The significance of regular inspection and prevention of damage to pressure vessels of chemical equipment is to find out existing and potential equipment defects and hidden dangers in time, as well as the safety status of vessels. At the same time, eliminate and monitor various dangerous factors while reducing the accident probability of pressure vessels of chemical equipment, and promoting the safe operation of pressure vessels.
1. Preventing fatigue damage
Fatigue damage is typical pressure vessel damage. The measures to prevent fatigue damage are to avoid long-term overload operation of industrial equipment pressure vessels. Due to the limitation of the acting force borne by industrial pressure vessels, it is necessary to reduce the pressurization of the vessels appropriately, so as to control the possibility of damage of the pressure vessels.
2. Preventing ductile deformation and brittle damage
According to the actual operation conditions, the strength materials prepared by the container should be reasonably selected to avoid ductile deformation and brittle failure. For industrial pressure vessels with deformation, unless it is a slight local depression, other deformations need to stop the continued use of the vessel. After the industrial pressure vessel is deformed, the thickness of the vessel will become thinner, and the corrosion resistance and toughness of the deformed material will be weakened accordingly. For industrial equipment and pressure vessels with slight bulging in small areas, little influence on other parts and good weldability of container materials, after the bulging parts are dug out, repair welding plates of the same material and shape, and the weld quality can be checked at the same time.
3. Preventing corrosive damage
When manufacturing industrial equipment pressure vessels, it is recommended to choose high-quality metal materials to reduce the content of impurities in the body, so as to ensure that the corrosion resistance of industrial equipment pressure vessels can reach the standard. Before the pressure vessel is put into use, chemical enterprises suggest installing barrier materials in the vessel wall to avoid direct contact with corrosive chemicals. Clean up in time after use, do a good job in inspection and maintenance of industrial equipment and pressure vessels, and find and replace cracked pressure vessels in time. Starting from the analysis of anti-corrosion operation, it can effectively solve the surface corrosion of pressure vessels of industrial equipment. Surface anti-corrosion mainly consists of two schemes: surface sandblasting and surface spraying. Before surface anti-corrosion operation, pretreatment operations such as removing rust and oxide on surface steel by the sandblasting machine are needed to ensure that the surface is clean and free of foreign matters, and then preservatives are reasonably blended and the blending ratio is strictly controlled. Anti-corrosion operation steps and methods should be carried out in strict accordance with national standards.
4. Preventing creep
The creep of pressure vessels is mainly influenced by a high-temperature environment and stress. Therefore, in order to effectively solve the creep rupture, it is necessary to avoid the stress and high-temperature conditions in the container at the same time. In order to avoid the influencing factors of creep, regular inspection and maintenance are first needed. Secondly, replace the damaged industrial equipment and pressure vessels in time to avoid the gradual expansion of creep problems. Finally, strengthen the control of the quality of industrial equipment pressure vessels, formulate a perfect procurement plan for industrial equipment pressure vessels, and introduce high-quality industrial equipment pressure vessels to reduce the incidence of safety accidents and prolong the service life of industrial equipment pressure vessels.
Quality control of pressure vessel damage
1. Quality inspection before manufacturing
First, strictly examine the construction drawings. The drawing is the technical reference and important basis for the pressure vessel to be put into production. Therefore, we should strengthen the examination of the design drawings of industrial equipment and pressure vessels to ensure that they meet the current specifications, manufacturing standards and manufacturing conditions. Secondly, focus on the reasonable preparation of processing technology. The production process and manufacturing process of pressure vessels should be strictly based on the corresponding technological process, to unify the processing technology of pressure vessels in batch production, so as to improve the production efficiency and promote the orderly implementation of the processing flow. Containers with new technologies, new processes and new materials should be used to make a reasonable technological process around processing requirements. Finally, strengthen the quality inspection of raw materials. It is required that the materials selected for process equipment and pressure vessels meet the standards and meet the requirements of processing technology and production conditions. Enterprises should improve the supervision system as soon as possible, and strengthen the centralized supervision of the quality of chemical equipment, pressure vessels and materials.
2. Controlling the welding quality
Firstly, the quality control of welding materials should be paid attention to. There are many management and control links of welding materials, involving control points such as procurement, acceptance, reinspection, drying and distribution. Welding materials shall be selected strictly according to the requirements of pressure vessel materials, and the quality of welding materials shall meet the relevant provisions of industry standards and national standards. Secondly, starting with the analysis of welding process control, welders are required to have welder qualification certificates and be able to carry out welding work with ease. They can strictly follow the welding procedure book or welding procedure card. Before welding the pressure vessel, make a reasonable welding process plan, which involves the selection of the groove form and the welding method, welding materials, nondestructive testing, etc. In order to ensure the implementation of the process and the quality of the weld seam, the responsible engineer is required to strengthen the supervision of the implementation and strictly control the welding sequence, preheating before welding and welding material selection. Strengthen weld inspection, including nondestructive flaw detection and appearance inspection, and introduce advanced flaw detection methods and technical equipment based on the principle of bringing in and going out, so as to avoid misjudgment and to improve the overall quality of industrial equipment and pressure vessels.
3. Strengthen the quality control of equipment
The potential safety problems of pressure vessels in production and put into use can not be ignored. Chemical pressure vessels are dangerous equipment. It is necessary to strengthen the quality control of vessels. The concept, formulation and measures of quality control should run through every link of vessel use. Before establishing the quality control system, widely collect the opinions and ideas of the staff, so as to make the quality control closer to the actual situation of the application of chemical equipment and pressure vessels. In order to improve the effectiveness of quality control, establish a perfect self-inspection process and mutual inspection procedure, introducing modern management means such as refinement and process management. Timely discover and deal with the damage factors such as cracks in chemical equipment and pressure vessels. Chemical enterprises need to strengthen the concept of preventing pressure vessel accidents and establish a perfect monitoring and use system according to the use of pressure vessels of chemical equipment, and then minimize the possibility of vessel accidents. According to the quality problems found in the monitoring, take targeted measures for maintenance and treatment, and realize the integration, optimization and efficient utilization of resources.
4. Providing talents
Chemical enterprises should strengthen and improve the personnel training and assessment mechanism, and require staff to have a deep understanding of the operating principle, structural system and technical parameters of chemical equipment and pressure vessels, so as to separate them from the traditional working modes, attitudes and concepts, and pay more attention to the safe operation of chemical equipment and pressure vessels. Furthermore, they should assist in monitoring the use of pressure vessels of chemical equipment, find and deal with various quality problems in time, and offer suggestions for improving the management scheme of the damage of pressure vessels. In particular, the inspectors and testers of the safety status of pressure vessels need to know the contents of Regulations on Safety and Technical Supervision of Pressure Vessels and other laws and regulations, regularly inspecting pressure vessels and mastering the methods of hydrostatic test, internal and external inspection and external inspection.
5. Systematic monitoring of risk factors
It is important to improve the information literacy of the staff, and their flexible operation on the inspection system. Set up a database, and sort out the destruction forms and causes, dangerous factors and treatment of pressure vessels in operation into the database, which lays a foundation for information technology to intelligently and automatically monitor the quality problems such as the destruction and safety accidents of pressure vessels. For example, pay attention to the causes of damage to pressure vessel parts, or fatigue cracks caused by thermal stress and alternating temperature; cracks or plastic deformation of parts due to high temperature creep; low cycle fatigue damage and low cycle fatigue crack caused by pressure fluctuation or frequent pressure relief; long-term high temperature leading to the deterioration of steel structure, including hot embrittlement, graphitization and pearlite spheroidization, which gradually weakens the mechanical properties of steel. The inspectors sorted out and put the risk factors of these parts into the database, which provided a valuable reference for the subsequent prevention work of chemical equipment and pressure vessels damage, and promoted the quality control and prevention scheme to be more targeted, effective and feasible, putting forward higher requirements for the professional quality and professional ability of the staff.
In the chemical industry, the harm and influence of malignant accidents of industrial equipment and pressure vessels can not be ignored. Workers are required to enhance their awareness of the use of pressure vessels; strictly follow the specified requirements; strengthen the control of sealing quality and risk factors of vessel rupture, and at the same time improve the production technology and management level of vessels to ensure safety performance and effectively prevent the occurrence of pressure vessel rupture.