Tower crane is a commonly used lifting equipment on construction sites, also known as" Tower Crane”, Lengthened section by section, used to hoist construction materials such as steel bars, wooden beams, concrete, and steel pipes. Tower cranes are an essential equipment on construction sites, but accidents often occur

In construction, tower cranes are usually used as equipment, which can lift things on the ground to high places, making it very convenient! However, when using a tower crane, its danger is also high, and sometimes tower crane collapse accidents may occur. Let's take a specific look at the causes of tower crane accidents

1、 Installation and disassembly issues

1. The installation and disassembly team is unqualified and has no certificate to undertake disassembly and assembly tasks. The personnel, equipment, technology, and other aspects of the installation and disassembly unit do not meet the requirements, which is an important cause of the accident

2. There is no plan for installation and disassembly, and no safety technical disclosure, relying on experience. The direct cause of the accident is that the dismantling unit does not prepare a dismantling plan, does not provide safety technical disclosure, and acts recklessly based on experience and violation of regulations

3. Violation of disassembly and assembly procedures during installation and disassembly construction. During the disassembly and assembly process, the dismantling unit does not follow the sequence of disassembly and assembly in the tower crane user manual, and does not operate according to the disassembly and assembly plan and safety technical disclosure requirements, which saves time and relies on imagination

4. Do not apply for disassembly and acceptance procedures. The unit using the tower crane and the dismantling unit did not handle the dismantling application and acceptance procedures according to regulations, and lost the opportunity for the government's competent department to check

2、 Usage issues:

1. Operators and commanders are employed without a certificate. The tower crane driver and commander did not receive professional training and obtain qualification certificates as required, and did not possess corresponding professional skills and knowledge

2. Operations and command personnel operate in violation of regulations, and command in violation of regulations. For example, overloading lifting, inclined lifting, and using a tower crane to lift the concrete pump delivery pipe at the construction site and rotate it freely

3. Insufficient daily inspection and maintenance of equipment by operators has resulted in mechanical safety hazards for the tower crane. If there is insufficient understanding of the performance of the torque limiter of the tower crane, and it is unclear whether it truly works, it may lead to accidents due to the mistaken belief that it is working normally in the event of its failure. Neglecting human factors, such as the range and weight that can be lifted, leaving a bottomless or unclear mind

4. Insufficient education and training for operation and command personnel. Many units only provide pre job training and neglect continuous training and improvement of operational skills and safety awareness for operators, as well as continuous training for command personnel

3、 Quality issues with tower crane products themselves:

1. Design issues. The design of the torque limiter has defects and poor sensitivity; Unreasonable stress in steel structure design, defects in hydraulic system design, etc

2. Problem with spare parts. The quality issue of the torque limiter component is related to the steel material used in the steel structure; Quality issues with hydraulic system components, etc

3. Manufacturing issues

3.1. Steel structure welding does not meet the requirements. The height of the weld seam is not sufficient, and there are defects such as pores, slag inclusions, and even virtual welding, especially welding quality issues in important connection parts such as tower caps, large arms, and balance arms

3.2. The geometric dimensions of the steel structure do not meet the requirements. The cutting did not meet the requirements, and the cross-sectional size of the steel did not meet the national standard requirements

4. If there is no factory certificate or user manual, it is considered a counterfeit or inferior product. There is no batch description and no indication of changes to the original design