Cycle of repair and maintenance of a cutter suction dredger

Planned and pre-repaired cutter suction dredgers not only prevent problems from occurring, but also save maintenance time, which contributes to increased dredger utilization and economic benefits. However, its superiority is largely due to the actual repair selection. As an indicator, the traditional selection principle is based on the effective use time of dredger machinery. When the dredger machinery reaches the end of its useful life, it will be repaired as part of preventive maintenance. As a result, determining the repair cycle becomes the primary concern.

1. Different types of repair work

Repairs are traditionally divided into three categories based on the lifetime, repair workload, and construction period of dredger equipment: minor repairs, medium repairs, and major repairs.

(1) minor fix

The first stage of transition from maintenance to repair is minor repair of dredger mechanical equipment (composition: driving device, transmission device, etc.). It is formulated for some problems that cannot be resolved during shift handover, based on records of equipment defects discovered during daily maintenance inspections. Make a plan for minor repairs. Repair items include defects that can be repaired within the time frame specified in the minor repair plan, replacement parts, lubricating grease, clearance adjustment, and so on. Furthermore, some more complex inspection items should be included. Minor repairs are becoming more common. The monthly minor repair time can be used however you see fit, as long as it does not exceed the original minor repair budget. For example, the original minor repair schedule was three times per month, with a total repair time of 32 hours. Despite the fact that the total repair time did not exceed 32 hours, some difficult and time-consuming repair items could be handled in the 16 hour minor repair, which is a favorable arrangement. Minor repairs are only a means of maintaining simple reproduction due to the short planning time for minor repairs. Minor repairs shall be included in the current month's production cost from the production cost.

(2) Moderate repair

Some dredger equipment defects and hidden dangers that take a long time to deal with may not be resolved within the minor repair time due to the short repair time of dredger mechanical equipment (composition: driving device, transmission device, etc.). It cannot, however, be postponed until the next overhaul, so one or more intermediate repairs must be scheduled between the two overhauls. The scope of intermediate repairs is relatively broad, with many items that are primarily restorative in nature.

(3) Overhaul

After a long period of use of the dredger equipment, some key parts (such as the foundation of the main equipment, the crane track, the main motor, the blast furnace shell, etc.) are damaged and cannot be repaired in a short time, so a longer shutdown time must be arranged Repairs are called overhauls. According to production practice experience and relevant statistical data, the overhaul period of a certain major production equipment under normal conditions can be estimated, and the length of the overhaul period depends on the quality of the overhaul work of dredger equipment maintenance. The key issues are: one is to use the equipment in accordance with the regulations, and the equipment must not be overloaded; the other is to ensure the quality of overhaul construction.