Coal mill maintenance, steam turbine operation start-up cranking 1. Purpose of the cranking device Steam turbine operation cranking is an important rotating equipment to ensure uniform heating and cooling of the steam turbine rotor during startup and shutdown of the steam turbine unit. Cranking not only enables the unit to be started at any time, but also can be used to check whether the steam turbine unit has normal working conditions, such as: whether there is friction in the dynamic and static parts, whether the curvature of the main shaft is too large, whether the lubricating oil system is working normally, etc. 2. Characteristics of the cranking device. The turbine cranking of the cranking device can realize automatic operation and program start. The cranking speed can be divided into minutes. The motor power is equipped with a cranking control box and has automatic operation, manual operation and inching. Three functions. There is no sticky material stuck when put into operation, and it can be effective and automatic for a long time without oil leakage. There is no tooth tip collision causing mechanical damage. The electromagnetic clutch can automatically disengage and reach the position easily. 3. Structure of the cranking device The cranking operation of the steam turbine is mainly composed of two parts: the worm gear, the transmission ratio of the worm reduction device and the electromagnetic clutch. The combination of a reduction motor and an electromagnetic clutch is used to replace the oil cylinder. The working torque is the same, and the action of the connecting rod system is transmitted through belt transmission. It is indeed ideal whether it is factory testing or power plant operation. The clutch includes main components such as sliders, pawls, spiral internal gears, external gears and buffers.
Coal Mill Maintenance Application No. Patent No.: A medium-speed wheel-type coal mill grinding roller maintenance and pull-out device to overcome the existing disassembly parts or problems existing in the coal mill maintenance process. The deformation of the access door affects the normal operation of the coal mill. It consists of a fixed frame fixed on the outer surface of the lower part of the casing, a movable frame installed on the fixed frame with a vertical slide mechanism, a lifting cylinder hinged between the fixed frame and the movable frame, and a cylinder that can be turned vertically to extend into and out of the casing. The turning frame, the turning cylinder with its lower end hinged on the movable frame, the turning connecting rod hinged between the upper end of the turning cylinder and the turning frame, the grinding roller installation fixed plate on the turning frame, the oil pipeline and oil flow connecting the oil cylinder and the pump station Composed of electrical control unit. The positive effects of this utility model are: it eliminates the shortcomings of increased workload, large amounts of consumables, and long construction period caused by the need to disassemble the upper half of the coal mill during maintenance in the past, or the door body of the inspection door that carries the grinding roller to rotate out. The deformation of the body and door causes the grinding roller to move out, the loading is not smooth, and the door is not closed tightly, resulting in the leakage of pulverized coal