the valve was ruined; never completely shutting off. I ordered a new valve, unscrewed both unions (one on each side) and then inserted only the new center section into the problem valve section. The job was done in only a few minutes and I didn't need primer or cement; especially nice since it was an acid line.
When gluing the end of the valve always remember to slip the threaded retaining ring onto the pipe FIRST (!), then you can weld the socket fit. Trust me, it's really embarrassing when you forget the threaded ring when training someone new to do this.
This is the final step of this particular project. I covered the valve and buried it. Later I'll be placing a post next to the vertical pipe and continuing the pipe from the tee to the new watering troughs yet to be installed.
Having kept the sod together, I was able to use it to re-cover the dirt patch. In a few weeks no one will know anything was done. If I chose, I could have added an insulated cover to protect the pipe from freezing in the winter -- but that's not a serious problem for the Houston area.
You've just run through a basic pipe installation covering 90% of the work you'll probably ever do. Take your time in planning where you want to run your water and lay everything out before you start in order to cut down on extra trips to the store. Once you get started you won't want to stop. The total cost of this part of the project was only $12 because I already had the primer, cement, and valve cover from a prior gardening project at my home.
And this is the finished job (below). The pipe is clamped to the wood post, the new 3/4" full throat valve and an elbow, and a special nipple for a hose.
I tested it and it gives a great flow!
. . . . . . all I need now is a hose real on the wall