Almost every family now uses tap water, but when we use tap water, we need a valve to control the switch, and then there is generally a total gate, but many do not know the direction of turning, so how to judge? Today we come to understand how the ball valve judges the switch? How to choose a valve? Let's take a look at the relevant knowledge, I hope it can be helpful to everyone.
How to judge the switch of the ball valve
If it is an electric, pneumatic, worm gear drive ball valve, it can be seen from the indication plate. For example, when the handle drive ball valve is generally in the same direction as the pipe flow, the valve opens, otherwise the valve closes.
How to choose a valve
1. When purchasing, check the valve visually, the surface should be free of blisters; the plating surface should be evenly glossy, and attention should be paid to defects such as peeling, cracking, carbonization, bottom exposure, peeling, black spots and obvious dents; the sprayed surface should be good. It is smooth and uniform, and there will be no defects such as sagging and exposed bottom. The above defects will directly affect the service life of the valve.
2. The pipe thread of the valve is connected to the pipe. When purchasing, visually inspect the thread surface for obvious defects, such as dents and broken teeth. It is important to note that the effective length of the pipe thread and the connecting member will affect the reliability of the seal. Gender, pay attention to the effective length of the pipe thread when buying. Generally, the effective length of a cylindrical pipe thread of DN15 is about 10mm.
3. Gate valves and ball valves are usually marked with a nominal pressure on their valve body or handle. When buying, you can choose according to your needs.
4. When replacing an existing gate valve or ball valve, the length of the structure must be clarified to avoid installation after purchase.
5. The pipe thread of the triangle valve has two kinds of internal thread and external thread, which can be purchased according to your needs. Also noticed that there are some triangle valves made of zinc alloy on the market. The price of the valve is lower than that of ordinary products, but it is corrosive It also causes damage. It should be purchased at a regular building material store or supermarket to ensure the quality of the product.
