Cause of equipment accident
Release time：2018-08-29 Browse：392
The size of the equipment accident rate has many influencing factors and is very complicated. It is not only related to the technical level of the entire industrial field, but also related to the social culture and human quality.
Under the same conditions, the accident rate of the pressure vessel is much higher than other mechanical equipment. Originally, most pressure vessels are static and relatively stable loads. They are not as easy to fail due to excessive wear as general rotating machinery, and are not prone to fatigue failure due to high cycle repeated loads like high speed engines. The reasons are mainly the following.
1, technical conditions
1) The conditions of use are harsh. The pressure vessel not only bears different pressure loads (in general, pulsating loads) and other loads, but also runs under high temperature or deep cooling conditions. The working medium is often corrosive and the working environment is harsh. .
2) Easy to overload. The pressure inside the container often rises rapidly due to operational errors or abnormal reactions, and the container is often broken without being discovered.
3) Local stress is more complicated. For example, around the opening of the container and other structural discontinuities, fatigue cracking is often caused by excessive local stress and repeated loading and unloading.
4) There are often serious flaws hidden. Welded or wrought containers often leave serious defects such as tiny cracks in the manufacturing process. These defects can be suddenly broken if they are expanded during operation or under appropriate conditions (such as operating temperature, working medium properties, etc.).
2, use management
1) Use is not legal. Purchase some equipment produced by factories without pressure vessel manufacturing qualification as pressure equipment, and illegally use them as pressure vessels to avoid safety supervision and management such as registration, use registration and inspection, leaving endless troubles.
2) The container is legal and the management operation does not meet the requirements. The company does not have or lacks technical management personnel who understand the pressure vessel expertise and understand the national regulations and standards for pressure vessels. The pressure vessel operator does not have the necessary professional training and assessment, and is undocumented, which is very likely to cause operational accidents.
3) Pressure vessel management is in the "four no" state. That is, there is no safe operation procedure, and there is no technical file for establishing pressure vessel, three employees with no pressure vessel and relevant management personnel, and no regular inspection management. The pressure vessel and safety accessories are in an uncontrolled state of blind use and blind management.
4) Unauthorized changes and conditions of use, repair and renovation. The operator ignores the safety of the pressure vessel and changes it in order to adapt to the needs of a certain process.
The use and conditions of use of variable pressure vessels, even with "disease" operation, illegal overload and overpressure production have serious consequences.
5) The local government's safety supervision and management department and related administrative law enforcement departments are not in place. The work of the safety supervision and management department and the relevant administrative law enforcement departments failed to use the development of the socialist market economy, especially the proliferation of private and private enterprises with small scale and wide distribution, which made the safety supervision and management of pressure vessels have a blind spot and management is not in place. The phenomenon has contributed to the illegal use and violation management of pressure vessels.
