Automatic vertical seam welding used for the first time in domestic LNG tank construction

It is understood that in domestic LNG storage tank construction, particularly for the welding of large numbers of 9NI steel inner tanks, it is a common practice in similar projects both domestically and internationally to use automatic welding for circumferential seams and manual welding for vertical seams. However, manual welding has the disadvantages of a poor working environment, low work efficiency, and unstable welding quality. To effectively address this issue, China Global has made the automatic welding of the vertical seams in the storage tanks at the Tangshan LNG receiving station’s emergency peak-shaving support project team a key focus for research and development. The project department is responsible for the organization and practical implementation of the project, and promptly established a project team composed of relevant personnel from CNPC Jingtang LNG Co., Ltd., Beijing Huanyu Company, Beijing Xingyou Project Management Company, and Huanyu No. 6 Construction Company.

The relevant person in charge of the project team stated that, based on tasks such as current situation analysis and research, feasibility analysis and decision-making, selection of welding equipment and materials, process testing and evaluation, as well as project implementation and assessment, the team conducted a thorough evaluation of welding technologies and equipment. They also organized well-known domestic and international welder manufacturers to compare automatic butt welders, and through on-site operations, they assessed these machines in terms of welding quality, welding efficiency, and operability. Ultimately, the appropriate welders and welding materials for the site’s needs were selected, five welding process evaluations were carried out, and welding procedure manuals that met the requirements of on-site construction were prepared.

After comparing the application of automatic welding technology with manual vertical seam welding for other tanks in the same project, the technical staff in the project department found that the welding environment improved significantly, the labor intensity associated with welding was greatly reduced, the appearance of the welds was excellent, the pass rate for radiographic inspection of the welds reached 98.3%, the welding efficiency for single-sided welds increased by over 200%, the welding efficiency for double-sided welds increased by over 100%, and welding costs were reduced by 30%. 　　Through the joint efforts of all the entities involved in the project, the emergency peak-shaving support project for the Tangshan LNG receiving station has developed a set of standard automated welding operation management methods for the vertical seam welding of 9NI steel inner tanks, covering aspects such as equipment selection, welding process formulation, and welding process management. This has laid the foundation for the widespread adoption of automated vertical seam welding technology.

It is understood that in domestic LNG storage tank construction, particularly for the welding of large numbers of 9NI steel inner tanks, it is a common practice in similar projects both domestically and internationally to use automatic welding for circumferential seams and manual welding for vertical seams. However, manual welding has the disadvantages of a poor working environment, low work efficiency, and unstable welding quality. To effectively address this issue, China Global has made the automatic welding of the vertical seams in the storage tanks at the Tangshan LNG receiving station’s emergency peak-shaving support project team a key focus for research and development. The project department is responsible for the organization and practical implementation of the project, and promptly established a project team composed of relevant personnel from CNPC Jingtang LNG Co., Ltd., Beijing Huanyu Company, Beijing Xingyou Project Management Company, and Huanyu No. 6 Construction Company. 　　The relevant person in charge of the project team stated that, based on tasks such as current situation analysis and research, feasibility analysis and decision-making, selection of welding equipment and materials, process testing and evaluation, as well as project implementation and assessment, the team conducted a thorough evaluation of welding technologies and equipment. They also organized well-known domestic and international welder manufacturers to compare automatic butt welders, and through on-site operations, they assessed these machines in terms of welding quality, welding efficiency, and operability. Ultimately, the appropriate welders and welding materials for the site’s needs were selected, five welding process evaluations were carried out, and welding procedure manuals that met the requirements of on-site construction were prepared.

It is understood that in domestic LNG storage tank construction, particularly for the welding of large numbers of 9NI steel inner tanks, it is a common practice in similar projects both domestically and internationally to use automatic welding for circumferential seams and manual welding for vertical seams. However, manual welding has the disadvantages of a poor working environment, low work efficiency, and unstable welding quality. To effectively address this issue, China Global has made the automatic welding of the vertical seams in the storage tanks at the Tangshan LNG receiving station’s emergency peak-shaving support project team a key focus for research and development. The project department is responsible for the organization and practical implementation of the project, and promptly established a project team composed of relevant personnel from CNPC Jingtang LNG Co., Ltd., Beijing Huanyu Company, Beijing Xingyou Project Management Company, and Huanyu No. 6 Construction Company. 　　The relevant person in charge of the project team stated that, based on tasks such as current situation analysis and research, feasibility analysis and decision-making, selection of welding equipment and materials, process testing and evaluation, as well as project implementation and assessment, the team conducted a thorough evaluation of welding technologies and equipment. They also organized well-known domestic and international welder manufacturers to compare automatic butt welders, and through on-site operations, they assessed these machines in terms of welding quality, welding efficiency, and operability. Ultimately, the appropriate welders and welding materials for the site’s needs were selected, five welding process evaluations were carried out, and welding procedure manuals that met the requirements of on-site construction were prepared.