By comparison and analysis of O-type ball valve and direct single seat quick opening valve,the new concept of using direct single seat quick opening valve in substitution of O-type ball valve is given;on the other hand,the calculation and choice of model of direct single seat quick opening valve are elaborated.

In-situ turning repair technique for safety valve seats in power plants;

Development of valve seat for CNG engines and the valve test for matching;

Cause for damage to pre-start valve seat of CB25-91/10/1.2 steam turbine regulator valve;

Analysis and repair of crack on intercept valve base oflarge imported steam turbine;

The processing technology for the valve base is introduced and the forging process is analyzed.

The results show that,as the emulsion enters into the lubricating oil,gap corrosion will be generated on the surface of the valve base,which makes the mating surface peeled off and the gap increased.

Machining methods for thin walled support ring seat;

The text introduces the structure features,characteristic parameters and workingprinciple of a new type of Inlet Ball Valves for Water Turbo,discussing and analysing ahydraulic relay to open the ball valve and a weightily hammer to close the ball valve,andthe structure of a single eccentric valve seat that can balance the pressure difference betweenthe inlet and outlet of the ball valve.