The New Nested Forged Steel Ball Valve

The New Nested Forged Steel Ball Valve

Jan 26, 2021

Research on the new invented nested forged steel ball valve
1. Defects of traditional ball valves
First, the biggest drawback of traditional ball valves is that great friction and torque will be generated when the ball rotates. When the valve is opened or closed, the opening and closing torque is too great, which affects the opening speed. If the rotating torque is too great, the connection between the valve stem and ball is easily damaged. There is great friction when the valve is opened or closed, which leads to accelerated wear of the sealing pair and short service life. Under the working conditions of high temperature, high pressure and special medium, especially in the case of automatic control, the opening and closing torque is too great, which also directly affects the reliability, durability and safety of the ball valve. Second, for ball valves with large diameters and multi pieces, the valve leakage point is added; mechanical processing procedures are many; the processing volume is much; the product assembly procedures are complex and the work efficiency is low. Third, materials have low utilization; manufacturing costs are high and the added value is low. For this reason, a new invented nested forged steel ball valve is successfully developed based on hydraulic principles and fluid mechanics theories and years of rich experience in valve research, development, design, manufacturing and sales, and the structure diagram is shown in the figure 1.
2. The key technology of the nested forged steel ball valve
(1) Straight-through nested forged steel ball valves adopt straight-through valve bodies and flanges, which changes the traditional multi-piece valve body, the valve body and flange being separated and processed and then assembled into an integrated structure, reduces the leakage point of the valve body and avoids the leakage caused by the multi-piece valve body.
(2) The innovation of the bonnet is a one-piece bonnet with a bonnet and a flange, which changes the traditional structure of processing bonnets and flanges and then assembling them, effectively reducing the leakage point of the bonnet.
(3) The sphere is nested. Provide conditions for the bonnet to adopt other materials and to obtain multiple seals. The bonnet can be made from materials that are one grade lower than the valve body. It does not affect product quality, and has the characteristics of good mold forming, high blank qualification rates, good processing technology and manufacturing costs being greatly reduced.

Figure 1 The schematic diagram of nested forged steel ball valve structure

1. Valve bodies ⒉ Seals 3. Springs 4. Spring seats 5. Seals 6. Valve seat assembly 7. Pins 8. Seals 9. Bearings 10. Balls 11. Nesting 12. Seals 13. Nuts 14. Studs 15&16. Seals 17. Packing sleeves 18. Nuts 19. Springs 20. Valve stems 21. Valve bonnets

(4) The sphere is innovated as a rotating shaft sphere structure. Bearings are installed at both ends of the rotating shaft to change the traditional sphere without rotating shaft structure. The sphere rotates lightly and flexibly, achieving the purpose of effectively reducing the opening and closing torque. It is more suitable for special media such as acids, alkalis, oils, media with high viscosity, fiber or granular, which expands scopes of applications.
(5) Both soft and hard sealing are used to adapt to different working conditions of different pipe systems. First is that the valve body and bonnet are designed as multiple sealing structure, and the sphere and nest also have multiple sealing structure. The traditional single sealing structure between the valve body and bonnet and between the sphere and nest is changed. At the same time, this lays a foundation for the valve bonnet being made from other materials. Second is that the innovative design of the sphere seal of the nested forged steel ball valve adopts the sphere nesting structure. A metal frame and a symmetrical elastic ring are set, and set a symmetrical soft seal or multiple seals at both ends of the stem. The third is that the innovated vertical axis rotating opening and closing parts adopt double seals or multiple seals, and the sealing is easy to obtain, which can effectively reduce the opening and closing torque of the valve.
The flow capacity of the flow channel which has the same diameter as the pipe is extremely great. It has features of small opening and closing torque, no destructive water hammers, high temperature resistance, small flow resistance, high pressure resistance, abrasion resistance, wide application ranges, one valve with multiple uses and no leakages. Moreover, the processing technology is good and the manufacturing cost is low.
3. The advantages of nested forged steel ball valves compared with similar valves at home and abroad
The new innovated nested forged steel ball valve can better solve the use problems of the rotation and sealing of balls, connections of the valve body and valve stem, torque, flow resistance, harmful water hammers and high temperature and pressure conditions. The nominal diameter of the ball valve is 50 to 900mm, which is six times bigger than similar valves at home and abroad. The nominal pressure can reach more than 42.0PMa, which is 3 times higher than similar valves at home and abroad. The hydraulic resistance reduction design is adopted, and the resistance loss is less than or equal to 1.0 to 1.5, which saves over 30% of energy materials than those of domestic and foreign. High temperature alloy castings are adopted instead of forgings for main materials of main bodies. The actual trial shows that the service life of main parts of ball valves is extended by 8 to 12 times, which is five times longer than the current casting technology at home and abroad. The medium temperature can reach -29 to 800℃, and similar products at home and abroad are generally 0 to 350℃. Moreover, the new nested forged ball valve has features of energy and materials saving, greatly increasing added value, excellent cost performance, safety and reliability, basically no maintenance, high temperature resistance, high pressure resistance, corrosion resistance and good scratch resistance. It is a veritable high-tech innovative valve, and its technical level is in a leading position in China.
Installation, use and maintenance
1. Installation
(1) Before installing the nested forged steel ball valve, read the product manual carefully.
(2 No dirt is allowed to adhere to the inner cavity and sealing surface of the nested forged steel ball valve.
(3 Drive the handle to rotate the valve ball to make the ball open and close flexibly. Configured driving devices should be used to open and close the valve for test inspection for all valves with electric, pneumatic and hydraulic driving devices.
(4) Test the pipeline with a gauge to determine whether the pipeline connection size matches the valve.
(5) Install the valve and tightly connect both ends of the ball valve with the pipe connection to prevent leakages.
(6) Drive the handle to open the ball valve, and open the valve to make the liquid flow in the pipeline system. If there is any leakage, eliminate it in time.
2. Use and maintenance
(1) The valve condition should be checked frequently during use, and the leakage should be eliminated in time.
(2) The following should be checked regularly: whether the seal is good and take necessary measures to repair it; check the wear degree of the valve stem and replace it if necessary; frequently observe the connection end of the ball valve and repair it in time if there is any leakage.
(3 When the nested forged steel ball valve is stored for a long time, it should be checked regularly. The processing surface should be coated with anti-rust oil and stored in a dry and ventilated room.
(4) It is strictly forbidden for staff without training to disassemble the nested forged steel ball valve.


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Launched in 1988, Topper Forged Valve Company is engaged in manufacturing forged steel valves. Our products cover Forged Steel Ball Valve, Gate Valve, Check Valve, Globe Valve, According to API, BS, DIN, JIS GB Standards.
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