Diaphragm power jack

Abstract: Method for increasing the distance between two faces, inserting into a space between the two faces a diaphragm power jack, the shape of which being adapted to the shape of the space, the diaphragm power jack comprising two abutting sheets (15,16) being sealingly bonded along the entire circumference, a pipe penetrating the bond, injecting a pressurized fluid through the pipe to the interface between the two sheets (15,16) thereby forcing the sheets apart whereby substantially all the energy from the pressurized fluid being converted to forces perpendicularly to the sheets.

Description: The Present invention is related to a diaphragm power jack and a method of utilizing same. In numerous situations within many fields efforts have been made to increase a distance between two parts in a quick and efficient way. Such a situation occurs when two flanges which have been clamped together, are to be loosened. In such case one of the flanges should be moved away from the other or even both flanges should be axially displaced. In many other cases the aim is to remove or displace only one of the parts between which a gap exists. This is the case by partitioning a subject into smaller parts which is the case in stone quarries, when removing a concrete outer layer from a pipe, etc. The need for a small and effective tool to provide a very strong\force in a selected direction, substantially without loss of energy in other directions will increase productivity and the accuracy of the performance substantially. In connection with repairs of pipelines of the above mentioned type a considerable amount of time is used for removing the outer concrete layer to give accessibility to the pipe itself for repairs maintenance or modifications. It is in fact known to cut tracks in the concrete around the exterior circumference and likewise longitudinal cuts whereby hydraulic tools are used to press the sections apart in a tangential direction, resulting in braking the concrete out in small pieces. The forces from the tool may be released between parallel flat or cylindric sheets. The forces will be directed perpendicularly to the plane of the flat sheets or perpendicularly or radially to the cylindric plane of cylindric sheets. In the latter case the direction is radially inwardly from a stronger outer cylinder or radially outwardly from a stronger inner cylinder, of which the first case will be a clamping operation. Repair of pipelines on difficult accessible places, such as at the sea bed, is time consuming and in many ways very difficult if repair work is to be made by welding. A ruptured pipeline usually is cut and a new portion inserted which portion thereafter has to be welded to the pipeline at both ends. The method and tool according to the present invention very efficiently solve the above mentioned problem operations in the above mentioned application fields as well as others by concentrating the force input almost completely to the desired force direction, perpendicularly to the sheets, if plane or cylindric, the direction being linear or radial. The above mentioned objectives are achieved with the method and tool according to the present invention as defined with the features stated in the patent claims. US,A,4,026,584 discloses a coupling for locking together two conduits. Pressurized fluid is iserted between an outer metal sleeve and an inner elastomeric tubular member, which is thereby pressed against said two conduits. The conduits can be held together temporarily or permanently as desired depending on the nature of the pressurizing material used. The inner tubular member includes a ridge being placed between the adjacent ends of the two conduits, thereby centering the coupling in relation to said two conduits. Figures 1-3 disclose the diaphragm power jack according to the present invention as used to sealingly connect two substantially abutting pipes 13 and 14. The diaphragm power jack according to the present invention for this purpose comprises an inner cylinder 16 and an outer cylinder 15 being sealingly connected at both ends such as by welding and being provided with at least one pipe 3 (not shown in Figs. 1-3 for the purpose of pressurizing the power jack. The outer cylinder 15 is suitably provided with outer strengthening flanges 17 and the inner cylinder 16 is suitably provided with inwardly protruding acute shaped cams 18 at least along selected portion thereof. The inner cylinder 16 furthermore comprises outer grooves 4 along selected portions in the axial direction, thereby partly weakening the material of the inner cylinder 16, partly creating a space for receipt of redundant material from the inner cylinder 16 during the shrinkage operation. The fluid used may be water or oil and preferably a plastic material in a liquid form when being injected through the pipe 3 under high pressure, thereafter curing and hardening to maintain or even increase a permanent high pressure from the outer cylinder 15 to the inner cylinder 16 and further to the pipes 13 and 14. In a further embodiment the diaphragm power jack according to the present invention also may be used to sealingly connect two pipes having different outer diameters, the outer and inner cylinders 15 and 16 thereby being manufactured correspondingly and preferably comprising two separated interface, each having slots 4.

Claims: A device for interconnecting in a sealing manner the end portions of two substantially aligned pipes (13, 14), comprising an outer (15) and an inner (16) sleeve which are sealingly joined at their ends for the forming of an intermediate, closed annular space to which a pressure medium may be supplied, so that the inner sleeve (16), by hydraulic pressure influence, is pressed to sealing contact with the abutting end portions of the pipes (13, 14), CHARACTERIZED IN that the outer as well as the inner sleeve (15 resp. 16) are formed from metal, the inner sleeve (16) forming a clamping sleeve which is subjected to shrinking under the hydraulic pressure influence, that the inner sleeve (16) is provided with a plurality of longitudinally extending grooves (4) which are uniformly distributed over the outer surface of the sleeve for receiving sleeve material which is brought to flow during the shrinking, thereby causing the sleeve (16) to maintain its circular cross-section during the shrinking, and that the inner sleeve (16) further is provided on its inner surface with a plurality of inwardly projecting, peripherally extending ribs (18) penetrating in the shrinking process into the outer surface of the pipes (13, 14) and forming leakage barriers. A device according to claim 1, wherein both sleeves (15, 16) are made from steel. A device according to claim 1 or 2, wherein said pressure medium is a curable medium which, after curing, maintains the pressure after installation of the device.

Inventors: KNUTSEN HANS, KNUTSEN, HANS
Applicants: POWER DIAPHRAGM TECHNOLOGY A S, POWER DIAPHRAGM TECHNOLOGY A.S.
Application year: 1993
Main classification: F16L17
IPC codes: F16L17