② The friction between the valve stem and the packing is relatively small, which reduces the resistance of the valve action, and the wear of the valve stem and the packing is also small, thus prolonging the service life. In addition, the valve stem with smaller diameter has little change in thermal expansion and cold contraction at medium and high temperature, which avoids the situation that the friction between the valve stem and the packing increases or adheres to each other at medium and high temperature.
(3) Because the new sleeve valve is a balanced structure, compared with the unbalanced straight-through single-seat valve, the actuator can be smaller, but it can overcome the higher medium pressure difference than the straight-through single-seat regulating valve. For example, the new sleeve control valve DN200/ DN250/ DN300 only needs C60 cylinder actuator, and does not need a larger cylinder actuator. At the maximum valve seat diameter, the allowable working pressure difference is about 2 times that of the same straight-through single-seat regulating valve, and membrane actuator and explosion-proof electric actuator can also be equipped.
(4) The new sleeve regulating valve adopts self-centering and threadless clamping seat structure and modular design, which makes the valve easy to disassemble and assemble, and can reach the leakage standard of more than four levels.
⑤ When the temperature is lower than 150℃, the metal hard seal can reach the leakage standard above grade 4, and the PTFE soft seal can reach the leakage standard above grade 6. The service life of the new sleeve regulating valve DN200/ DN250/ DN300 is longer than that of the straight-through single-seat regulating valve.
⑥ When the new sleeve regulating valve is above DN80, the geometric size and tolerance of the regulating range shall meet the requirements of the drawings.