JPS62397B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for laying pipes made of concrete-coated steel pipes by welding and joining them with high efficiency on the bottom of an ocean floor or the like on a pipe lay barge on a laying ship.

Traditionally, when laying pipelines underwater,
As shown in FIGS. 1 and 2, a group of pipe transfer rollers 4 fixedly arranged on the deck of the laying ship 1
On top of the water, there is a connected pipe 2' that continues to the bottom of the water.
and put the pipe 2' on the tensioner 5.
maintains a constant tension on the hull, and connects the new joint pipe 3'
is transferred from the stockyard S on the deck to the bow side by a longitudinal feed roller 6, then transferred horizontally on a transfer 7 and transferred to a centering machine 8, and at a work stage 9A, a new joint pipe is formed by a centering machine 8. 3' is centered, and one to two layers of welding are applied so that it can move in the launching direction. During this time, other work stages 9B to 9E and 10 to 13
In each case, perform the following tasks.

9B: 2nd to 3rd layer welding, 9C: 3rd to 4th layer welding, 9D: 4th to 5th layer welding, 9E: 5th layer to finishing layer welding, 10: Inspection of welded part (X-ray photography judgment), 1
1: Welding rework if necessary, 12: Anti-corrosion coating, 13: Concrete coating.

In addition, when the assigned work for all stages is completed, the work for each work stage is interrupted, the hull is moved forward by one new joint pipe (usually 12 m long), and the pipe is directed from the bottom to the bottom by the above length. It will be launched.

The above work is repeated to proceed with the pipe laying work, but since the launching time takes 1 to 2 minutes, in the case of 5 stages, the loss time will be 5 times the total welding work time by 1 to 2 minutes. become. Furthermore, when welding is performed using an automatic welding machine, the loss time is five times the time taken to attach and detach the machine. Furthermore, newly joined pipes are usually of irregular length, and the length is not constant between 10 to 13 meters, so the position of the joint often deviates from the 8th to 9th stage, causing the joint to move out of the stage position, or when being transferred. It may overlap with rollers, tensioners, etc., making it impossible to perform the bonding work, and also disrupting the time cycle, resulting in a great deal of time loss.

In addition, conventionally, when joining pipes on a laying ship, (a) alignment of the welded ends of the steel pipes, (b) welding of the steel pipes, (c) welding quality inspection of the joints (using X-rays, etc.), ( d) Corrosion-proof painting work on the joints, and (e) concrete coating work on the joints (for weight adjustment) are being carried out in sequence.

Furthermore, in order to process each of the above-mentioned operations in an assembly line, stages for each operation are arranged in series to perform so-called series joining operations. Furthermore, among the above-mentioned operations, welding and welding operations require significantly longer work time than other tasks, so welding and welding stages are set up at 4 to 5 or more than 6 locations to perform welding and welding operations. It is being divided into parts.

In addition, in actual laying work, the work assigned to each stage is processed within an approximately equal cycle time, and after all stages have finished their assigned work, the work is temporarily suspended and the laying vessel is moved forward to complete one section of pipe. The pipes are lowered from the stern toward the bottom of the water, and by repeating the above operations, the joined pipes are successively launched from the stern and laid on the bottom of the water.

In order to speed up the installation process as described above, (A) automate welding to shorten the welding time, (B) subdivide the welding work stage into multiple stages, and (C)
It is possible to eliminate loss time from the installation cycle time. However, in the case of (A) above,
Since time is required for attaching and detaching the automatic welding machine and initial adjustment for each stage, overall welding time cannot be shortened. In the case of (B), the hull length increases due to the increase in the number of stages, the number of welding workers increases, and equipment costs and labor costs increase.
In the case of (C) above, the conventional method involves assembly line work with almost no loss time.
The problem is that there is a 1-2 minute pipe launch time during the 5-10 minute cycle time during which all stages of the welding operation must be interrupted.

On the other hand, it is also conceivable to connect a large number of pipes on land to form long pipes, transport the long pipes onto the laying ship, and join the long pipes together. An extremely large crane ship is required to transport the long pipe, and the transport work is difficult, and equipment such as a crane on the laying ship becomes large.Furthermore, if the pipe is long, it may damage the surrounding surface. This makes it difficult to perform the work of spraying concrete for weight adjustment, and there is a risk that the long pipe may be bent during transportation work.

In view of the above-mentioned points (A) and (C), this invention provides a movable work stage on board the ship so that the welding work on the ship can be continued after centering the joint of the steel pipes. It enables continuous welding work even during launch work, and when using an automatic welding machine, eliminates the loss of installation and removal time, resulting in lower equipment costs and
It is possible to significantly improve welding efficiency with low labor costs, expand the adaptability to irregular lengths of pipes to be joined, and eliminate the disadvantages of transporting and joining long pipes. The purpose of the present invention is to provide a method of joining pipes for laying under water that is possible.

3 to 9 show an embodiment of the present invention, in which a pair of left and right launching rails 14 extending along the pipe laying line are installed at the centering welding work position on the bow side of the laying ship 1. The launch trajectory and
A return track consisting of a pair of left and right return rails 15 extending parallel to the launch rail 14 and the return rail 15 is arranged on the side thereof.
have the same rail spacing and are fixed to the deck of the laying ship 1 or to a support beam 17' attached thereto.

A vertical axis 16 is disposed in the center between the ends of the launch trajectory and the return trajectory, and the vertical axis 16
The lower part of the is fixed to the deck or support 17, and a bow rotary disk 18 is arranged between the bow side ends of the launch track and the return track, and a bow side rotary disk 18 is arranged between the stern ends of the launch track and the return track. A rotary disk 19 on the stern side is disposed, and a bearing 20 attached to the center of each rotary disk 18, 19 is fitted to the vertical shaft 16. Two sets of relay rails 21 having the same rail spacing as the spacing between the launching rails 14 and the spacing between the return rails 15 are fixed on both the left and right sides, and the rotating disks 18,
By rotating the relay rail 19 by 180 degrees, the relay rail 21 can be selectively connected to the launch rail 14 or the return rail 15.

A support roller 23 that rolls on an annular rail 22 fixed to the deck or support stand 17 is attached to the lower part around each turntable 18, 19, and the deck or support stand 17 is equipped with a rotation reducer. A motor 24 is fixed, and a drive gear 25 fixed to the output shaft of the motor 24 with a reduction gear is connected to a rotary disk 18,
19 is meshed with a driven gear 26 concentrically fixed to the drive gear 19. The traveling frame 27, on which a worker can ride, is made of steel plates, shaped steel, etc.
Wheels 28 rolling on the launch rail 14 or the return rail 15 are attached, a motor 29 with a traveling reduction gear is fixed, and a drive gear 30 is fixed to the output shaft of the motor 29 with a reduction gear. A driven gear 31 fixed to the wheel 28
The intermediate gear 32 that meshes with the traveling frame 2
It is attached to 7.

A traverse guide frame 33 is fixed to the front and rear portions of the traveling frame 27, and the traverse guide frame 33 includes a traverse reducer-equipped motor 3.
A screw jack 35 for fine horizontal movement driven by a screwdriver 4 is attached, and a traversing support 36 that is moved in the left-right direction by this is slidably fitted. cylinder 3 in the screw jack 38 for vertical fine movement driven by the motor 37 with
9 is fixed, and a piston 40 in the screw jack 38 is guided by a cylinder 39 and can move up and down and also rotate (oscillate) within the cylinder 39.

A pipe support stand 42 is pivotally attached to the upper end of the piston 40 by a support shaft 41 extending in the left-right direction, and a metal fixed shoe 43 for supporting the pipe is attached to the pipe support stand 42 on the stern side. A metal freely rotating roller 44 for supporting a pipe is attached to the pipe support base 42, and the fixed shoe 43
The already joined pipe 2 is supported by the free rotating rollers 44, and the newly joined pipe 3 is supported by the freely rotating rollers 44, so that the pipe and the centering welding cart can be moved relative to each other.

On the traveling frame 27, a welding machine power source 4 is installed.
5. A control panel 46 and all other mechanical equipment necessary for welding work such as welding gas, manual welding machine, automatic welding machine, semi-automatic welding machine, centering sensor, etc. are installed. In addition, a power receiving device 47 is attached to the side of the running frame 27, and constantly receives power from a power feeding rail 49 installed continuously on the side of an awning device 48 covering each track via the power receiving device 47 for welding. power source for the centering sensor, power source for the centering control device, power source for the centering drive, and power source for driving.

Next, a case will be described in which the pipe joining apparatus configured as described above is used to join pipes for laying under water.

First, a new centering welding cart 50A to be reused is waiting on the rotary disk 18 on the bow side, and the already joined pipe 2 is supported by a number of transfer rollers 51 on the laying ship 1 and laid by the tensioner 5. It is moored to Ship 1 and continues to the bottom of the water. Furthermore, the centering welding cart 50F on the stern side has completed the entire work cycle and has finished moving in the launching direction together with the joined pipe 2.

In the process of movement in the launching direction, the wheels of the centering welding cart 50B pass the relay rail on the rotary disk 18 on the bow side, and then the rotary disk 18 is rotated 180 degrees.
The next new centering welding cart 50A is rotationally moved from the return rail 15 to the launch rail 14. This new centering welding cart 50A has moved on the launch rail 14 to a position where it can support the new joint pipe 3. In addition, the newly joined pipe 3, which has been suspended and waiting by the upper crane device 51, is lowered onto the freely rotating roller 44 of the centering welding cart 50C and the fixed shoe 43 of the centering welding cart 50B (see FIGS. 3 and 4).
(see figure).

Next, after connecting or replacing the power cable hose for the inner clamp attached to the inner surface of the pipe welding part, the centering welding cart 50B is driven toward the stern side, and the pipe end of the newly joined pipe 3 is connected to the already joined pipe. 2 and the pipe ends facing each other on the centering welding cart 50C, and joining by appropriately driving the centering devices (screw jacks for left and right fine movement and screw jacks for vertical fine movement) on both sides of the centering welding cart 50C. Center the parts.

In the case of welding using a manual welding machine, the welding work is started immediately, and the welding work is continued without loss time until all welding of the same joint is completed. In addition, in the case of welding with an automatic welding machine, the automatic welding machine is attached to the pipe end side of the joined pipe 2 during the entire work cycle time, and the welding pipe is set and adjusted to the joint pipe end line, so centering is completed in this case as well. The arc can then be started immediately.

Joint work other than welding is completed in other stages, and when the state is reached where there is no problem in launching and moving the pipe after centering and first layer welding on the centering welding cart, immediately move only one pipe. launch it.

On the centering welding cart, it moves with the pipe as this cycle time repeats, continuing the joining operation until all welding operations are completed.

Welding of the joints on the centering welding cart 50F has been completed, and the free-rotating rollers and fixed shoe are lowered to wait in preparation for the next launch.

After the start of the next launch, before the centering welding cart 50E gets on the relay rail of the turntable 19, the turntable 19 is
Rotate 180 degrees and move the centering welding cart 50F onto the line of the return rail 15. Also, centering welding cart 5
0E rides on another relay rail on the newly set turntable 19 and launches.

On the other hand, the centering welding cart 50F is connected to the return rail 1.
5, and rides on the relay rail of the turntable 18 on the bow side, waiting for the next cycle.
A centering and welding worker rides on each centering and welding cart and performs the work while moving with the cart.

As in the above embodiment, if a type of centering welding cart with wheels that rolls on a launching rail is used, it is possible to support a large load, reduce movement friction, and reduce the pipe tensioner. The frictional resistance exerted on the wire is also reduced, making tension management easier, and furthermore, the cost of transport equipment for the laying line is reduced.

In the above embodiment, a type of centering welding cart that runs on rails is used.
Alternatively, a tracked vehicle or other vehicle may be used. Alternatively, a power generation facility may be mounted on the centering welding cart to obtain the necessary power.

As a means for transferring the centering welding cart to the launch rail or the return rail, as shown in FIG. A means for transferring via a relay rail 52 may be adopted, and as shown in FIG.
A means for moving the traverser with a relay rail in the left-right direction using a hydraulic jack 55 may be adopted, or a means for installing a return rail below the launch rail and moving the traverser with a relay rail in the vertical direction using a hydraulic jack may be adopted. Good too. Furthermore, the centering welding cart may be one that does not have a self-propelled drive device.

According to this invention, while moving a large number of centering welding carts from the bow side to the stern side, centering and welding and other joining of the already joined pipe 2 and the newly joined pipe 3 are performed on the centering welding carts. Since welding is carried out during the launch time, the time required from the start of welding to the completion of welding can be significantly shortened, and there is no need to attach or detach the welding machine at each stage, making the operation easy. In addition, there is no need for initial adjustment time for attachment/detachment, which reduces work time, and also reduces the number of times of attachment/detachment.
The rate of damage to the welding machine is reduced, and since all welding can be done by the same worker, quality control can be clarified and the pass rate of welds can be improved. Even if there is a length, there is no need for welders or workers to move for each joint. In addition, since the welding machine only needs to be attached and detached once for each joint, there is no need to reduce the time taken to attach and detach the welding machine. Therefore, when using an automatic welding machine, use an expensive one that can be attached and detached quickly. This eliminates the need for equipment costs, and since each centering welding cart can be moved independently, it can be easily adapted to handle irregular length pipes. Since installation and positioning can be carried out before starting centering welding, cycle time can be shortened, and the machinery and equipment on the centering welding cart can be maintained, repaired, and repaired during the return process of the centering welding cart. Management is easy because consumables can be replenished. Furthermore, since the centering welding trolley and the pipe do not move relative to each other, centering welding work can be performed without any problem even if the pipe moves back and forth with respect to the ship due to ship shaking, which eliminates loss time and improves operating efficiency. Furthermore, all work from centering to welding completion can be performed by the same team of workers.
Effects such as being able to reduce the number of personnel can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a side view for explaining a conventional method of joining pipes for laying on the bottom of the water, and FIG. 2 is a plan view thereof. 3 to 9 show one embodiment of the present invention, in which FIG. 3 is a schematic side view showing a state in which pipe joining work is being performed, FIG. 4 is a schematic plan view thereof, and FIG. Fig. 5 is a partially vertical front view showing a rotary disk on which the centering welding cart is placed, Fig. 6 is a schematic plan view of the centering welding cart, Fig. 7 is a schematic side view thereof, and Fig. 8 is a schematic plan view of the centering welding cart.
The figure is a cutaway side view showing the centering device in the centering welding cart, and FIG. 9 is a partially longitudinal sectional front view thereof.
FIGS. 10 and 11 are plan views showing other examples of a moving device for a centering welding cart between a launch rail and a return rail. In the figure, 1 is the laying ship, 2 is the joined pipe,
3 is a new joint pipe, 14 is a launching rail, 15 is a return rail, 18 is a bow side rotating disk, 19 is a stern side rotating disk, 21 is a relay rail, 22 is an annular rail,
24 is a motor with a speed reducer, 27 is a traveling frame, 29 is a motor with a speed reducer for traveling, 34 is a motor with a traverse speed reducer, 35 is a screw jack for left and right fine movement, 36 is a traverse support base, 37 is a speed reducer for lifting 38 is a screw jack for vertical fine movement, 40 is a piston, 42 is a pipe support stand, 43 is a metal fixed shoe for pipe support, 44
is a freely rotating roller.

Claims (1)

[Claims] 1 In the launching line on the laying ship 1, a large number of centering welding carts equipped with centering devices and welding machines and other joining machines are independently moved from the bow side to the stern side, and during the transfer The already joined pipe 2 and the newly joined pipe 3 are supported and centered by the centering device on the centering welding cart and welded by the welding machine. A method for joining pipes for laying on the underwater bottom, characterized in that the welding cart is returned to the bow side end of the launching line through a return line on the side or below the launching line.