Domestically pioneered installation using the \"integral jacking and sliding method for spherical tanks\"
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This post was last edited by The wise are enlightened on 2024-2-8 at 14:59. Recently, CNPC Seventh Construction Company used the domestically innovative \"integral jacking and sliding method for spherical tanks\" to successfully position two 3,000-cubic-meter acrylonitrile spherical tanks at the Sinochem Quanzhou 260,000-ton/year acrylonitrile project, thus putting this sliding method into practical use. Due to the fact that the official foundation of the spherical tank is too close to the original tank area, this results in insufficient space for safe operations, a higher risk of damage to the tank, and difficulties in ensuring installation accuracy. These issues mean that the requirements specified in the \"Safety Regulations for Special Operations in Chemical Production Units\" cannot be met, and therefore on-site welding work cannot be carried out on the official foundation. Thus, CNPC 7th Construction Company carried out all the processes required for spherical tanks, such as assembly, welding, and heat treatment, at the off-site prefabrication site ； Lifting can cause irreparable cracks at the points where stress is applied to the tank; therefore, hydraulic jacking and pushing from the bottom of the pillars are used instead to avoid stress being applied to the tank ； Transporting using SPMT axis cars will block the fire access routes; therefore, concrete slides at the same level as the permanent foundation are laid, extending from the foundation of the prefabrication site to the permanent foundation, and slip carts are used to transport the spherical tanks into place……
This sliding process overcomes the challenges posed by the large size and weight of the spherical tank, its high center of gravity, and the long sliding distance. It also requires high standards regarding the bearing capacity of the foundation as well as the strength and stability of the sliding tracks. There is a risk that the tank could tip over or become unstable due to foundation settlement or deformation of the sliding tracks.
After it’s in place, weld inspection should still be carried out.
I’m not entirely sure about the specific installation procedures, but logically speaking, only airtightness and hydrostatic tests are required. Weld inspection has already been carried out at the prefabrication site; what if welding inspection is done again after installation and the results are unsatisfactory? Will welding be done again? This area does not meet the requirements of the \"Safety Regulations for Special Operations in Chemical Production Units,\" and therefore on-site welding work cannot be carried out here.
The overall push-sliding method provides a new solution for narrow areas and scenarios where welding is not possible in renovation projects.
Thank you for sharing; let’s not forget forum development in the new year.
Non-destructive testing, overall heat treatment, as well as airtightness and thermal insulation must all be completed. In 2007, our company successfully carried out the overall translation of a 400-cubic-meter spherical tank by 50 meters in Bangladesh
I wonder how the overall sliding method addresses the issues related to inconsistencies with the procedures specified in the GB50094 standard? Also, should a leak test be conducted after it is in place?
Thank you for sharing. A gas tightness test should be conducted again