Comparative analysis of shut-off valve designs of domestic water supply systems
The modern market of household plumbing offers a wide variety of designs of shut-off valves suitable for installation and subsequent operation in domestic conditions. Each design has its own characteristics.
Classification
Shut - off valves are distinguished by the following parameters:
- According to the method of fastening – angular or straight-through;
- By material – stainless steel or copper alloys (brass, bronze);
- By bandwidth;
- By overall dimensions.
The choice of a suitable design is always made for specific application conditions. This provides convenience in the subsequent replacement or repair of the considered water supply devices.
Valve selection by mounting method
Shut-off valves with threaded mounting can have many options, but the most common is a small-sized valve with an oval handle with ribbed edges for gripping. Inside such valves use a compression rod (in such types, when the valve is closed, a "compression" of the flow is felt), but more often there are constructive solutions that include a small ball. With its help, a short (no more than a quarter turn) turn of the handle transfers the valve from a fully open to a fully closed position.
Fastening shut-off valves allow various ways of attaching to pipes (for example, they are often glued to plastic mains), but compression fittings that slide along the pipe and tighten in place are more common.
The installation of such elements can be angular when the water pipe comes out of the wall. Then the angle should be formed at the top to perceive the water supply from the pipes through the fittings to the faucet sink or toilet valve.
The next type is a direct shut–off shut-off valve, which works in the same way, but is intended for use when the water supply pipe exits from the floor, and not from the wall.
Valve selection by design
Let's analyze the pros and cons of ball and rotary shut-off valves.
Compression valves are multi-turn, they are equipped with a rod with a rubber washer at the end, which is attached to the valve handle. When turning, the stem moves into the valve cavity, pressing the washer against the inner seat and forming a seal.
Ball valves were developed later. To activate them, it is enough to combine two holes – in the ball and the pipe, for which it is sufficient to rotate the control by 900.
Which design is better? When a leak is detected in the rotary valve due to a deterioration in the quality of the seal, it can be replaced (sometimes it is enough to strengthen the stem seal, for example, with a FUM tape) or simply tighten the adjusting nut on the valve.
With a ball shut-off valve, the situation is worse: if water leaks, it will have to be completely replaced. This operation must be performed correctly to avoid the phenomenon of hydraulic shock. The trouble with the water hammer is that with a sharp opening/when the ball valve is closed, the water flow is immediately thrown into the faucet or stops in the pipe. This is accompanied by vibrations, noise, and, ultimately, can lead to an accident on the pipeline (especially if old metal or plastic pipes were used for its laying). Therefore, for the installation of ball valves, it is better to invite a plumber with a license to perform such work.