Zhuo Zheng's stainless steel ball valves generally have both reduced diameter and non-reduced diameter channels. Regardless of the structure, the flow resistance coefficient of the ball valve is relatively small. In particular, the so-called full-flow type, that is, the ball valve which does not reduce the diameter, has a channel diameter equal to the inner diameter of the pipe, and the local resistance loss is only the frictional resistance of the pipe of the same length, that is, the flow resistance of the stainless steel ball valve is the smallest among all the valves. In the rocket launch and its test system, the smaller the resistance of the pipeline is required, the better. There are two ways to reduce the resistance of the piping system: one is to reduce the fluid flow rate, and to increase the diameter of the pipe and the valve diameter, which often has an adverse effect on the economics of the piping system, especially for low-temperature conveying systems ( Liquid hydrogen) is extremely disadvantageous. (1) Reducing the local resistance of the valve, therefore, the stainless steel ball valve is naturally the best choice. (2) Stainless steel ball valve opening and closing switch is quick and convenient. Since the ball valve only needs to rotate the handle by 90° under normal conditions, the full opening or closing operation is completed, and the quick opening and closing is easy. It can realize fast opening and closing. The opening and closing time of some structures is only 0.05~0.1s, which can be used in the automation system of the test bench. When the valve is quickly opened and closed, the operation is shock-free. (3) Stainless steel ball valve has good sealing performance. At present, the valve seat of most ball valves is made of elastic materials such as polytetrafluoroethylene, and the sealing pair composed of metal and non-metal materials is usually called soft seal. In general, the sealing of the soft seal is easy to ensure, and the processing accuracy and surface roughness of the sealing surface are not very high. (4) Stainless steel ball valve has a long service life. Since the PTFE has good self-lubricating property, the friction and wear with the sphere is small, and the roughness is reduced due to the improvement of the sphere processing technology, thereby improving the service life of the ball valve. |
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Tunnel Spear Bolt is classified under the special type of bolts that are known as structural bolts which can be produced in various grades, sizes and load capacities depending on their specific use. These spear tunnel Bolt are utilized to make transportation through undersea and underground tunnels possible by binding together a number of metal beams and posts which make up the tunnel`s frame.
Application of Tunnel Spear Bolt
For comnecting concrete rings by casting plastic dowel in
Photos of Application of Tunnel Spear Bolt
Technical Requirement of Tunnel Spear Bolt
1.Material :grade 4.6,5.8,6.8,8.8,10.9,12.9
2. finish
Plain,Dacroment,Hot Dip Galvanized
Supply city of Tunnel Spear Bolt
Denmark,Spain,India,Italy,USA
Tunnel Spear Bolt,Rail Steel Tie,Spear Bolt With Washer,Hdg Spear Bolt
TAICANG ZHONGBO RAILWAY FASTENING CO., LTD. , https://www.railfastener.com