Abstract: A submarine plough is disclosed comprising a plough share 216 having a cutting edge 207. A heel 220 is arranged rearwardly of the cutting edge 207, and a plough beam 205 has an attachment portion for enabling a towing means 209 to tow the plough to cut a trench in the sea floor. The plough share 216 is pivotable relative to the plough beam 205 to adjust the vertical separation between the cutting edge 207 and the attachment portion. Front skids 204 are arranged adjacent a forward end of the plough beam 205 and hydraulic rams 219 pivot the plough share 216 relative to the plough beam 205. A cable is passed in an arcuate path into the trench rearwardly of the cutting edge 207 and heel 220.

Abstract: A liner bag for a manhole can have an improved durability after hardening with a fluid pressure barrier film left on the inner wall of a lined manhole, and a method of lining a manhole using the liner bag is capable of realizing a reduction in the number of steps involved in a manhole lining process to reduce a working time and a working cost.

Abstract: The invention relates to a process for introducing an optical cable, in the form of a microcable or minicable (1), in solid ground (17) with the aid of a laying unit (23). The microcable or minicable (1) used for this purpose comprises a homogeneous and pressurized-water-tight tube (8) which has an external diameter of from 2.0 to 10 mm and into which optical waveguides (3) are introduced.

Abstract: A method of repairing or reinforcing worn-out underground buried drainpipes by a resin transfer molding process using both flexible tubes and bagging films is disclosed. In the method of this invention, a reinforcement is primarily inserted into a desired position within a target worn-out drainpipe buried underground. The reinforcement consists of a fiber preform internally having a flexible tube, such as a silicon tube, axially extending along the central axis of the preform and wrapped with an adhesive-coated flexible film as a bagging film to provide protection from sewage or underground water. The flexible tube is, thereafter, expanded to bring the fiber preform into close contact with the interior surface of the target drainpipe. The opposite ends of the reinforcement are sealed with two lids. Thereafter, thermosetting resin is transferred into the fiber preform, thus allowing the fiber preform to be impregnated with the thermosetting resin.

Abstract: A device for digging and backfilling of ditches, in particular for laying pipes, comprising an automotive travelling mechanism (2) carrying a machine frame (4) with an upper structure, a boom (6) pivoted on the machine frame (4) and having a plurality of boom arms (8, 10, 12) connected with each other with hinges and an excavator bucket (16) pivoted on the free end of the boom (6) is provided with a milling/mixing rotor (22) mounted to the excavator bucket (16).

Abstract: A cable deployment system and method for laying a cable on the sea floor. The cable deployment system includes a cable having a first cable section connected to a riser cable section. The riser cable section includes an armor that is connected to a drum capable of containing a required length of the first cable section. A stinger is attached to the drum and shaped to allow the first cable section to exit the drum. The cable deployment system also includes a tensioning device attached to the drum. The tensioning device is capable of maintaining a tension in the first cable section during deployment of the first cable section from the drum. The method of deploying the cable in deep water from a surface vessel includes the steps of containing the first cable section within the drum and lowering the drum from the surface vessel. An end of the first cable section is secured to the sea floor and the first cable section is deployed from the drum onto the sea floor.

Abstract: A fiber optic cable (10) is buried below ground, either by direct burial, or by being pulled through a previously buried duct. During cable burial, the instantaneous resistance between the sheath and ground (the sheath-to-ground resistance) is continuously monitored. If the instantaneous sheath-to-ground resistance drops below a prescribed value, an alarm is generated, signaling a sheath fault. During burial, the length of cable paid out and placed underground is monitored, thus providing an indication of the relative location of the sheath fault.

Abstract: A method and apparatus have been developed which inserts and withdraws tubing from pipes without bending or kinking the tubing. Beneficially, the method and apparatus may be employed to insert and withdraw tubing to depths greater than ever possible before. The method involves using a thruster pig to provide force to inject the tubing. The thruster pig uses a pressure differential to urge the tubing into and out of the pipe. Advantageously, check valves or relief valves allow fluid to be pumped down the tubing and out the front of the thruster pig, and then to flow back through the valves and up the annulus between the pipe and the tubing.

Abstract: A continuous ditch excavator including a chassis having a forward portion and a rear portion, first and second motive devices carried by the chassis in laterally spaced-apart relation to each other for cooperatively driving the chassis along a ground surface, the first and second motive devices defining a centrally-disposed excavation work area therebetween, and an excavating auger mounted on the chassis in the excavation work area forwardly of the rear portion of the chassis and rearwardly of the forward portion of the chassis for penetrating and excavating a ditch in the ground as the chassis is driven along the ground, said auger defining a pivot point about which the first and second motive devices are adapted to rotate the chassis to control the direction of ditch excavation.

Abstract: A device (6) for attachment to a pipe (7 to be installed in the ground has load cells (17) for detecting a pulling force applied to the pipe (7), as the latter is pulled through the ground, an inclinometer (18), for detecting the inclination of the device (6), and a pressure transducer (20) for detecting the pressure surrounding the device. Data representative of the pulling force, inclination and pressure is stored in the device (6) and protected against unauthorised access by a security code or procedure, so that a verifiable record of the pipe installation process is available.

Abstract: A method of replacing damaged parts of wastewater channels with inserted parts, e.g. optical cables, includes removing a section of the channel, positioning a lower half-shell (1) below the inserted part (2) at the removed section of the channel, passing an attachment element (3) having two ends (3a, 3b) around the inserted part (2), feeding the attachment element (3) through at least one opening (4, 6) of an upper half shell (5), placing the upper half shell (5) on the lower half shell (1), attaching the upper half shell (5) to the lower half shell (1), attaching the upper and lower half shells (5, 1) to neighboring channel sections, pulling the ends of the attachment element (3) tight to press the inserted part (2) against the inner surface of the channel, and filling the opening (4, 6) with a sealing compound (7).