The work of the plumber is divided into two distinct lines - drainage and supply.
In nearly all city work, the drainage system must be installed according to plumbing ordinances established for the purpose of securing uniformly sanitary work.
The supply system, however, in most cases is not thus protected by municipal ordinances, although in some of the more progressive cities it is now safeguarded in the same manner as the drainage system.
There was a time when nearly all supply piping was of lead. To-day, however, the use of this material has been very largely displaced by the use of brass and galvanized wrought iron. It may be stated, however, that in some sections lead pipe is still used almost entirely for supply work, generally in such cases, owing to the chemical properties of the water supply.
Some waters will attack lead pipe more seriously than wrought iron, while the reverse may be true of other waters.
Thus, in some sections galvanized piping will fill with rust and sediment in a very few years, while over the surface of lead pipe a sort of protective coating will form, which will allow its continued use for an almost unlimited length of time. The author has known of instances where wrought-iron pipes and galvanized boilers could be used only four or five years before being made entirely unfit for use, the pipes becoming almost completely filled and the boiler rusted through.
On the other hand, he has seen galvanized supply piping taken out that has been in use for twenty to thirty years, which was very nearly as clear as when first installed.
When pipe is to be laid underground, and the quality of the water will possibly permit, it should be lead rather than wrought iron, as the former has a much longer term of life when subjected to the corrosive influences incident to the moisture of the ground.
For this reason, service pipes, even though of wrought iron, are usually connected to water mains by means of lead connecting pieces. Such connections are to be seen in Fig. 248. The upper connection made without lead is wrong, for it is very rigid, and liable to be broken off, whereas the lead connection will give sufficiently to take up any such strain.
Fig. 248. - Service Connections.
From the lead connection the service pipe is carried to the curb, where a service stopcock is usually located. It being necessary to close this stopcock from the street, a curb box, as it is called, is usually made use of, as shown in Fig. 249.
Fig. 249. - Shut-off on Service Pipe and Curb Box.
The curb box is so made that it may be varied in length to suit different depths at which the stopcock is located.
The bottom of the box is slotted so that it may set down over the pipe, resting on the earth beneath the pipe. To the stopcock is connected a rod which extends to the top of the box passing through the cover of the box and ending in a five-sided head. To * open or close the cock, a socket wrench, made to fit this head, is used. A five-sided head is used instead of a square or hexagonal head, in order that only those connected with the water department and supplied with a special wrench may be able to operate the stopcock.
Fig. 250. - Stopcock and Stop- and Wastecock.
From the curb, the service pipe is carried through the foundation wall of the house. Just inside the foundation, the main supply pipe should be provided with a stop- and wastecock. In Fig. 250 is shown an illustration of the plain stopcock, also an illustration of the stop- and wastecock.
In the latter a small round waste opening will be observed. When the handle is turned to close this cock, the water in the piping, which is shut off by the closing of the cock, wastes out through the waste opening. By means of a small lead pipe, connected to the waste opening, this water may be conveyed if desired, to some open fixture, instead of being allowed to waste onto the cellar bottorn or into the ground. The use of the stop- and wastecock is a very important matter in many places where water, if allowed to stand in the piping, is liable to freeze and burst the pipe. For this reason, the main stopcock on a main house supply, should be a stop- and wastecock, in order that the entire supply piping may be drained, a very important matter if the house is to remain vacant during cold weather. This cock should always be placed in a position which will be easily accessible in the event of an emergency. It should also be fully protected against frost, so that the cock itself and the pipe beyond it may not freeze. In warm cellars, precautions of this nature are often unnecessary.
Fig. 251. - Deep Trap in Water Piping.
If necessary, however, the cock may be protected by means of boxing, hair felt, etc. The plumber in running his water piping should always be sure to run it so that no traps may be formed which will not drain off through the main stop- and wastecock.
For instance, in Fig. 251 the deep trap formed by running the branch down from the overhead line, and then up to the fixture, forms a trap which cannot be drained through the main stop- and wastecock.
If any pipe must of necessity be run in this manner, a pet cock or faucet should be placed so that when required this part of the piping may be drained. The running of pipes in this way is quite a common error, being often found on the hot-water piping especially. In order that the pipes may be thoroughly drained, they should always pitch down in the direction of flow toward the main stop- and wastecock.