Abstract: An apparatus has a base plate having a plurality of penetrating holes, a vertically movable plate slidably mounted on guide posts, and a stripper plate slidably mounted on the guide posts and hung from the movable plate. A plurality of stripper pins are vertically slidably mounted in the stripper plate. Each stripper pin is arranged to be inserted in corresponding one of the penetrating holes of the base plate. A sheet holding plate for mounting a product sheet is provided to be detachably mounted on the base plate. The stripper pins are arranged to push each molded rubber product on the product sheet in the corresponding penetrating hole so as to strip it from the product sheet.

Abstract: A method and apparatus for forming separated stacks of perforated, zigzag folded sheets from a main stack comprises a feed conveyor adapted to receive the folded sheets and to transmit such sheets on their folded ends to a sheet spreading and cutting station. Two adajcent sheets of the main stack are spread apart at the spreading and cutting station by a divider plate and a separator blade to provide sufficient clearance for a flexible cutter to extend into engagement with the perforation therebetween thus forming a relatively small, separated stack of folded sheets from the main stack. This separated stack is then transferred to a discharge conveyor for further handling.

Abstract: Apparatus for breaking an optical fiber comprises fiber gripping units (2 and 4) each comprising a rigid block (6 or 6') having adhered thereto a strip (8 or 8') of a resilient material, for example a synthetic felt, the blocks (6 and 6') being relatively movable between an open position to receive an optical fiber (OF) between the resilient strips (8 and 8') and a closed position to clamp the fiber (OF) between the strips (8 and 8'). A fiber holder (9) is provided for applying a pulling force (P1) to the fiber (OF) to cause it to slide between the resilient strips (8 and 8') in the closed position of the blocks (6 and 6') Before being inserted between the strips (8 and 8'), the fiber is formed with a V-shaped notch (N) at which the fiber is to be broken.

Abstract: A device for breaking open cylindrically packaged rolls of coins, has a base and an anvil centrally located on the upper surface of the base. The anvil includes a lower portion affixed to the base and an upper portion against which the roll of coins are struck to break open the same.

Abstract: An automatic ampoule cutter including a driving device, cutter mechanism having a cutting member, a fixing member and a clamping member, a slant board, a collector and a fan, whereby when an ampoule is placed into the cutter mechanism, a micro switch is touched and activated by the ampoule to make the driving device drive the cutter mechanism, urging the cutting member, fixing member and clamping member to tightly clamp the ampoule, permitting the cutting member to rotate for several turns and cut a groove on the neck of the ampoule so that a knocking member can knock off the conic head to roll down on the slant board into the collector, and the cutting chips is blown by the fan also into the collector, and when the left ampoule is taken out to leave the micro switch, the operation of the cutter then stops.

Abstract: An apparatus for the automatic separation along predetermined bending fracture lines in basic ceramic platelets of hybrid electronic circuits includes a support plate provided with grooves on its lower face defining bending lines juxtaposed with the fracture lines of the platelet urged against an upper face of plate by upper pressing members being in contact with each of single elements of the platelet defined by the fracture lines and lower retractable members controlled in a predetermined sequence for successive bending of the plate and the platelet subdivided in a plurality of single elements.

Abstract: First and second tube sections (12, 14) are dimensioned so as to enable telescoping receipt of an end portion of one within the other. A pair of parallel slots (36) in the end portion of the second tube section (14) is slidingly received onto a break pin (28) transversely secured within the first tube section (12). A further break pin (38) is transversely secured within the end portion of the second tube section (14). An optical fiber cable (17) passes through the tube sections and between the break pins (28,38) such that on the tube sections being axially separated, the fiber cable conforms about the break pins in relatively small radii severing the fiber cable.

Abstract: An attachment for a hydraulic excavator including a pair of jaws mounted on a frame and having offset points or projections on the jaws to apply localized pressure onto a rock or coral piece for breaking the workpiece. Both jaws are movable and operable by individual hydraulic cylinders. The direction of thrust against the jaws being tangential to the arc of movement of the pins for connecting the cylinders to the jaws at a location approximately midway of the operational arc of the jaws.

Abstract: A device for splitting tablets has a base and a cover. A tablet to be split is held in a recess in the base, and a knife edge is provided in a corresponding recess in the cover, the recesses being larger in one dimension than the largest dimension of the tablet. Closing the cover severs the tablet while eliminating or minimizing crumbling.

Abstract: A method for cutting workpiece made of such a glass or ceramic material having relatively large thickness. A workpiece having one surface on which an incision is previously formed is placed on a flat plate which has a Young's modulus smaller than that of the workpiece and which is placed on a surface plate, so that the surface having the incision of the workpiece faces the upper surface of the flat plate. A pressing load is then applied downwardly through a pressing member to the surface opposite to the surface having the incision of the workpiece locally along the incision. The workpiece is thus cut by the bending moment due to the difference of the Young's moduli of the workpiece and the flat plate without generating noises or forming chips.

Abstract: A dispenser for dispensing discrete lengths of longitudinally corrugated strips of wiping web material from a source of uncorrugated continuous length wiping material. In the device the web material is payed through and between converging longitudinally disposed projections whereby the corrugations are formed. The corrugated web is then fed between cogwheels, then to an egress part of the dispenser through which the web projects for a distance. The cogwheels may be provided with a servering means. To dispense the web projecting from the dispenser it is pulled outwardly resulting in obtaining a desired severed length of wiping material.

Abstract: A method and apparatus for breaking a scribed workpiece such as a semiconductor wafer is taught. Briefly stated, the semiconductor wafer is disposed between two elastomeric foils, one of which is adhesively attached to the side of the workpiece which is not scribed. The foils are stretched and a force is then applied to the sandwich so that the workpiece breaks along the scribed lines. Due to the elastomeric nature of the foils the broken pieces separate slightly and remain separated after breaking, thereby preventing damage to adjacent surfaces of the workpiece.

Abstract: A device for removing a ring closed and locked by a fastener containing a protruding fastener lock, the device includes a fastener engagement member having a wall and a floor which define a recess adapted to receive the fastener therein. Attached to an outer surface of the fastener engagement member is a lever member adapted to exert force on the fastener when the lever member is moved, thereby breaking the ring locked to the fastener.

Abstract: Apparatus is provided for making a cookie preform from a continuous cookie dough rope by inserting finger means into said rope in a direction generally transverse to a longitudinal axis of said rope and displacing at least selected ones of said finger means at a velocity relative to the velocity of said rope sufficient to stretch said rope to the breaking point to separate said portion from said rope, whereby said portion has at least one surface formed by said stretching action to have a coarse appearance.

Abstract: A conventional closure or cap for a tablet-container is formed to have a recess of predetermined depth and shape to loosely receive therein a tablet preferably provided on at least one side with a stress-raising notch or score mark, so that the application of a lateral force on an upper portion of the tablet by a finger or thumb of the user will cause the tablet to break approximately along a plane extending across the tablet from the bottom of the stress-raising notch. In another aspect of the invention, the tablet preferably provided on at least one side with a stress-raising notch or score mark is laid with the notch downward into a recess provided with a partial movable base so that the application of force on the exposed surface of the tablet by a finger or thumb of the user causes the tablet to be supported close to its ends to thereby experience a break at the notch.

Abstract: A method and apparatus for cutting polycrystalline silicon rods which comprise applying pressing forces at at least two positions on a plane perpendicular to the longitudinal axis of a polycrystalline silicon rod at a plurality of positions symmetrical to said axis.

Abstract: Apparatus for subdividing a stack into a number of piles of overlapping sheets has an elevator which can move a stack upwardly in stepwise fashion between a belt conveyor and a horizontally reciprocable carriage for a pusher and a blade-like horizontal separating element which extends beyond the pusher in a direction toward the conveyor. When a selected part of the stack extends above the level of the upper reach of the conveyor, the carriage is moved toward the conveyor so that the separating element penetrates between two sheets of the stack and the pusher thereupon transfers the pile above the separating element onto the conveyor. Two hold-down devices enter the gap which is formed in the stack as a result of penetration of the separating element to prevent the topmost sheet of the remaining portion of the stack from participating in the movement of the separating element toward the conveyor. The thickness of the rounded tip of the separating element is less than 0.9 millimeter.

Abstract: A concrete crusher of the type comprising a rotatably mounted frame carrying both the crusher forming members and the shearing members, and wherein said shearing members are formed by at least one fixed arm and one of the arms of the crusher, the latter arm being articulated to said frame and adapted so as to give to the shears the maximum opening when it is in a maximum closed position of the crusher.

Abstract: An apparatus for cutting a workpiece of glass, ceramic, or like material on a surface of which an incised cutting line has been formed beforehand has a backing roller made of an acrylic resin on which the workpiece is laid so that the incised line is in contact with the backing roller, a pressure applying roller with an annular pressure applying rim around its outer cylindrical surface for applying localized pressing force on the surface of the workpiece directly opposite the incised line, and a feeding mechanism for feeding the workpiece, thus pressed between the pressure applying rim and the backing roller, in the direction of the incised line, whereby the localized pressing force is applied over the entire length of the incised line. The localized pressing force creates a bending moment in the workpiece, producing a tension stress which becomes a maximum along the incised line, whereby the workpiece fractures and is thereby cut along the section in which incised line lies.

Abstract: A wafer supplying apparatus including a supply ring to which a wafer sheet having semiconductor pellets adhered thereto is attached, a ring holder provided on an X-Y table of a pellet pick-up device, the ring holder supporting and placing the wafer sheet onto the upper surface of a cylindrical portion of the ring holder having an external diameter smaller than the internal diameter of the supply ring, a pressing ring provided above the supply ring, a pusher which pushes down the supply ring around the cylindrical portion of the ring holder through the pressing ring, and a fastener which fastens the pressing ring to the ring holder after the supply ring has been pushed down by the pusher.

Abstract: A gate breaker, for the finishing of cast iron, consisting of a hydraulic cylinder which is operatively connected to a processing unit, preferably a wedge, at one end at least. The hydraulic cylinder is suspended from a circular clamp (29) with an internal semicircular track for two or more rollers (27) connected to the hydraulic cylinder. Between the hydraulic cylinder of the tool unit and the rollers (27) there is a pivot which permits pivotal movement of the gate breaker about a transverse axis of the unit.

Abstract: An apparatus for folding and cutting a continuous length of paper. The apparatus includes (1) a folding mechanism for folding the paper into a stack of sheets, (2) a vertically movable supporting table for supporting the sheets, and (3) a cutting mechanism for cutting the paper.

Abstract: A method and device are provided for separating trimming losses from a sheet having a plurality of products formed thereon with star-shaped scraps between the products. In one embodiment, the sheet is placed on a sheet supporting plate. The sheet is positioned between a blanking plate and a plurality of pushing rods fixed to a mounting plate. Each of the pushing rods has a piercing pin extending from the free end thereof for penetrating into a corresponding star-shaped scrap. The blanking plate has through holes formed therein which correspond to the pushing rods and star-shaped scraps such that the pushing rod passes through a corresponding through hole. The inner diameter of each through hole is smaller than the outer size or greatest dimension of the star-shaped scrap. When the star-shaped scrap is pushed through the through hole by the pushing rod, it deforms and passes through the through hole.

Abstract: An assembly for breaking tablets is disclosed where a tablet is secured on a surface through the action of a crank working on two flanges and subsequently broken with pressure applied to a hammer which is contacted with the tablet.

Abstract: An apparatus having improved safety and performance characteristics for the removal of a coating from a tubular member, and particularly adapted for the removal of a concrete weight coat from submerged oil pipelines, comprising a generally C-shaped rigid frame member which is maintained in proper alignment by contact with the upper coated surface, is provided with a plurality of opposed, inwardly directed driven crusher blades located proximate the ends of the frame member and controlled driving means which are adapted to move the crusher blades. The method comprises positioning the apparatus on the coated pipeline, crushing the coating, raising the entire apparatus to free the fractured coating from the pipeline, retracting the crusher blades, and moving the apparatus to a new position on the pipeline.

Abstract: The invention provides an automatic vertical glass cutting machine, including a cutting-wheel holder carriage which is movable vertically over a predetermined height of a vertical rap under the action of an actuator of the pneumatic kind, the cutting-wheel holder being fixed to the carriage by means of a rocker arm movable with respect to the body of the carriage which has a mechanism for locking said rocker against the carriage controlled by a fixed cam.

Abstract: A prehensile container is provided for demounting and storing used hypodermic needles and/or surgical blades pending their ultimate disposal. The same hand that holds the container can actuate the closure blade by finger force to clear an orifice for passage of a used hypodermic needle. When the end of the syringe to which the needle is affixed abuts the mouthpiece of the orifice, the finger force can be released to hold the needle between the edge of an aperture of the shutter blade and an edge of the orifice, so that the needle can be separated by withdrawal of the syringe with one hand while holding the container with the other. Another exertion of finger force will let the used needle drop into the container and a second release will restore the closed condition of the container. Internal baffles obstruct the exit of stored needles, to prevent an unauthorized person from extracting a needle from the container by opening the access orifice.

Abstract: A dispenser for the insertion of spacers between the strings of tennis, squash and badminton rackets includes a body having a delivery groove formed therein. The delivery groove is adapted to receive an interconnected strip of spacers and dispense the spacers individually between intersecting strings of a racket. The delivery groove may include a raised portion to allow the strip of spacers to be manually advanced within the device and a pair of prong-like projections for separating a pair of intersecting racket strings. The prong-like projections may have an abutment edge for positioning the interconnected strip of spacers.

Abstract: A roll splitter for splitting apart rolls of paper that have been rewound onto separate cores positioned adjacent to each other on a common shaft such that adjacent edges of the rolls overlap. The roll splitter includes a vertically-extending, fixed post, a fixed base, a frame pivotably attached to the base, a pair of contact plates pivotably attached to the frame and being spaced apart from the post a distance sufficient to allow a roll of paper to be inserted therebetween and positioned on either side of the post, and a double-acting cylinder motor pivotably attached to the post and frame for pivoting the frame toward and away from the post. Two rolls having adjacent, overlapping edges are positioned between the post and the plates such that the overlapping edges are in registry with the post and are split apart as the cylinder motor urges the contact plates against the rolls, thereby urging the rolls against the post at the overlapping edges.

Abstract: A system and method for use in quickly and easily removing bearings or collars from shafts, without damaging the shafts, is disclosed. The system comprises a frame to which are attached a slider and breaking point members, which slider and breaking point members can be adjusted to accept bearings or collars of varying sizes, and contain them in a stable manner so that a force can be imparted to the breaking point members, thereby causing the bearing or collar to break and be removed from the shaft to which it was mounted. The system is constructed to allow replacement of the slider, breaking point members and other elements, for instance when they become worn through use.

Abstract: An attachment for the boom structure and hydraulic system of a hydraulic excavator, including a pair of relatively swingable jaws for crushing concrete slabs and the like, each of the jaws having a grid like jaw structure with elongate rigid plates extending outwardly from the pivot structure, there being a multiplicity of tapered tooth like projections on the grid structure of the jaws, the tooth like projections being of various lengths, at least one of the jaws being connected to the hydraulic system to open and close the jaws to apply pressure and fracture concrete structures being gripped and crushed.

Abstract: A method and apparatus wherein individual plastic articles are sheared from a cartridge of such articles and conveyed pneumatically through a pneumatic conduit to a desired position.

Abstract: An apparatus for dividing a pill into two portions (i.e., halves, quarters, etc.), such that one portion is immediately accessible and the second portion is captured for later use. The apparatus includes an anvil-like platform adapted to support a pill in a generally horizontal mode. A centering means is sized and oriented for positioning the pill on top of the platform in such a way that the pill is bisected by a cleavage plane, regardless of the size of the pill. The centering means preferably includes a pair of converging walls, with each wall lying in a plane that is substantially perpendicular to the plane established by the platform. A gap between the convergent ends of the two walls lies in the cleavage plane, and the gap has a width which is just sufficient to receive a movable blade. The blade may be moved between two major positions, with one being a raised (or retracted) position and the other being a completely lowered position.

Abstract: An apparatus for breaking and stripping coins from a coin roll includes a pair of elements each having a channel adapted for receiving a portion of the coin roll and support members supporting the pair of elements in a first orientation adjoining one another with channels aligned for simultaneously receiving an elongated roll of wrapped coins. The support members further permit translational movement of the elements relative to one another to a second orientation with channels transversely displaced to break the coin roll simultaneously received in the pair of channels. Each of the elements is provided with a pair of reciprocable arms for gripping the portion of the roll in the channel. Stripper members are passed through the channel and arms of each of the elements and are tiered to first remove coins from the gripped wrappers and then remove the wrapper from the element.

Abstract: The present invention relates to a method and apparatus for segmenting groove molded building boards. In a preferred embodiment, a sheet of groove molded board is conveyed onto a first apparatus which separates the side edge trim scrap from the board. The board then passes onto a segmenting apparatus comprising a first horizontal conveyor, an inclined conveyor, a second generally horizontal conveyor, and adjustably mounted roller assemblies. The first apparatus removes the side-edge trim scrap from the board and the second segmenting apparatus breaks the groove molded board transversely along the groove molded lines. In addition, the second apparatus separates the leading and trailing edge scrap so as to provide individual board panels which require no additional trimming. As an alternative, two segmenting conveyors can be used in tandem so as to remove all of the scrap, thereby obviating the need for the first trim-scrap removing apparatus.

Abstract: An ampule opener is provided for automatically opening ampules. The ampule opener is especially suitable for use in a robotic sterility test system and is provided with a pneumatic actuator means releasably connected to an ampule opener arm. The head of an ampule is positioned with its neck on a knife edge so that when the ampule opener arm is rotated by the actuator means, the arm applies a pressure on the head of the ampule and the ampule head drops away.

Abstract: Cleaving of an optical fibre (2) is achieved by bringing a fibre cleaving blade (3) into lateral contact with such a fibre. Undue intrusion of the blade into the fibre during prior art cleaving processes can damage the fibre so as to detract from the quality of the resulting cleaved fibre end surfaces. Improvemets in the quality of the resulting end surfaces can be obtained in relation to prior art techniques by superimposing a relatively small amplitude vibratory component on a relatively steady movement of the blade towards the fibre. This can also enable the conventional use of a backing anvil at the cleaving location to be dispensed with, thereby removing danger of contamination from the anvil.

Abstract: A semi-full cut semiconductor wafer is put on an adhesive sheet attached to a ring frame. Then, the semiconductor wafer is pushed upward from the back surface of the adhesive sheet by a rotatable breaking member in the shape of a disk the edge portion of which is triangular in section. In this state, the ring frame is moved so that the breaking member may not deviate from dicing lines, whereby the semiconductor wafer is divided into a large number of chips.

Abstract: Apparatus for cutting substantially flat ceramics pieces, having a frame for supporting the piece to be cut, over which a head carrying a cutting line-scoring tool slides. A freely-oscillating fork is arranged rearward of the position of engagement of the scoring tool, with legs on the fork resting on the piece to be cut on both sides of the scoring or marking line. A cranked lever is articulated on the frame and has a forward end projecting through an opening in the frame and a forward arm actuated by the tool carrier head at the instant the piece is broken or severed, to cause the rearward end to protrude and support the piece for breaking or severing.

Abstract: A connecting rod fracture machine for fracture separating the caps and bodies of integrally formed connecting rod workpieces includes a cryogenic cooling station for embrittling the large ends, a fracture station for fracture separation of the embrittled cap and body portions, a warming station for returning fractured assemblies to ambient temperature and transfer mechanism for moving the workpieces between stations. The fracture station includes separable pilots for receiving the large end bores of the pieces to be fractured, an impact separation ram for rapidly separating the pilots to effect fracture separation and anti-rotation clamp means movable with the respective pilots and requiring linear separating motions of the caps from the connecting rod bodies.

Abstract: A two part tool fits into the crankshaft bore of a partially manufactured connecting rod for an internal combustion engine and expands the bore to break the bore housing into two pieces, one of which comprises a bearing cap to permit installation of the rod onto a crankshaft journal. The tool is retracted to fit within the bore for the bearing and a high pressure acts on a piston to provide a high enough force to move two parts of the tool away from each other in direction perpendicular to a bisecting plane that lies along the central axis of the bore and to split the one piece bearing housing into two parts along a place defined by notches which weaken the bearing housing in selected areas. The piston is centered on the bisecting plane of the connecting rod so that the forces are balanced to ensure uniform, repeatable operation.

Abstract: The apparatus for separating folded and perforated or creased endless or reel papers, which form an uninterrupted stack, comprises a conveyor belt 9 conveying the same to a separating station, in order to permit an automatic separation of the stack into individual stacks 7a with a predetermined number of paper sheets. For this purpose, a separating sword 2 is moved preferably from below between the sheets of the stack, so that a stack 7a is formed with the desired number of individual sheets. The small cavity 10 running in the longitudinal direction and formed by the separating sword 2 is used for receiving a knife 4, which is moved at right angles over the stack, in order to separate the same at a perforation or fold. Pivotable removal bolts 1 are used for conveying away the separated stack 7a and for transfer to a second conveyor belt 5.

Abstract: A method for cutting flexible formed shell product from a flexible plastic foam sheet. In the method, a foam shell formed in the sheet is drawn into and positioned in a die unit lower cavity and the die assembly is clamped together. A cutting die unit having dual curved serrated knife elements then descends and severs the formed shell from the sheet at all locations except for two short segments located at opposite ends of the formed shell. Then as a separate step, the partly severed formed shell is punched out from the flexible foam sheet, so as to provide multiple formed products. The products are usually formed as multiple units oriented in an end-to-end relationship in the foam sheet and which are simultaneously severed from the sheet. Cutting die apparatus adapted for cutting the formed products from the foam sheet is also disclosed.

Abstract: To prepare an existing buried main made from a material which is tough at ambient temperature for replacement by a new main of the same or a larger size via a mole device by fracturing the existing main by compressive and impact forces and by widening the bore for the insertion of the new main that is clamped to the mole device, a liquefied gas having as low a boiling point as possible at atmospheric pressure is sprayed against the conduit wall from a cooling carriage that is pulled through the existing main prior to the movement of the mole device therethrough, thereby cooling the existing main to a temperature causing low-temperature embrittlement of the material of the existing main.

Abstract: A rail segmenting machine for releasable attachment to the boom structure and hydraulic system of a hydraulic excavator. The present invention includes a frame consisting of rigid spaced apart plates that generally define a top end, an inlet end, a bottom end, an outlet end and an interior cavity. The top end of the frame is releasably secured to the boom structure and hydraulic system of the excavator and includes mounting ears extending outwardly therefrom adjacent the inlet end for swingable mounting of a hydraulically operated grapple thereto. A hydraulically operated notching arm is pivotally secured within the cavity of the frame and cooperates with an anvil secured to the bottom portion of the frame for producing a notch in a railroad rail extending therebetween. A hydraulically operated breaking head is mounted adjacent the outlet end of the frame and moves in a direction perpendicular to the extension of the rail exterior of the outlet end of the frame.

Abstract: An apparatus for replacing an existing buried pipe of a crackable, fracturable material. The apparatus has a fracturing structure which applies an intense local pressure to crack and fracture the existing buried pipe into irregular fragments. This fracturing structure can include one or a plurality of blades, some of which may be retractably and expandably movable. The structure which exerts the intense local pressure is also operable to effect at least some outward movement of the fragments. An expansion structure moves the fragments radially outwardly, generally about the axis of the existing main, to provide a passage for a replacement tubular assembly. The apparatus is moveable through the existing main by the action of either a pushing or a pulling force, and the pushing force may be applied by percussive action.

Abstract: A device for zig-zag folding a series of web segments connected at transverse lines of perforation and for separating a pre-determined series of the web segments into stacks having co-acting folding rolls adapted to deliver a zig-zag folded web, a pair of opposed cantilevered plates movably mounted adjacent the folding rolls to provide alternative support for a developing stack and to prevent concavity, and means for moving the plates.

Abstract: A shearing apparatus for breaking railroad type rails into small segments with a standard rail section including a base formed from a bottom flange on each side of the head connecting web. The apparatus includes a sequential rail feed mechanism comprised of an inclined vibratable supply table, a driven conveyor and means to move rails from the supply table to the conveyor. The rails are conveyed to an advancing mechanism located adjacent the breaker head assembly. Predetermined lengths of the conveyed rails are fed into the breaker head assembly where the rail is initially clamped. Following clamping, one bottom flange, on one side of the web, is sheared through and the rail is then contacted by a breaker head positioned beyond the shear plane established by the sheared flange.

Abstract: A pill cutter including a base member and a top member that is proportioned to receive therein the base member. The base member has therein a resilient pad which has a number of pill receiving pockets which are divided in half by a knife blade which is embedded within the resilient pad. The top member also contains a resilient pad. When the base and top members are pressed together, the pills in the pockets are pressed against the cutting edge of the cutting blades and are cut in half simultaneously. One end of the top member advantageously has its side walls formed in the shape of a scoop which can be used to dispense the pill halves into a container or the like.

Abstract: A tool has a hollow elongated body 10 made up of a leading section 12 attachable to a tow-cable by a clevis 28, an intermediate section 14 and a trailing section 20 housing a hydraulic cylinder 24 and attachable to a main liner 30. The intermediate section includes a frusto-conical wall in two parts 16 and 18, each of 180.degree. angular extent. The ram 24 operates a wedge 22 longitudinally to move the first part 16 outwardly or inwardly transversely of the body. The parts 16, 18 are slidably trapped to the wedge by slide components projecting into grooves. The tool is pulled by the two cable into the main with the part 16 retracted. Then the part 16 is moved outwardly to burst and enlarge the main, allowing the tool to advance further after retraction of the part 16. The parts 16, 18 each have an external longitudinal rib 68, 70. The part 16 has longitudinal marginal extensions overlapping the longitudinal margins of the part 18.