The quality of china gate valve installation directly affects its use, so it must be taken seriously. Many gate valves have directionality, such as globe valves, throttling valves, pressure reducing valves, check valves, etc. If they are installed upside down or reversed, it will affect their effectiveness and service life (such as throttling valves), or even have no effect (such as pressure reducing valves), and even cause danger (such as check valves). Generally, gate valves have direction indicators on the valve body; if not, they should be identified correctly according to the gate valve's working principle.
The position of the gate valve installation must be convenient for operation; even if the installation is temporarily difficult, it should be considered for the long-term work of the operators. The handwheel of the gate valve should be aligned with the chest (generally 1.2 meters away from the operating floor). This way, opening and closing the gate valve is easier. The handwheel of the rising-stem gate valve should be facing upwards and should not be tilted, to avoid awkward operation. Hosenbock reminds you: gate valves located next to walls or equipment should also leave space for operators to stand. Avoid operating with your head up, especially for acid and alkaline, toxic media, which is unsafe.
Do not install the gate valve upside down (i.e., with the handwheel facing downwards), otherwise the medium will stay in the valve cover space for a long time, which is prone to corrode the valve stem and is also taboo for some process requirements. At the same time, replacing the packing is very inconvenient. Rising-stem gate valves should not be installed underground, otherwise the exposed valve stem will corrode due to humidity.
Description
The gate valve has a flat closure element that slides in the flow to open or close the valve. In the bronze valve body commonly used in commercial and residential applications, the bronze disc moves up and down to open and close the valve. The valve is designed to keep the brass stem at the same height relative to the disc movement. A polytetrafluoroethylene packing is used in the threaded cap to prevent leaks around the valve stem. A manual valve is driven by rotating a cast iron handwheel.
The ball valve has a spherical closure element with a hole that is circular or other shapes. Aligning the hole with the flow opens the valve and closes the flow of solids outside the ball. The ball sits on the valve seat and the stem is inserted into the top of the ball. The filling and gasket around the stem prevent leaks. There are two ports in the port gate valve, an inlet and an outlet. The above gate valve has threaded ports, although welding and flange connections are also available. The ball valve for sale has two or more ports. The same selection is provided by connecting to the port. A ball valve made with three ports is used as a mixing or diverting valve.
Flow Characteristics
The flow of a partially gate valve open is proportional to the movement of the closure element. This limits the availability of gate valves to actively control the flow of the medium, so gate valves are mainly used as shut-off isolation devices or pipeline sections.
The design of the ball valve allows the flow to be proportional to the rotation of the closure element. This is called "modified equal percentage" flow characteristic. This makes the ball valve suitable for actively controlling the flow of the medium.
Drive
The gate valve is ideal for isolating general-purpose flows, and operating is rare in high-pressure and high-temperature applications. For this reason, manual operation is typical, generally through multiple turns of handwheel components, although mechanical, pneumatic and electric actuators are also available.
Gate valves are valves that can be opened and closed and can only be fully opened or fully closed, and cannot be used for adjustment. If the gate is opened to a perpendicular state with the flow, it means it is closed. Its main role is to close and open. When the gate valve is closed, it can seal through the pressure of the medium.
The gate valve also has different materials that can be used for water, steam, and various liquids such as oils or oxidizing media. The applicable pressure range, temperature, is relatively wide, and it will not be limited by the flow direction. It can also bring very good sealing performance. The gate valve is relatively easy to operate when switching and has a wide range of applications.
