JPS5846991B2 - Welding assembly method for bottom plate in low temperature tank construction - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a method of assembling the bottom plate of a large storage tank by welding it from both sides in tank construction using the jack-up method, and particularly when the bottom plate of the inner shell of a double-shell low-temperature tank is targeted. suitable for

The conventional method is to first perform various operations such as arranging, welding, and inspecting the bottom plate on a stand or support, and after completing the bottom plate assembly, a sealing material is attached to the outer periphery of the bottom plate and the bottom plate is lifted by near raising. The second method is to dig a groove in the foundation in advance and install a supporting support or pedestal in this groove. The bottom plate is placed on top of the base plate, and the bottom plate is assembled by welding, inspection, etc., and after the bottom plate is assembled, the supporting support or pedestal in the groove is removed and the groove is filled. Thirdly, the bottom plate is assembled on the pedestal or support. After completion, the bottom plate is supported with something that melts (for example, ice) after a certain period of time, and the pedestal or support is removed.

In these conventional cases, the first method has the disadvantage that it is dangerous because the worker removes the pedestal or support while operating the air pressure, and the second method is difficult to backfill the trench and is time-consuming. It has the disadvantage of being expensive and uneconomical.
Further, the third method has the disadvantage that it is difficult to secure the melted material, and furthermore, when ice is used, for example, there is a problem of disposing of the water generated by the melting, making it impractical.

In addition, as a fourth method, after assembling the bottom plate using the first method, the bottom plate is lifted from the roof frame or side plate using a number of wires, the pedestal or support is removed, and the bottom plate is gradually moved by manipulating the wires. There are devices that lower the bottom plate, but with this method, it is very difficult to evenly lift or lower the bottom plate, which has a large surface area and is a heavy object, while adjusting the tension of many wires. Another drawback is that it requires a dog-related device.

The present invention completely eliminates the drawbacks of the conventional case. After completing the annular pearlite concrete on the outer tank bottom plate, an annular plate is placed on the pearlite concrete, and an annular plate is placed on the annular plate. Side plate feeding roller blocks are arranged at predetermined intervals, and then a part of the inner tank side plate is assembled in an annular shape on the roller blocks, and connected to the upper end of the side plate to assemble the inner tank roof, and inside the tank. Arrange the supports for the inner tank bottom plate arrangement,
After arranging the base plate base material on the support and performing welding and various inspections on the bottom plate, a hydraulic jack was installed directly below the inner tank side plate and between each of the roller blocks, and the entire inner tank was climbed onto the hydraulic jack. Later, the bottom plate was jacked up at least to a height commensurate with the jacking down on the cold insulation layer, the entire inner tank was supported by a frame, the roof and bottom were connected with wire, the support was removed, and the annular The bottom plate in low temperature tank construction is characterized by fixing a ring-shaped partition plate around the entire upper surface of the plate, then constructing the bottom cold insulation layer, jacking down the entire inner tank, and lowering the bottom plate onto the cold insulation layer. This is a core liquid assembly method.

The configuration of the present invention will be explained using examples and drawings.
In Figure 1, an outer tank bottom plate 3 is assembled on the tank foundation 2, and an annular pearlite concrete 4 is placed on the outer tank bottom plate 3.
After completing the above, a roller block 1 for feeding the side plate 6 is placed on the annular plate 5 on the pearlite concrete 4.
6 are arranged at predetermined intervals in accordance with the circumferential position of the side plate 6.

In FIG. 7, the roller block 16 consists of a roller support portion 16a and a roller 16b pivotally supported by the roller support portion 16a.
A channel 16c is placed on the roller 16b and receives the weight of the side plate 6 at the bottom of the channel.

The side plate 6 is placed on the channel 16c and can smoothly move on the roller 16b.

A part of the inner tank side plate 6 is assembled in an annular shape on this roller block 16, and connected to the upper end of this side plate 6 to form an inner tank roof part 9.
, and in parallel with this assembly work, as shown in Fig. 2, supports 17 for arranging the inner tank bottom plate are arrayed and erected on the outer tank bottom plate 3 inside the tank, and channels 18 are arranged as appropriate on these supports. The bottom plate base material is placed on top of this channel 18, and welding and assembly from both sides and various inspections are performed to complete the assembly of the entire inner tank bottom plate 8.

Next, a hydraulic jack 24 is installed directly below the inner tank side plate 6 and between each of the roller blocks 16, and the hydraulic jack is used to at least jack down the entire inner tank and later the bottom plate 8 onto the cold insulation layer 7. The entire inner tank is supported by the frame 19 after being jacked up to the appropriate height. To explain this embodiment with reference to FIGS. A hydraulic jack 24 is installed directly below the side plate 6 via a hydraulic jack jig 25 to which a pipe 27 is fixed.

In this case, since the tip of the hydraulic jack 24 is inserted into the halved short pipe 27, installation is easy and a stable state can be obtained after installation.

In this state, perform the jack-up operation to raise the channel 16 by one stroke, and then use the stacking type mount 19 to
While supporting C, perform the jack-down operation, then raise the hydraulic jack 24 by one stroke using another stand, and perform the jack-up operation again.After that, repeat the above operation until the jack is lowered to the specified height. The entire tank is raised and supported by a pedestal 19.

Next, as shown in FIG. 3, the roof part 9 and the bottom plate 8 are connected with a wire 20, and if necessary, the bottom plate 8 is slightly lifted by a turnbuckle 10 interposed in the wire 20, and then supported as shown in FIG. 17 and channel 18
At the same time, as shown in FIG. 9, the partition plate 23 is fixed in a ring shape to the bottom plate stiffener 22 which is fixed and protruded in a ring shape around the entire upper surface of the annular plate 5, and if necessary, the lower outer periphery of the side plate 6 is fixed. After suspending the rainwater infiltration prevention cover 21, construction of the bottom cold insulation layer 7 is carried out, and as shown in FIG. 5, the entire inner tank is jacked down, the bottom plate 8 is lowered onto the cold insulation layer I, and the wire 20 is removed.

Thereafter, the inner tank is jacked up using a special composite jack 1 shown in FIG. 6 via a receiving platform 11 and a receiving rod 12, and the entire inner tank is completed by a known jacking method.

In addition, a drainage ditch 15 with a buried channel facing down is provided as appropriate to drain rainwater to the outside until measures are taken to prevent rainwater from entering the inner tank.

According to the present invention, firstly, the assembly work of the side panels and the roof part and the bottom plate assembly work are performed in parallel, so the construction period can be significantly shortened, and secondly, the bottom part is kept cool by the partition plate on the annular plate. Rainwater will not infiltrate during layer construction.
Thirdly, welding and various inspections of the bottom plate can be carried out completely and safely from both sides on the support.Fourthly, the inner tank can be supported on a frame and the construction of the cold insulation layer can be carried out while it is suspended from the roof with wires. Therefore, there is no danger at all.Fifth, raise the entire side plate and roof group using a hydraulic jack, adjust the amount of rise to match the amount required to lower the bottom plate later, and then connect the roof and bottom plate with wire. Moreover, since the entire inner tank is supported by a frame, it is safe to work inside the tank, and the bottom plate can be lowered onto the cold insulation layer very smoothly after the support is removed, which is extremely effective in terms of safety, shortening construction time, and reducing costs. Effects are observed.

[Brief explanation of the drawing]

All of them are for detailed explanation of the present invention, and FIGS.
The figure is a vertically cut end view showing the order of the assembly method, Figure 7 is a vertically cut end view of the roller block part, Figure 8 is a vertically cut end view of the part showing the installation of the hydraulic jack, and Figure 9 is the figure 4 FIG. 3 is a longitudinally cut end view of the peripheral part of the annular pearlite concrete in FIG. 1... Special composite jack, 2... Tank foundation, 3... Outer tank bottom plate, 4... Annular pearlite concrete, 5... Annular plate, 6...Inner tank side plate, 7...Bottom plate cold insulation layer, 8...Inner tank bottom plate, 9...Roof part, 10... ...Turnbuckle, 11...
- Receiving platform, 12... Receiving frame, 13...
Frame, 14...Outer tank side plate, 15...Drain groove, 16...Roller block, 16a...
...Roller support part, 16b...Roller, 16c...Channel, 17...Support, 18...Channel, 19...
・The receiver is a stand, 20... wire, 21...
... Rainwater intrusion prevention cover, 22 ... Bottom plate stiffener 123 ... Partition plate, 24 ... Hydraulic jack, 25 ... Hydraulic jack jig, 2
6...channel, 27...halved short tube.

Claims (1)

[Claims] 1. After completing the annular pearlite concrete on the outer tank bottom plate, place an annular plate on the pearlite concrete, place side plate feeding roller blocks on the annular plate at predetermined intervals, and then remove the roller blocks. Assemble a part of the inner tank side plate in a ring shape on top, connect it to the upper end of the side plate to assemble the inner tank roof part, arrange supports for arranging the inner tank bottom plate inside the tank, and place the bottom plate base material on the support. After welding and various inspections of the bottom plates are performed, a hydraulic jack is installed directly below the inner tank side plate and between each of the roller blocks, and the hydraulic jack is used to insulate the inner tank side plate and the roof, and at least later the bottom plate. The inner tank is jacked up to a height commensurate with the jacking down on the layer, the entire inner tank is supported by a pedestal, the roof and bottom plate are connected with wire, and the supports are removed.
In the construction of a low-temperature tank, which is characterized by fixing a ring-shaped partition plate around the entire upper surface of the annular plate, then constructing the bottom cold insulation layer, and then jacking down the entire inner tank and lowering the bottom plate onto the cold insulation layer. How to weld and assemble the bottom plate.