跳至主要内容

Electric hoist hook introduction

The hook is an important part of the chain electric hoist, it not only bear the weight of the object, but also bear the impact load of rise and braking, so the hook material mechanical should have high strength and impact toughness. The commonly used hook according to the manufacturing process can be divided into forging hook and plate hook. The forging hook generally forged by 20SiMn, 36Mn2Si and other steel, while plate hook is forged by the multiple pieces of steel plate riveted joint, generally use 20# steel, 16Mn steel. The plate hook is convenient to manufacture, and the load can be uniformly distributed on each steel plate, and the fracture can not happen at the same time, so the reliability of the work is higher than the forging hook. Hook once broken in use process, can cause accidents. Therefore in use must pay attention to check, use a magnifying glass check whether there are cracks. Once found crack, immediately stop using.
The hook dangerous section is the section of maximum bending stress.
The maximum bending moment at the point, and often appear groove cause to the friction of the wire rope, when the wear of the dangerous section reaches 10% of the original height, should be scrapped immediately. It is absolutely not allowed to continue to use after rewelding.
Hooks must be strict inspection before delivery, and loading capacity shall be all above the nameplate, can not use if there is no capacity mark, until it is calculated, determined the safety of the weight, and do the load test which load is 1.25 times the benchmark, no permanent deformation and crack phenomenon in the test. For the hook which is used regularly, should always check whether there is permanent deformation and wear. The hook should be equipped with a safety device to prevent unhooking.

评论

此博客中的热门博文

How to deal with 3 ton electric chain hoist motor overheating

Any machine has the cycle and time of operation, is not suitable for a long time continuous operation. Long time operation will cause mechanical damage and even accidents, but in general if the 3 ton electric chain hoist surface temperature is too high, we need to check what is the reason. Firstly to check whether it is because the electric hoist weight is too large, beyond the 3 ton electric chain hoist rated weight. Overweight operation will make the motor over heating, overload for a long time will cause irreparable damage to the electric chain hoists for sale.  Electric hoist motor  is not overloaded, but still heating, should check whether the motor bearing damaged; Should also check whether the motor Work according to regulations, which is one of the reasons causing the motor heating. When the electric hoist motor is running, brake clearance is too small, not completely disengaged, causing great friction, while the frictional heating is also equivalent to the additional load

The reason of electrical wire rope hoist does not work after starting

Mainly because of the hoist does not reach to the rated operating voltage, there are generally 3 kinds of situations: 1.Find out whether the power supply system supply power to wire rope electric hoist , generally used test pencil, such as no power supply; 2.The main control circuit of the wire rope electric hoist is damaged, the line is broken or the contact is bad, can also let the hoist motor not be electrified. This situation, need to overhaul the main control circuit. When maintenance, in order to prevent missing phase to burn the motor casused by the main control circuit supply power to three-phase motor, or hoist motor suddenly operate and cause danger, must disconnect electrical wire rope hoist motor from the power supply, only supply power to the main control circuit. Then start and stop switch, check and analyze the working condition of the electric appliance and the line, repair or replace the failed electric appliance or line. When the main control circuit is confirmed

Working level of overhead gantry crane

Overhead gantry crane  installation site and the work conditions is vary greatly, the use of lifting capacity and working frequency are also different. In order to use the crane economically and reasonably, it is necessary to choose the appropriate working level according to the working condition of the crane. The working level of the bridge crane is divided into A1 ~ A8, according to the level of the crane and the load state, that is, according to the frequency and load degree of the crane through the calculation to determine. The crane has a certain number of working cycles during its useful life. A working cycle of a  travelling gantry crane  is to start the process of loading the goods from the beginning to the next. The total number of working cycles represent the utilization of cranes. In order to facilitate the calculation, the total number of working cycles can be divided into 10 categories. 200-400 ton heavy duty travelling  overhead gantry crane for sale