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Welding quality plays a crucial role in pressure vessels; it can be said that welding, to some extent, determines the quality, reliability, cost, and production efficiency of pressure vessels. Welding of pressure vessels is a crucial part of the manufacturing process for such vessels. The service life and performance of pressure vessels depend to a large extent on the quality of the welding; therefore, it is essential to address any issues that arise during welding promptly and to strictly control the quality of welding in pressure vessels. Welding equipment: The quality of welding equipment is also a guarantee of the quality of the welds. If there are defects in the welding equipment, then the welds produced by that equipment will most likely have defects as well. To this end, it is necessary to strengthen the maintenance and management of welding equipment in order to improve its quality. Currently, welding equipment mainly includes electrode drying ovens, welding machines, heaters, temperature meters, clamp ammeters, insulation tanks, etc. The electrode drying ovens are equipped with temperature meters, while welding machines are fitted with voltage meters and ammeters. Managers must regularly inspect welding equipment such as electrode drying ovens and welding machines to ensure that the temperature meters, voltage meters, and ammeters function properly and display accurate readings, thus guaranteeing that the process parameters in welding operations are entirely correct. After each inspection, the welding equipment must be maintained to ensure it operates properly; it is essential to avoid operating the welding equipment when it is damaged. After each inspection and maintenance task, records must be made promptly and archived for future reference. Welding materials: The management of welding materials primarily involves aspects such as material procurement, material inspection, material storage, material drying, material distribution, and recycling. In the process of purchasing materials, it is first necessary to assess various aspects such as the qualifications of the manufacturing enterprise, the quality of its products, and its reputation. Once a suitable company has been identified, business negotiations are carried out with it, and relevant purchase contracts are signed. After the welding materials are purchased, inspectors must strictly inspect them in accordance with the purchase contract, material quality certificates, technical specifications for ordering, and other relevant standards. For materials with incomplete quality certification documents, missing items, questionable performance indicators, or special technical requirements, re-inspection is required; those that fail the inspection will be rejected outright. After the materials pass the inspection, the inspector must affix a approval stamp to them before they are stored. Once stored, the warehouse staff shall organize them according to standards such as type, grade, specifications, and batch number. The materials must be stored in a well-ventilated and dry warehouse; corrosive substances and harmful gases are not allowed to be present there to prevent corrosion of the materials. The materials should be placed on shelves, at a distance of at least 300 mm from the floor and walls. The indoor temperature must be above 5°C, and the relative humidity must be above 60%. Before use, the welding rod must be dried according to the temperature standards specified by the manufacturer. Inside the insulated container, the welding rod should be stored for no more than 4 hours; if that time exceeds 4 hours, it must be dried again before use. Before starting work, welders must obtain the welding materials in accordance with the welding procedure specification sheet. Managers must carefully review this sheet, distribute the materials strictly in line with it, and keep records of the materials issued. Welding inspection is an important aspect in ensuring the welding quality of pressure vessels. Its main components include pre-welding inspections, checks on the adherence to welding procedures, post-welding visual inspections, and non-destructive testing of welds. Before welding, inspections are primarily carried out on the welder’s qualifications, welding materials, weld cleaning, weld preparation, preheating temperature, and other related aspects. During welding, it is important to closely monitor whether the welder is able to carry out the welding in accordance with the specified welding procedures. After welding, the welds must be inspected, and non-destructive testing of the welds should be carried out. During the weld inspection, careful examination of the weld and the heat-affected zone is required to ensure that their surfaces are free from pores, pits, cracks, incomplete welding, inclusions, or spatter. For welds that require post-heating treatment, it must be carried out immediately after welding, and the temperature must be selected in strict accordance with the relevant specifications in the process documents; a time period of 0.5 hours to 1 hour is appropriate. Immediately after welding, the weld area should be heated and kept at a constant temperature to facilitate the rapid diffusion of hydrogen ions present in the weld, thereby improving its crack resistance. Non-destructive testing of welds must be carried out strictly in accordance with relevant technical operating specifications, and any testing that does not follow these specifications must be avoided. Welding environment: The welding environment has a significant impact on the quality of welding. During the welding process, it is necessary to manage the welding environment in strict accordance with relevant regulations. Welding operations must be stopped if the environment presents the following conditions and no effective protective measures are in place: when the ambient temperature is below -5°C, during rainy or snowy weather, when the relative humidity is greater than 90%, or when the wind speed is greater than 2 m/s during gas shielded welding, and greater than 8 m/s during manual welding.