Thus,electric submersible pump will run in a row,the damage on unit and cable causing by starting-stopping frequently will be avoided,and the goal of energy-saving and prolonging pump detection period are achieved.

Based on this analysis, five systems of quality guarantee have been established in order to extend the oil well pump detection period.

One of the main reasons of the shorter pump detection period and rework operation was that sand washing could not carry the sand to the ground during the pump detection period.

By adopting the orthogonal test method the influencing regularity was revealed on the checking period of pump affected by mainly the man-made controlling factors that effect the off-center wearing on well tube and rod of water driven oil sucker.

This paper presents the rule of the main controlling influencing factors of water drive off-center wearing and parting of sucker rod and tubing in pumping well to check period with the orthogonal test method,then finds which is the most important,establishes the best process condition unit.

By analyzing the maintenance period about full-mechanized face equipment,the decision-making model of optimum maintenance period about full-mechanized face equipment has been put forward.

Based on a study on coal mine manufacturing equipment failure character and failure density function and failure function,this paper makes an analysis of the reliability and proposes calculation methods to work out the reliability,maintainability,applicability,frequency of failure and overhaul cycle of coal mine manufactureing equipment.

Based on regular maintenance of equipments,optimization of operating conditions,combination of traditional maintenance mode and condition-based maintenance mode as well as the configuration optimization of spare parts etc,the maintenance strategies to prolong the overhaul cycle of gas turbine are described.