This paper expounds the significance of the rope creep protection, introduces the traditional method for realizing the rope creep protection, analyzes the problems existing in the rope creep protection by using the position switch, and puts forward some methods for realizing the rope creep protection of the winch by using the counting/comparing function of the PLC.

Aiming at the serious casing corrosion of water injection wells,one chemical agent is injected into the annular space of the tubing and casing,and forms a ring-shape elastical seal plug,then the suitable corrosion control agent and bactericidal agent are injected,used as a casing protection fluid.

With regard to the frequent occurrence of abnormal tripping faults of ZKH-3 feeder assembly protection in substation, implements the site-inspection, test and theoretical analysis of the faults, defines the reasons causing the incorrect operation and over-zone tripping of the assembly protection and points out the effective counter-measures.