WHAT DO YOU KNOW ABOUT GLOBE VALVES？

The globe valve, also called stop valve, is a forced-sealed valve. When the valve is closed, pressure must be applied to the disc to force the sealing surface to not leak. When the medium enters the valve from below the valve disc, the resistance to be overcome by the operating force is the friction between the valve stem and the packing and the thrust generated by the pressure of the medium. The force to close the valve is greater than the force to open the valve. The diameter must be large, otherwise the valve top bending failure will occur. There are three types of connection: flange connection, screw connection and welding connection. After the self-sealing valve appeared, the medium flow direction of the stop valve changed from the upper part of the valve disc into the valve cavity. At this time, under the action of the medium pressure, the force to close the valve is small, and the force to open the valve is large, and the diameter of the valve stem can be corresponding To reduce. At the same time, this type of valve is also tight under the action of the medium.

 

Advantages and disadvantages of globe valves

Compared with the other commonly used globe valves in industrial production, in terms of structure, the stop valve is simpler than the former, which is easier to manufacture and maintain. In terms of service life, the sealing surface of the globe valve is not easy to wear and abrasion. There is no relative sliding between the valve disc and the seat sealing surface during the valve opening and closing process, so the abrasion and abrasion on the sealing surface is less, so the seal is improved. The service life of the pair of globe valves has a small valve flap stroke during the fully-closed process, and its height is smaller than that of the valve. The disadvantage of the stop valve is that the opening and closing torque is large and it is difficult to achieve fast opening and closing. Because the flow passage in the valve body is relatively tortuous, the fluid flow resistance is large, resulting in a large loss of fluid power in the pipeline.

Specifically, the advantages and disadvantages of globe valves are as follows:

Advantages of globe valves
1. Simple structure, easy to manufacture and maintain.
2. Small working stroke and short opening and closing time.
3. Good sealing performance, small friction between sealing surfaces and long life.
4, the structure of the cut-off valve body has straight-through, DC and right-angle. Straight-through is the most common structure, but its fluid resistance is greatest. DC fluids have low resistance and are mostly used for fluids with solid particles or high viscosity. Right-angle valve bodies are mostly forged and are suitable for globe valves with smaller passage and higher pressure.

Disadvantages of globe valves
1.The fluid resistance is large.
2. It is not suitable for medium with particles, large viscosity and easy to coke.
3. Poor adjustment performance.
4. There are different types according to different classification methods. The types of stop valves are divided into external thread type and internal thread type according to the position of the stem thread. According to the flow direction of the medium, there are straight-through, direct-current and angular. The globe valve is divided into sealing forms, and it has a packing-sealed globe valve and a bellows-sealed globe valve.
5. The bellows seal globe valve adopts the design of bellows seal, which completely eliminates the shortcomings of ordinary valve stem packing seals, such as aging, and easy to leak, which not only improves the use of energy efficiency, increases the safety of production equipment, reduces maintenance costs and frequent Maintenance also provides a clean and safe working environment.

There are many product descriptions about globe valve in the market. How to choose a cost-effective one from many products is a technical task. Jaze is a better choice, where there is a variety of related valve products to be choosed, including ball valve, different concentric reducer and blind flange, etc,. Attached are some photos of detail of the stop valves and the website of company, please contact us in need.

https://www.jz-pipe.com/products.html