Category: Industrial valves knowledge

The double eccentric sealing butterfly valve adopts an eccentric structure design. The main structure of the valve is composed of valve body, butterfly disc, valve seat, valve stem and transmission mechanism. The valve seat adopts a detachable structure and can be based on the physical and chemical properties of different media. Corresponding corrosion-resistant, light-resistant, and aging-resistant materials are selected, which can be widely used in fluid pipelines such as water supply and drainage, sewage, construction, air conditioning, petroleum, chemicals, food, medicine, textiles, paper making, hydrpower, ships, metallurgy, energy systems, etc. Used as a regulating and intercepting device.

Flange connection is composed of flange, gasket, bolt and nut connection. It is a detachable connection that can be used to connect pipes and valves, pipes and pipes, and pipes and equipment. The flange connection not only has the flexibility of installation and disassembly, but also has reliable sealing performance, high strength, simple structure, low cost, and can be repeatedly disassembled. Because the flange has good comprehensive performance, it is widely used in basic projects such as chemical industry, construction, water supply, drainage, petroleum, light and heavy industry, refrigeration, sanitation, plumbing, fire fighting, electric power, aerospace, shipbuilding and so on.

All industries are now trying to find ways to reduce costs, and the valve industry is no exception. Some bosses in the valve industry find that the cost of valve design has a greater impact on their overall cost when reducing costs. So how does the design cost of the valve affect the overall cost of the valve? Let’s take a look together

The check valve is used in the pipeline system, and its main function is to prevent the medium from flowing backward, preventing the pump and its driving motor from reversing, and releasing the medium in the container. Check valves can also be used to supply pipelines for auxiliary systems whose pressure may rise above the pressure of the main system. According to different materials, check valves can be applied to pipelines of various media. The check valve is installed on the pipeline and becomes one of the fluid parts of the complete pipeline. The opening and closing process of the valve disc is affected by the transient flow state of the system where it is located; in turn, the closing characteristic of the valve disc have an effect on fluid flow again

Butterfly valves are suitable for flow regulation. Since the pressure loss of the butterfly valve in the pipeline is relatively large, it is about three times that of the gate valve. Therefore, when selecting the butterfly valve, the influence of the pressure loss of the pipeline system should be fully considered, and the strength of the butterfly plate to withstand the pressure of the pipeline medium should also be considered when it is closed. In addition, it is necessary to consider the limitation of the working temperature of the elastic seat material at high temperature.

The valve can be installed on the flange only after the flange is welded to the pipe and cooled to ambient temperature. Otherwise, the high temperature generated by welding will affect the performance of the elastic valve seat.

After the valve is closed for 4-6 hours, use an infrared temperature measuring instrument to measure the temperature of the valve stem (near the valve body) or the metal temperature 150mm downstream of the valve body. If it is greater than 70°C, it is regarded as “internal leakage”. This judgment method is applicable to most internal leakage valves.

Seal elements are frequently used sealing parts for machinery and equipment, and are materials that play a sealing role. From this definition, it is not difficult for us to know how important the seal element is, so how to install the seal element is worthy of our attention. The correct installation can ensure the sealing performance and make the equipment run smoothly, otherwise it will damage the sealing seal element. Next, let’s take a closer look at what should be done.

The materials for manufacturing valve parts should be selected according to the following factors

1. The pressure, temperature and characteristics of the working medium.
2. The force of the part and its function in the valve structure.
3. It has better manufacturability.
4. If the above conditions are met, there must be a lower cost.