Electric Chain Hoist Used in Vertical Storage Tank Installation

With the rapid development of China's economy and the improvement of people's living standards, the domestic demand and consumption of oil and refined oil and other resources are growing. In petroleum, pesticide, chemical engineering and other construction projects, large vertical cylinder vault storage tank is widely used because of its advantages of small area and low cost. According to the actual project of the oil depot renovation and expansion, the production and installation of three 8000m3 large vertical cylinder vault oil storage tanks are analyzed from four aspects: the installation method, the lifting device, the overall force analysis and the installation process, and the experience is summarized.

1. Project overview

This project has three 8000m3 oil storage tanks made and installed. The diameter of the oil tank is 26.5m, the height is 20m, and the weight of a single tank is about 180t. The main components are composed of the bottom plate, the cylinder body, the top cover, the winding ladder railing and the manholes of each nozzle.

The difficulty of the project is that the production and construction should be carried out at the same time, and the inflammable and explosive high risk areas of the oil depot should be comprehensively considered. There are ring fire passages around the oil tanks, which should not be occupied during the construction process and should be kept unimpeded. The new closed oil trap, sewage shed and accident pool are in the north, the oil tanks in operation are in the south, the reserved tank area is in the east, and the new oil platform and the operating oil platform are in the west. 

2. Selected method for installation of large oil tanks

Mechanical lifting (electric hoist) flip method first use jacks and other auxiliary tools to make the expansion ring, and fixed on the wall wall of the wall, so that the expansion ring and the tank become one, through the electric hoist device to lift the expansion ring to the predetermined position, the group of the upper and lower ring wall panels, through the expansion ring for layer by layer transport to complete the assembly and welding. The advantages are simple construction technology, easy to operate, good control of project quality and construction schedule, low cost, high construction efficiency and good control. The disadvantage is that it needs to be controlled manually, which is time-consuming and laborious. And now the labor costs are more expensive, increase a lot of cost input, and the construction hidden dangers are larger.

3. The construction device of electric hoist lifting inversion method

The construction device of electric hoist lifting inversion method is mainly composed of electric hoist, column, expansion ring, diagonal brace and adjustment device, etc. The lifting device is shown in Figure 4. 20 10t inverted chains are distributed on the concentric circles about 500mm from the tank wall inside the storage tank, and the lifting electric hoist is fixed on the flip column. The flip column is made of 159×8 steel pipe with a height of 3.2m. The upper lifting lug, base and reinforcement plate of the column are made of δ=16mm steel plate. Install 3 diagonal braces in 3 directions at 3/4 height of the column. The diagonal braces are made of ∠75×7. The Angle between the brace and the Angle between the brace and the bottom of the tank is 450, and the tank is installed with 1 column, which is used to connect each lifting column together to form a whole. The expansion ring is made of [16 rolling arc, which is divided into several sections according to the circumference of the tank, and the project is divided into four equal sections. During the installation of the expansion ring, four 16t jacks are used to tighten the expansion ring at the position of the fourth equal section of the expansion ring to make it close to the tank wall, and the expansion ring and the tank wall are fixed into one body through the gantry clamp, and the gantry clamp is set along the expansion ring every 1m. The four positions of the expansion ring with the jack top tight should avoid the flip column.

Based on the practical engineering, the manufacturing, installation and welding technology of 3 8000m3 large oil tanks are analyzed, and the application of electric hoist hoist inversion method in large storage tanks is summarized. It solves the installation problems such as difficult to control welding quality, insufficient precision of tank wall and tank top ring joint, and difficult to guarantee the overall lifting coefficient in the lifting installation of large storage tanks, ensuring that the project can be completed on time and with quality.