China has produced and applied cast iron valves for nearly 100 years, but significant development has been the case in the last 10 years. According to relevant statistics, the annual output of domestic cast iron valves and fittings has increased from 800,000 tons to 2,000,000 tons in the past 10 years, with an average annual decline rate of about 20%.
Common manual valves, including ball valve, gate valve, globe valve, butterfly valve, plug valve, etc., are the most widely used valves. Their handwheels or handles are designed according to ordinary manpower, taking into account the strength of the sealing surface and the required closing force.
The gate valve is a valve that moves the shutter closure member in the vertical direction of the centerline of the passage. Generally, it consists of valve body, valve seat, valve stem, gate, valve cover and sealing ring.
The structural characteristics of the high temperature and high pressure Y type globe valve are as follows: 1. The wide sealing surface design can effectively extend the service life of the sealing surface. The sealing surface is welded with STL alloy, which is good in erosion resistance and wear resistance.
If the valve flap of the safety valve and the seat portion of the valve seat are leaked beyond the rated range, the loss of the medium may occur, thereby destroying the sealing material. Under normal circumstances, the sealing surface of the safety valve is mainly composed of metal material, and it is smooth and flat as much as possible.
Valve daily maintenance is very importance, following are some instructions for valve daily maintenance.Doing these tasks well is believed to be very helpful for prolonging the service life of the valve, and it can also reduce a lot of unnecessary troubles.
Control valve requirements: control boiler water intake, ensure steam evaporation, maintain boiler water level, that’s attached boiler feed valve system contains two control valves, one for boiler start-up, one for normal water supply.
In recent years, with the continuous improvement of China's comprehensive national strength, the development of China's marine industry has also achieved rapid progress. In this context, the shipbuilding industry has drawn much attention.
Fugitive Emission Valves are those valves which bleed only a small amount of leakage to the external environment.In some European countries, there are customized companies to provide Fugitive Emission Testing Service for the local manufactures and end users.
The pneumatic diaphragm regulating valve has the advantages of compact structure, lightweight, sensitive action, fluid type, less pressure drop loss, large valve capacity, accurate flow characteristics, convenient assembly, and disassembly.
