[Haichuan Chemical Salary News] Dongguan Juzhengyuan propane cryogenic tank begins water filling tests
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On November 7th, with the order to start work, the Dongguan 120,000-cubic-meter propane cryogenic tank project reached another important milestone. Since the installation of the first bottom liner plate on April 12, it took a total of 211 days to complete the construction of the main interior tank; the first-pass welding success rate was 98.5%. This project involves filling 127,000 cubic meters of water, with 2 300KW submersible pumps being used simultaneously. The current water level is 1.8 meters, and the water filling rate is 60 mm per hour; it is expected that the filling work will be completed by the 26th of this month.
The Dongguan Juzhengyuan propane cryogenic tank project, constructed by Sinopec Fourth Construction Company, uses A537 CL2 cryogenic steel for its tank body. For the first time, this material is being used in inner tank bodies with automatic vertical seam welding technology; it is currently the largest cryogenic tank project in China that employs this technology. Compared to previous cryogenic tank welding projects, the Dongguan Juzhengyuan project presents challenges such as larger tank sizes, tighter deadlines, greater amounts of welding work, and thicker wall panels.
At present, for the LNG receiving station projects built by CNPC, Sinopec, CNOOC, and various local entities in China, since the application of the automatic welding process for the vertical seams of the outer tanks of bimetallic LNG cryogenic storage tanks in the Dongguan Jiu Feng LNG project, this technology has been successfully utilized in actual engineering projects. Referencing the technical requirements for vertical seam welding of 9%Ni steel and the criteria for weld procedure qualification from various projects undertaken by the company, such as the Jiu Feng LNG and Zhoushan LNG projects, as well as drawing on the welding experience gained from the construction of the 30,000-cubic-meter low-temperature tank in the Jiaxing Phase II project, a targeted weld procedure test plan for the automatic welding of A537 CL2 low-temperature steel was developed from the perspective of on-site construction. The weld procedure tests were carried out using domestically produced A537 CL2 low-temperature steel. In accordance with the welding process test plan, the project department assigned welders who have experience in welding A537 CL2 low-temperature steel to carry out the welding; the welding test plates were sent to a qualified third party for inspection and testing. Through this welding process test, the feasibility of the gas-shielded automatic welding process for longitudinal seams in LPG propane cryogenic tanks made of A537 CL2 low-temperature steel was demonstrated, and it was confirmed that all mechanical properties of the welded specimens meet the specified requirements.
The project leader attaches particular importance to the first use of automatic welding for this material. Before starting work, assign dedicated personnel to inspect all welds, wall panels, and bottom plates of the tank on a daily basis. At the same time, conduct regular random inspections of the radiographic test films in collaboration with the supervisor, the owner, and the Guangdong Provincial Quality Supervision Station, in order to ensure zero errors, zero accidents, zero risks, and no hidden dangers.
On April 9, the gas lifting of the low-temperature storage tank for the first phase of Shenzhen Juzhengyuan Co., Ltd., a subsidiary of Guangwu Holding Group,’s \"1.2 million tons per year propane dehydrogenation to produce high-performance polypropylene project\" was successfully completed. The low-temperature storage tank is an important facility in the first phase of the propane dehydrogenation project; the outer tank is constructed of prestressed concrete, while the inner tank is made of A537CL2 low-temperature steel structure. Pneumatic jacking work primarily involves the use of balance systems, sealing systems, blower systems, etc., and relies on buoyancy and lifting force to smoothly lift the tank’s roof and aluminum ceiling to the elevation at which the pressure ring is installed, as part of the construction process. After the vault has been lifted to its installation position, welding is carried out between the vault and the pressure-bearing ring while maintaining a certain pressure inside the tank; this welding process fixes the vault to the pressure-bearing ring, thereby completing the installation of the vault. The gas lift of the low-temperature storage tank is a key milestone in the construction of the first phase of the Juzhengyuan propane dehydrogenation project, marking that the construction of this phase is about to enter the full equipment installation stage. The 1.2 million tons per year propane dehydrogenation project for producing high-performance polypropylene is one of the key projects of Guangwu Holding Group’s effort to shift focus from speculative activities to tangible operations, to vigorously develop advanced petrochemical-related industries, and to achieve a transformation toward a more industrial-oriented business model. Upon completion, this project is expected to generate annual revenue of over 10 billion yuan and substantial profits for Guangwu Holding Group, thereby helping to preserve and increase the value of state-owned assets. It will also help to fill the demand gap in the polypropylene industry in South China, contributing effectively to the development of the Guangdong-Hong Kong-Macao Greater Bay Area.
May I ask what the wall thickness of this tank is?