SE415586B - DEVICE FOR RECOVERY OF A PIPELINE PUBLISHED PIPE - Google Patents

Description

, §O 55 40 * drive belts to drive the machine forward. _ 7601333-3 Ä,. reliability m.m.

Known machines for digging ditches under a pipeline laid on the seabed, however, have a number of inconveniences in terms of both the practical design and working method as well as manufacturing and operating costs. * In practice, many varieties of conventional trenching machines are provided with tools, consisting of a plurality of blades which are attached in a bucket-like manner to the end of a motor shaft, which in turn is supported in a support frame and which can be rotated and tilted in some angles, to dig a ditch around a laid pipeline ..

Such digging blades are not suitable for carrying out excavation work in the solid seabed and, furthermore, the axles, due to their large weight, cause difficult problems in the design of guide means, by means of which different maneuvers are to be performed for digging in the seabed of different nature. 'Furthermore, conventional machines with roughly conically shaped' tools and with blades or tips at the ends of movable shafts are mounted in different kinds of frames, which are sometimes equipped with trawl tracks, the latter being driven by clumsy and unwieldy machines under different work stages, so that the excavation becomes very time consuming.

In addition, the devices for controlling the excavator, in cases where they are of the electronic type, are supported by an arm forming a unit with the frame or the vehicle carrying the excavating equipment, or, if they are of a mechanical type, arranged between the frame or the carrier. the body and the pipeline. In both cases, they are unreliable in terms of ability to move along the longitudinal axis of the laid pipeline.

Other known excavators are exposed to various imbalances, mainly in their transverse trimming due to occurring underwater currents, which are not sufficiently counteracted by applying forces to the frames. With regard to the varying shape of the bottom, where i.a. protruding rock or rock tips may occur, existing protruding arms can also be an obstacle to the excavator's progress. If the drive device, as is usually the case with known excavators of this type, is of the belt type. If the machine is towed along the bottom via a cable pulled by a vessel on the water surface, 50 55 40 7601333-3 assert many uncertainties. which is related to signaling systems, voltage variations in the towing wire, the towing vessel's rolling due to sea level rise and the machine's digging work on the seabed. The object of the invention is to eliminate these inconveniences and to provide a machine for digging a ditch under a pipeline laid on the seabed. The excavator according to the invention can be driven either by its own drive source or receive power via a cable from a ship which follows the movement of the excavator during the excavation along the pipeline. The disc-like support means of the machine for the excavation walls are arranged to completely surround the pipeline in order to crush and remove the bottom material. In this way, any deflection from the intended direction of movement is avoided, and the machine is further completely stabilized so that a transverse trimming is easily achieved, which may otherwise vary during the movement of the machine along the pipeline. The excavator according to the invention is further provided with two excavating devices, which are located at the ends of two support shafts and each comprises a cover and a jacket supporting a tool disc, which can be rotated, either centrally or eccentrically around a pipeline. The tool disc is equipped with serrated inserts that can process all kinds of minerals, including waste rock, and which dig up the bottom as the machine moves forward. The tool inserts are shaped so that they can machine the bottom regardless of the direction in which the two tool disc machines are advanced along the pipeline. They are operated in such a way that during the excavation work they rotate in opposite directions around the pipeline, whereby both an efficient excavation is obtained and a secure stabilization of the machine.

The excavator according to the invention is driven forward in either direction at the same time as stabilizing the machine. The propulsion takes place under the influence of two first, hydraulic jacks which on one side are attached to the side of the machine's support shafts and on the other hand to a sliding bridge, which is arranged on the support shafts via two scenery.

The sliding bridge supports via guides a first group of jaws, arranged above and on both sides of the pipeline, which jaws can be pressed against the pipeline under the influence of two hydraulic jacks and a rotary shaft, after a second group of jaws has been released from the pipeline. When the first two jacks, after being moved outwards, have ceased to actuate the support shafts, and consequently also the tool discs, in the digging direction by pressing on the first group against the pipe soldering pressed jaws, the second il, 76o1333-3 50 55 4 group jaws towards the pipeline while the first group of slopes is released therefrom, so that the first jacks can be returned to their initial positions. The second group of jaws, which are now pressed against the pipeline under the action of a hydraulic jack placed in a plane perpendicular to the longitudinal axis of the pipeline and which are driven by a control mechanism which detects any deviations in the excavator's normal vertical position, can exert a torque around the longitudinal axis of the pipeline, so that the machine is returned to its normal position. In this way, the position of the excavator is constantly trimmed during its movement along the pipeline in connection with the excavation.

When the machine is to be moved in the opposite direction, this takes place under the influence of two other, hydraulic jacks which act on the second group of jaws on the corresponding sweet, as described above. In this opposite direction of movement, the first group of jaws serve as trimming means after a completed movement and working step.

In summary, the excavator according to the invention thus comprises two support shafts, which at the ends support rotatable digging devices around the pipeline. The shafts are interconnected by means of two bridges, each fastened to both shafts via shaft journals, pins or the like, which can be rotated in seats in along sliding slides along the respective support shafts. that, while moving the machine along a pipeline, eliminating undesirable impact on the jaws when the pipeline bends, which would otherwise result in a skew of the machine in relation to the longitudinal direction of the pipeline.

At both ends of the above-mentioned support shafts are arranged metal covers, each mainly in the form of an upside-down U, which partly surround the pipeline when the machine is moved a short distance over and along it. The covers are partially closed by means of screens, which prevent excavated masses from penetrating between a cover and the pipeline, and in order to further reinforce this preventing effect, ejectors are arranged in connection with the screens, which ejectors run on wheels and follow the movement of the machine. with the pipeline. On the two covers are jackets, also in the form of an upside-down U, mounted which, when the machine is in operation, are rotated half a turn under the action of a hydraulic device, after which another jacket is moved in the axial direction. in between the legs of the first jacket, so that a jacket extending completely around the pipeline is formed. This casing carries a rotary shaft. The shaft journals on the bridges have a functional tool disc which, during the movement of the machine, rotates on the casing under the influence of the hydraulic motor arranged on the casing.

Excavation with the machine can be carried out in steps, so that at each step a digging depth is achieved, which corresponds to the radial extent of the digging inserts.

The jaws which are clamped to the pipeline suitably have relatively large abutment surfaces, so that the outer surface of the pipe, or any casing laid thereon, is not damaged. that the tool discs at the outer circumference have holes, channels or the like to allow the flow of excavated masses, which are brought in the direction of the suction pipe, where they are sucked away.under the ejector- Furthermore, it is suitable action, for example as shown in Italian patent specification 946,582.

The screens which are arranged in the covers, and which prevent the penetration of excavated masses into the covers, can also be provided with one or more wreaths with suitably designed groove curves, whereby this wreath or these wreaths with extra digging inserts can be located on the same or different radial distances such as the main digging inserts arranged on the tool disc. Furthermore, it is suitable that this screen, like the tool disc, has holes or channels for the flow of excavated masses.

Application of the excavator according to the invention to a pipeline can be carried out so that the machine is first lowered directly onto the M pipeline and trimmed by means of an air-filled trimming tank, so that the machine is in the intended vertical position, after which bottoms around the pipeline are sucked away with suction pipes. sufficient extent for the jacket parts to be able to be joined to a single jacket extending around the pipeline. Alternatively, the pipeline can be lifted from the bottom, for example by means of a device described in Italian patent specification 985. 196 after which the excavator is mounted on the pipeline in the manner indicated above.

.- The invention will now be described in more detail in connection with the accompanying drawings. Fig. 1a - Bb schematically shows how a machine according to the invention is applied to a pipeline lying on the seabed, Fig. 4 the machine shown in Figs. 1a - šb, seen from above, Fig. 5 a side view of one half of the machine according to the invention Fig. 6 shows a section through a part of the machine at one end thereof, Fig. 7 a view seen from above over a part of one end of the machine is sucked away after the machine has been placed over the pipeline 49. Fig. 8 is a side view showing a cover at one end of the machine, Fig. 9 is a cross section along the line A - A in Fig. 6, Fig. 10 is a cross section along the line B - B in Fig. 6. , Fig. 11 schematically shows a tool disc eccentrically located in relation to the pipeline and a screen with ejectors and guide wheels for the machine, Fig. 12 a larger and a smaller sector of a tool disc, Fig. 15 an equivalent to Fig. 12 with the two the parts assembled, Figs. 14 and 15 sections illustrating how two different digging inserts Fig. 17 is another side view of an excavator, Fig. 17 is a side view of an upper jaw, on which a guide is welded, Fig. 18 is a front view of the same parts as shown in Fig. 1; Fig. 19 shows a part of an upper jaw with the guide, Fig. 20 a longitudinal section through an upper jaw and with associated guide, Fig. 21 a side view of one of two bridges, which are hingedly connected to the support shafts of the machine, Fig. 22 is a cross-section through the bridge shown in Fig. 21, Fig. 25 is a side view of a part of an upper hill and a side-hill, Fig. 24 is a cross-section along the line C-C in Fig. 25. "an upper jaw and side jaws clamped to a pipeline, íig. Fig. 26 is a top view of an upper hill and two side slopes, and Fig. 26 is a rotary axis for lifting the upper hill.

Figs. 1a - šb show a machine 1 which can be trimmed by means of a floating reservoir 56, intended to place a branch over a control of two at a certain distance from each other at a certain distance from a stirring device 61, 62. pipe 49. fabric board 12 is located as an upside-down U. suction pipes 52 are provided, through which bottoms, sand or sludge. The purpose of this suction of bottoms is to enable the preparation of the machine for an excavation operation. The machine is driven by motors placed in a container 54, which can obtain their power via a narrow cable 60, which can, for example, lead to a fabric above the existing fabric. The reservoir Sá serves for trimming the machine both when immersing and applying it to the pipeline, as well as during ongoing excavation work.

As can be seen from Fig. 5, the excavator comprises two longitudinal support shafts 31 (only one of which can be seen in this figure) placed on each side of the pipeline H9 and supporting at both ends excavating devices and at the central parts devices for moving and stabilizing the machine 1. One of these two digging devices is shown in Fig. 5 and comprises a fixed cover 5, which is welded at one end of the shafts 31 and which has a cross section in the shape of one of the axial direction, the end of the screen 17 carries a number of wheels 19 intended to guide the machine 1 along the pipe joint of an inverted U. the covers a screen 17 is attached, as shown in Fig. 6. ning # 9.

As can be seen from Fig. 7, two male guides 16 with a salmon-tail cross-section for a larger jacket sector 2 are arranged on the fixed housing 5, which via rotary female guides 15 with the same cross-section are rotatable under the action of a hydraulic motor 29 (Figs. 5). via the gear rotatable from a position with the open part of the jacket directed downwards, in which position the jacket can be passed over the pipeline 49, to a position with this open part directed upwards, in which position the jacket part is fixed by means of a pin 25 at the fixed cover 5f The mantle sector 2 is then under the influence of hyd- This larger mantle sector 2 in turn carries via a pin and a groove 22 (fig. 6) with salmon tail-shaped cross-section a larger sector 7 of the tool disc 12. This later disc l2 is thus rotated ou 1800 together with the larger oral sector 2. In this position, when both the larger oral sector 2 and the larger disc sector 12 have been rotated so that their open parts are directed upwards, one steps on it fixed cover 8 arranged in operation, and displaces from left to right in Fig. 5 a smaller jacket sector along salmon tail-shaped grooves 9. This smaller jacket sector 5 carries via a stop pin 26 a smaller disc sector 4 of the tool disc 12. When the jack 8 hascompleted its work stroke, the smaller jacket sector 5 and the smaller disc sector @ are inserted, as shown in Fig. 10, with the salmon tail-shaped trades 15 in corresponding female guides until they are completely pushed to the bottom (Fig ._7), at the same time the stop pin 24 locks the smaller jacket sector 5 at the jacket 5. Under the influence of a jacket sector 2 and 5 formed in the drawing, not shown in the drawing. 7601333 -43 In the mathematical device, the pins 25 and 26 are then released, whereby the tool disc 1 supporting the digging insert; disengaged from the one by the tool disc 12 can now, under the action of a hydraulic motor 50 and a gear 64, be set in rotation.

Fig. 5 further shows in broken lines one of the wheels 19 which guide the machine 1 along the pipeline 49 and further channels 59 on the disc 12 for masses excavated from the bottom.

In addition, a screen 65 is shown on the disc 12, which protects the pipeline 49 from excavated masses and two of the digging inserts mounted on the tool disc 12, of which the insert 27 is part of an outer and the insert 28 an inner ring, which defines the cross section of an excavated channel. 1 moves to the right, as seen 1 rig. Fig. 5 also shows the extraction pipes 52, which are plated in pairs on each side of the pipeline 49 and arranged to suck under the action of an ejector 55 excavated masses which pass through the channels 59 from the tool disc 12 and remove them. through a mouth 55. In addition, dashed lines 52 are shown which are arranged in each of the support shafts 51 and which support a rotatable bridge 54. The latter assists in trimming the machine under the influence of movable arms 42 and the wheel 45, which is actuated by a pivot shaft 46. The bridge 54 is thus forced together with the other parts of the machine to assume the intended trimming position under the influence of a transverse jack 40 which is attached to a guide 55 (Fig. 17) on the bridge and arranged to be actuated by a body not shown in the drawings which senses the deviations of the machine from the intended vertical position.

Fig. 5 shows another of two jacks 48 for longitudinal displacement of the machine 1, which with one end is attached to the support shaft 51 and with its other end to the bridge 54. The upper jaw 59 is provided with a reinforcing list 58.

Fig. 6 shows, in addition to what has already been described, one of several ejectors 18, placed adjacent to the screen 17 and arranged to prevent excavated masses from penetrating into the interior of the fixed housing 5. Fig. 7 shows the smaller shell sector 5 in position to be displaced together with the smaller disk sector 4 along the guides 9 in order to form an entire shell 11 on which the completed tool disk 12 can rotate.

Fig. 8 shows the larger jacket sector 2 in cross section before it has begun to rotate along the nllings 16 in the fixed housing 5.

Figs. 9-26 illustrate in more detail the various parts described in connection with Figs. 1 ~ 8, 51 marking the center of the tool disc 12, 55 the pins on the bridge E4, 55 the guide on the bridge 54 and 56, 57 the groove in the bridge 54, into which the trade of the guide 55 of the bridge 54 is introduced. Furthermore, 43 mark shaft journals around which the jaws 41 are rotatable in the direction of and from the pipeline 49 under the influence of hydraulic jacks 44.

Claims (5)

7601333-3 10 EAIE-'JYIELRAY Method for digging a ditch (58) under a pipeline (49) laid on a seabed by means of a machine (1), characterized in that a pair of stationary covers (5) projecting below the machine (1) ) with an open, circular section is placed around the pipeline (49), that a jacket (II) with two sectors (2, 3) is connected to the respective cover, which jacket has a tool disc (12) divided into two sectors (4, 7), on which digging inserts (27, 28) are mounted, that one sector (2) of the jacket (11) together with one of the discs (12) of the disc (12) is rotated 1800 from an upper position to a lower position with respect to the pipeline (49), that the narrower sectors (3) and the disc (12) of the jacket (12) are moved forward to complete the larger sectors (2, 7) around the pipeline (49), that the complementary board (12) is rotated around the pipeline (49) for digging by means of the digging inserts, that a pair of bracket devices (61, 62) be placed at the rear of the machine with respect to the digging direction and clamped against the pipeline (49), that the machine is moved along the pipeline (49) with the stirrups initially clamped against the pipeline, after which the stirrups are moved to a forward position, that the vertical position of the machine is sensed for stabilization purposes and that the machine is moved relative to the pipeline (49) depending on the sensed position. ' Method according to claim 1, characterized in that the direction of movement of the machine (1) is reversed for digging in the opposite direction, u Machine for digging a trench (58) under a pipeline (49) laid on a lake bottom, characterized in that it comprises two support shafts (31), which at their ends support two stationary covers (5) in pairs. ) with an open circular section, on each of which, via circumferential guides (16), are, under the action of a hydraulic motor (29), rotatably arranged a first sector (2) of a jacket (11), with a second sector (3) of said jacket (11) is axially displaceable along guides (9) on the upper side of the fixed housing (5) under the action of a jack (8) arranged thereon to form together with the first jacket sector (2) of a closed jacket (II), which concentrically or eccentrically surrounds the pipeline (49), the jacket sectors (2, 3) being filled with circularly tapered front guides (22) for moving towards them. sectors (2, 3) corresponding sectors (4, 7) of a digging insert (27, 28) supporting tool disc (12), rotatably arranged below in actuation of a gear (64) and a hydraulic motor (30), and partly at its central portions support two hydraulically actuable bracket groups (61, 62) arranged for attaching the machine (1) to the pipeline (49) and for movement during stabilization of the machine (1) along the pipeline (49) while the machine is kept at the intended level by a reservoir (56) containing compressed air. Machine according to claim 3, characterized in that each of the stirrup groups (61, 62) comprises a semicircular bridge (34), which at their ends are mounted in guides (32) displaceable along guides arranged on the support shafts, the bridge (34) is rotatable along a likewise semicircular guide (35) via a groove (36) under the influence of a jack (40) oriented longitudinally transversely to the support shafts (31) and is actuated by a sensor for vertical trimming, which guide (35) ) carries both an upper fixed jaw (39) and storage pins (43) for four side jaws (41) which can be actuated in pairs by two double-acting piston rods, one end of two pivot rods (46) being mechanically connected to the upper, fixed jaw (39). ) ends, while the other ends of the pivot rods (46) are arranged to abut against the pipeline (49) via rotatable wheels (45) while two jaws (48) are connected to their ends for moving the machine (1) on the one hand with the semicircular bridge (34) and on the other hand with the support shafts (31). , Machine according to claim 3 or 4, characterized in that the digging inserts (27, 28) are mounted freely rotatable along two concentric circles on the tool discs (12), the digging inserts in the outermost circle being arranged to provide a digging surface front which inclined towards the axis of the tool disc (12), while the other digging inserts are arranged vertically in relation to said axis. MENTIONED PUBLICATIONS: