Views: 0 Author: Site Editor Publish Time: 2024-07-17 Origin: Site
With the continuous development of the petrochemical industry, the demand for storage tanks is increasing. For many years, the manufacturing of storage tanks mainly adopts the central column method, air blowing method and water floating method for storage tank construction. Due to the gradual development of large storage tanks, some construction technologies can not meet the construction requirements, and the use of hydraulic lifting inversion method in the construction of large storage tanks has become a trend. The technical requirements of hydraulic lifting inversion method are not difficult, safe and reliable, the construction method uses less materials, the installation speed is fast, and the various construction parameters of the storage tank are easy to adjust and control, which can avoid the risk of roof falling and blowing accident caused by the use of air blowing method. It is currently a relatively ideal new method for the construction of storage tanks. This paper introduces the construction method and construction principle.
The upper and lower unidirectional clamping head is installed on the hydraulic jacking frame distributed on the inside of the storage tank. The upper clamping head is equipped with a hydraulic cylinder, and the power comes from the central console. The high-pressure oil is sent to the bidirectional cylinder (upper clamping head) through the hose, and the reciprocating action of the cylinder is realized through the reversing valve.
The piston rod is hollow, and there is a steel jacking rod in the middle, which can complete the stepping work of the jacking rod when the cylinder is reciprocating. The jacking rod drives the bracket on the jacking frame, and the bracket moves along the track of the bracket, and stops when the expansion ring temporarily fixed with the lower part of the tank wall is lifted to the lower part of the second circle of wall panel. After the installation of the second circle of wall panel and the first circle of wall panel are welded, the bracket is lowered, the first circle of wall panel is supported by the second circle of wall panel, and then the second circle of wall panel is expanded. The second circle of wall panel expansion ring is supported by the pallet plate, and then uprated and fixed, so reciprocating, so that the tank body is lifted, and the construction process requirements of the flip mounting method are realized.
Tank prefabrication and foundation acceptance → welding of tank bottom plate → welding of 1st round wall panel and wrapping Angle steel → Installation of hydraulic jacking device and expansion ring → Welding of 2nd round wall panel coaming and outer longitudinal seam → Lifting of 1st round tank wall → Welding of 1st and 2nd round wall panel welding → Falling of expansion ring and re-installing expansion ring → Welding of tank top and labor protection facilities → Repeat step 3 Ring wall panel → Repeat the above steps until the last ring wall panel is welded → removal of the jacking device → welding of the large corner seam and shrink joint at the bottom of the tank → overall test of the tank → anti-corrosion and heat preservation → completion.
Hydraulic jacking inversion method is used to construct large storage tanks, which has the following characteristics:
(1) Less high-altitude work and good safety. Basically ground operation;
(2) Occupy less space. Can be constructed in a narrow area;
(3) Construction machinery can be reused in storage tanks of different specifications except expansion rings;
(4) Hydraulic mechanism, small size, uniform lifting;
(5) Change a single control to a central control;
(6) Continuous jacking is changed to step jacking, and the jacking height is controllable to prevent uneven jacking;
(7) The construction quality is easy to guarantee. It is mainly reflected in: the roundness of the tank wall is good, and because of the expansion ring, it is very easy to find the alignment of the ring seam welding of the wall panel. The girth welding deformation is small and the flatness is good. Under the action of expansion ring, the girth welding stiffness is greatly increased, which effectively inhibits the shrinkage deformation. Tank verticality is easy to ensure, because each jacking frame can be individually adjusted;
(8) Strong adaptability. This method is suitable for the construction of fixed roof and floating roof tank with more than 1000m3, and the roof of the tank should be reinforced to prevent construction deformation when it is used for the construction of floating roof tank without roof.
(9) Low construction cost and good economic benefits.
Hydraulic jacking upside-down method is an ideal new method for storage tank manufacturing and installation. It is suitable for the manufacturing, installation and construction of more than 1000m3 arch tank, inner floating roof tank and no roof tank, especially for the manufacturing and installation of more than 20000 m3 arch tank, inner floating roof tank and no roof tank, and has the advantages that can not be replaced by other construction methods. It has broad development prospects and is worth popularizing and applying.
