With the development of high-tech industries, a variety of valves are often used in everyday life. As check valve suppliers share with you the difference between globe valves and check valves.
What is a Globe valve?
A globe valve, unlike a ball valve, is a valve used to regulate the flow in a pipeline and consists of a movable plug or disc element and a ring seat fixed in a roughly spherical body. The globe valve is named after its spherical body, the two halves of which are separated by an internal baffle. It has an opening that forms a seat into which a removable plug can be screwed to close (or shut) the valve. The plug is also known as a disc. In globe valves, the plug is attached to a stem which is operated by screw action via a handwheel in a manual valve.
Working Principle of Globe Valve
Globe valves are popular due to the low friction between the sealing surfaces when closing, their long service life, low lifting height and ease of manufacture and maintenance. Globe valves are not only suitable for low and medium pressures, but also for high pressures. The working principle of the globe valve is to rely on the pressure of the valve stem to make the sealing surface of the butterfly seat and the sealing surface of the valve seat tightly bonded, preventing the medium from passing. The ball valve only allows the medium to flow in one direction. Therefore, globe valves are directional when installed. The globe valve end face size is larger than the gate valve end face size. At the same time, for high fluid resistance globe valves, the sealing performance is poor during long-term operation.
What is a Check valve?
A check valve is a valve that normally allows fluid (liquid or gas) to flow through it in only one direction.
Check valves are two-way valves, which means that they have two openings in the valve body, one for the fluid to enter and the other for the fluid to leave. There are several types of check valves for various applications. Check valves are often part of common household items. Although they are available in a wide range of sizes and costs, check valves are usually very small, simple and inexpensive. Check valves work automatically and most are not subject to human or any external control; therefore, most do not have any valve handle or stem. The body (housing) of most check valves is made of plastic or metal.
The working principle of Check valve
The check valve working principle is based on allowing flow in one direction and automatically preventing flow in the reverse direction. The check valve is made of metal. When the pressure on the inlet side is lower than the pressure on the outlet side, the valve automatically closes the passage under fluid pressure and its own gravity, preventing the flow in the reverse direction. According to the different ways of valve movement, check valves can be divided into three categories: lift check valves, swing check valves and butterfly check valves.
Check valves are designed to prevent water from flowing back under high pressure to the pump impeller in the pump water supply system. When the system is running, if the pump suddenly stops running for some reason, the pump pressure will disappear and the high pressure water connected to the pump outlet will flow backwards towards the pump. When the pump outlet is equipped with a check valve, the check valve will immediately close, preventing the high-pressure water from flowing back into the pump. Otherwise, the high pressure water will flow backwards towards the pump and the pump impeller will reverse under the impact of the high pressure water. It may also cause the pump impeller or other spare parts to become loose or damaged. When the pump runs again, this may cause the impeller to fly out, posing a significant threat to safe production.
Differences between globe valves and check valves.
1. Check valves and stop valves are not the same thing, the difference between the two mainly lies in the structure is very different.
Check valve is a one-way valve, automatically stop the reverse flow of fluid, no knob, can not artificially block the forward flow.
3. The stop valve has a knob and can be artificially controlled in the forward flow. Due to its special structure, the fluid cannot flow in the reverse direction even without an artificial pipe valve.