Inspection of hoisting machinery is very important. Inspectors shall inspect the hoisting machinery in strict accordance with the inspection requirements and procedures to prevent the occurrence of missed inspection and false inspection. While ensuring the life safety of relevant personnel, improve the safety of the working environment of hoisting machinery and make it better serve the urban construction.

1 overview of hoisting machinery and inspection technical requirements

Overview of 1 1 hoisting machinery

Mechanical and electrical equipment used for vertical lifting or vertical lifting and horizontal moving of heavy objects is called lifting machinery, including motors, couplings and other 1 1 components. The rated lifting capacity of the elevator is at least an elevator with rated lifting capacity greater than or equal to 0. 5t； Cranes with rated lifting weight not less than 1t and lifting height greater than or equal to 2m, electric hoists with fixed bearing form, etc.

Due to the great influence of hoisting machinery on material handling, safety and quality issues are important contents of hoisting machinery inspection. If these two tasks are not done well, it will lead to the failure of hoisting machinery, affect the construction progress, and may also cause major safety accidents of special equipment, resulting in loss of life and property. In addition, the main task of lifting machinery is to lift, load and unload and transport materials, but in the actual operation process, there is no fixed direction and path, and the nature and shape of materials loaded by lifting machinery are also different, even including inflammable and explosive dangerous goods. Coupled with uncertain factors such as external conditions, such as rugged working site, extremely harsh climatic conditions and high-intensity production load, the safety of lifting machinery is facing a severe test, which leads to a noteworthy situation. Therefore, it is necessary to conduct a comprehensive inspection of the hoisting machinery regularly, solve the problems in time, and ensure the safe production and safe use of the equipment.

1.2 technical requirements for inspection of hoisting machinery

According to different functions, there are various types of hoisting machinery, and each type of hoisting machinery and equipment has its own corresponding inspection technical requirements, but the inspection process is carried out according to the following principles: First, before the inspection of hoisting machinery, it is necessary to read and understand the corresponding inspection technical specifications and use methods that meet the inspection technology to inspect it. Secondly, it is necessary to conduct an all-round inspection of the parts in different positions of the hoisting machinery to check whether different types of parts are damaged and whether their functions are effective. There are many and complicated parts of hoisting machinery and equipment, including electromagnets, hooks, suction cups, container spreaders, high-strength screws, chains, wire rope sleeves, pulleys, drums, braking devices, gears, anchor chains, wheels and safety hooks. Secondly, the welding clearance of the main mechanical parts of the crane is also the focus of inspection. Take the welding gap as an example, especially the welding of the joint parts of the main beam cover plate, web plate and flange plate, to avoid cracking and other problems. Once there is a problem, it is necessary to inform the relevant technical personnel in time and solve it in time. Wear and consumption of parts and components used for a long time under the action of friction, such as wire ropes, lifting tools, pulleys, gears, etc. , but also in accordance with strict standards for inspection; The welding gap between spare parts and special spare parts shall be inspected according to the corresponding inspection standards and methods.

2 problems existing in the inspection of hoisting machinery

2.2 Mismatch between Buffer and Stop Device

Under normal circumstances, the crane manufacturer has installed the bumper at the appropriate position of the crane end beam in the production process, and the user only needs to weld and install the bumper when receiving the goods. However, in order to pursue economic benefits, most manufacturers only weld an ordinary iron plate on the rail surface at the end of the track to replace the stopper device. This kind of limit device which has not been checked by the standard design strength can not only realize the close cooperation between the collision plate and the bumper, but also easily collide with the wheel. When the collision range is large, it will have a huge impact on the wheel, leading to the deformation of the wheel and shortening the service life. In actual operation, gnawing at the track may lead to serious derailment accidents.

2. The plug is broken

There are two kinds of limiters: travel limiter and rising limiter, which are very important safety devices for lifting machinery. With the gradual increase of working hours of hoisting machinery, the wear degree of brake pads will become more and more serious. With the aging and excessive braking clearance, any of these problems will affect the braking of the control mechanism and lead to its looseness, which will eventually lead to a larger braking distance, which will impact the travel limiter, lead to the failure of the travel limiter and lead to an over-travel accident. In addition, the speed is too high when hitting the upper limit due to careless operation of human factors, and the problem of oblique hanging occurs due to improper operation, which leads to the change of the movement path of the wire rope, which is pulled obliquely, and the wire rope is easy to wind and trip, eventually leading to the failure of the crane limiter. Finally, the braking of crane truck is too tight, which will lead to problems such as wire rope and limit screw, and it is also easy to cause safety accidents of crane. In the actual inspection process, inspectors often tend to ignore the inspection of the limiter, laying a hidden danger for the accident.

2.3 Wire problem

Under normal circumstances, lifting machinery must be controlled by multiple lines to complete the operation, so the quality inspection of electrical lines is also a top priority. However, due to the complex site conditions. It is difficult to find out whether the electrical circuit conforms to the national regulations and whether the electrical circuit is aging.

3 Measures to solve the problem of hoisting machinery

First of all, under the existing management system and related systems in China, gradually changing the monopoly position of crane inspection, introducing competition mechanism, and vigorously supporting the opening of crane inspection market will increase the market competition of crane inspection under the action of competition mechanism, and inspection institutions will inevitably improve the inspection quality in order to find a way out; Secondly, it is necessary to strictly establish and improve the market access system for lifting machinery inspection. Institutions and companies that do not meet the standards are resolutely not allowed to enter the market. The quality supervision department should also change the traditional concept, improve the service consciousness, facilitate the people and improve the service strength and level of the quality supervision department, take the initiative to accept the supervision of the higher authorities and cooperate with the management of relevant departments. In the process of inspection, the inspection organization must report the results to the relevant departments in time once it finds unqualified lifting machinery and equipment, and the unqualified items must be comprehensive and accurate. Secondly, the supervision department should do a good job of supervision: make the installation unit install the hoisting machinery in strict accordance with the requirements of the installation specification, go through the notification procedures in the relevant departments in time, and go through the inspection procedures in the inspection agency in time after the hoisting machinery is installed. After receiving the application from the installation unit, the inspection institution shall inspect the hoisting machinery as soon as possible according to the actual situation. After the inspection, the inspection report shall be issued in time, and the inspection results and existing problems shall be reported to the relevant supervision departments. If there are problems with hoisting machinery, the relevant regulatory authorities should promptly urge the relevant units to carry out rectification. Third, improve the inspection level of inspectors to ensure that the inspection of each lifting machinery and equipment can be effectively standardized. Fourth, establish relevant systems to encourage enterprises to carry out installation inspection. The construction unit shall carry out the installation in strict accordance with the installation specifications. In the process of inspection, not only should each crane be inspected in a standardized way, but also all components should be inspected comprehensively and carefully to avoid safety accidents caused by negligence in inspection. Through the inspection of hoisting machinery, the existing problems can be found in time to avoid the occurrence of safety accidents of hoisting machinery, which has a guiding role in improving the safe use of hoisting machinery.

4 conclusion

In the process of modernization, hoisting machinery plays an important role in promoting economic construction. While playing its role, there are also many security risks. Only when installation enterprises enhance their safety awareness, hoisting machinery inspection institutions standardize inspection work, improve inspection ability and level, and supervision institutions strengthen supervision and management can hidden dangers be fundamentally discovered and eliminated. At the same time, it is more important to respect everyone's life and make a modest contribution to maintaining social stability.

;