JPS6018766B2 - How to launch a marine structure from a quay - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a rig, SEP (Self E16vatin
The present invention relates to a method for launching a marine structure having legs such as gFlat (rm) from a quay.

S used for oil drilling rigs or bridge construction
When constructing offshore structures such as EPs that have a platform and legs, they generally have a tilting slipway, or are constructed in a dry dock and then launched into the water. Ship docks and dry docks are originally ship construction facilities, and may overlap with the above-mentioned marine structure construction and ship construction.

For this reason, the marine structures are constructed on the horizontal land surface near the quay. Pier-built rigs are generally launched in the following manner.

In other words, first, a submersible purge is docked at the berth of the ship, the rig is pulled out and placed on top of the purge, then the purge is sunk until the rig can float due to the buoyancy from the eyes, and then the rig is towed from the quay. It's a process. However, this method has the following drawbacks.

■ The purpose of such a wet purge is to transport the main cargo, and the ship is normally chartered for a period of about one month or more.

Therefore, chartering a ship for a period of about one week for the purpose of launching a ship is of little benefit to the purge company, and it is therefore difficult to charter a suitable purge ship to coincide with the timing of the ship's launch. ■ Purge equipment is not always equipped with a highly accurate ballast adjustment device, and therefore requires a long time to adjust the ballast in accordance with load fluctuations due to tides and rig transfers.

■ It is necessary to select an appropriate purge for each rig depending on its shape, weight, size, etc., but it is not always possible to charter a purge with optimal conditions.

■ It is necessary to install a skid rail extending from the ship's platform to the chartered purge, and to remove it after the work is completed.

All of these drawbacks increased the cost of launching operations, and there was much room for improvement.

In order to eliminate the above-mentioned drawbacks, for example, as shown in Fig. 1 A, B, C, and D, the launching pad 2 is extended from the pier 1, the rig 3 is pulled out (or pushed out), and when the rig 3 reaches a predetermined position, the leg is removed from the rig. 4 can be hung down to stand on its own, and then the overhanging launch platform can be removed, but in this case as well, it is necessary to install and remove the launch platform at the back every time a launch is made.

This invention was made after consideration to further improve the above-mentioned drawbacks, and will be explained below with reference to the drawings.
2 to 7 sequentially illustrate the steps of the launching method according to the present invention.

The rig 3 built on the platform quay 1 is moved to the launching point by a known method, and when a part of it starts to overhang the platform quay 1, the legs 4a of the overhanging part are suspended into the water. Figure 3).

A skid 5 is provided on the seabed in the launching area of the quay and has a gentle downward slope toward the shore. Launching carts 6a, 6b, and 6c are set in predetermined positions on the skid 5 of the bracket. There is. Now, when the leg 4a at the end protruding from the quay 1 hangs down and comes into contact with the trolley 6a (
(Fig. 3), the movement of the rig is resumed (Fig. 4), but at this time, the leg 4a at the tip is gradually extended as the rig 3 moves, and the rig 3 is moved while always keeping it horizontal. .
When the rear end of rig 3 is still on the quay 1 side, the rear leg 4
b, 4c and then twill them onto the remaining launching carts 6a, 6c (Fig. 5). After re-moving the rig 3 and completely leaving the quay 1 (Fig. 6), the legs 4a, 4b,
Gradually shorten 4c. By going through these steps, the rig 3 will finally float on the water with its buoyancy (Fig. 7), and thereafter be towed to another quay or site using a known method. The launching carts 6a, 6b, and 6c can then be returned to their original positions so as to be ready for the next launching.

It goes without saying that the number of launching carts 6 can be increased and the positional intervals can be set arbitrarily. This invention has the above-mentioned configuration, and since the rig is launched while sliding on the sloping skid, it requires less power and can be launched easily from the quay, so the work can be completed in a short time.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing a model of a conventional launching method, and FIGS. 2 to 7 are explanatory diagrams sequentially illustrating the launching method of the present invention. 1... quay, 3... rig, 4a, 4b, 4
c...leg, 5...skid, 6a, 6b, 6c...
...Launching truck. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] 1 Launching area A skid that slopes gently downward as it goes offshore is installed on the bottom of the water, and a trolley that moves on the skid, so that the legs hanging from the tip of the marine structure protruding from the quay reach the trolley. After that, the truck is moved at the same time as the structure is moved, and the rear leg of the structure is moved to the other truck, and then the structure is moved to a predetermined position, and then the platform is lowered and raised above the water surface. A method for launching a marine structure from a quay, which is characterized by being able to float.