The paper briefly introduces the use and layout of the discharge tunnel of Hongjiadu Hydropower Station, pays attention to some key design problems such as water seal type of work redial gate of the discharge tunnel, gate slot shape type, gate structure and etc.

The technology of precision roll forging by closed die groove of machine driven plough share are researched systematically.

An analysis is made of the Performance of the channel pass system while used in ■ 650 rolling mills for the trial production of flat - bulb steel for ship use, with the conclusion that this system can bring about a steady rolling down and top - quality rolled pieces.