Swivel packing seal assembly is the key of the swivel, whose function directly influences its service life, further more, and affects the drilling speed.

The wash pipe packing of drilling swivel showed wear-and-tear continually in drilling process due to its structural design.

The mean value of work loads on a shaft bearing of swivel and rotary table is determined by basic principles of fuzzy theory, considering the loads' fuzziness and the requirement for reliability.

Effects of Cast Iron and Chromeplate Tap on Over Night Tap Water Quality;

Human-computer interaction problem of tap was discussed from the two aspects: switch device design and flowing angle design.

The calculation method of the firm power of cascaded hydropower stations system is described in brief not considering up-downriver stations runoff compensation, and this paper puts forward the general calculation method of the firm power of main-reservoir cascaded hydropower stations based on runoff compensation.