Abstract: The present invention discloses a Fluid End and its manufacturing method. The conventional fluid end manufacturing methods involve machining of all surfaces. This demands more input stock for manufacturing process and a lot of material wastage during machining process. In the conventional processes involving open die forging followed by machining result into only about 34% utilization of material. In the present invention, fluid end component geometry is optimized. Assembly surfaces are machined whereas other or non-assembly surfaces are as-forged condition. The method of invention also results in significant reduction in machining time and chip removal. The present invention also discloses a process of manufacturing using a combination of open die and closed die forging, and machining.

Abstract: The present invention seeks to enable a band-shaped metal wire member to be stably accommodated within a die. A die is prepared that includes a bottom die provided with a depression and a top die provided with a projection that can be arranged within the depression so as to close off a space above the depression. An inner surface of the depression includes a central die surface formed at a width-direction center of a base of the depression and a pair of curved guide die surfaces provided continuous with two sides of the central die surface and curved so as to project outward. The central die surface is formed as a flat surface or as a surface that curves more gently than the pair of curved guide die surfaces. A bonding process portion of a band-shaped metal wire member is folded in two and arranged within the depression.

Abstract: Heat exchangers are manufactured by three-dimensional (3D) printers by printing subsequent layers of a material in a print direction. The heat exchangers include one or more tubes. The one or more tubes are configured to transport a fluid to be heated or cooled. Each of the one or more tubes defines a slope that is within a threshold angle of the print direction. The heat exchangers include a plurality of fins that are each configured to intersect with the one or more tubes while allowing fluid flow between the plurality of fins to heat or cool the fluid. Each fin of the plurality of fins defines a slope that is within a threshold angle of the print direction.

Abstract: A die set for bending work pieces using a power crimping tool, the die set including a first die including a first inside surface and a second inside surface angled a predetermined number of degrees relative to the first surface and a second die including an inside surface corresponding to the first inside surface of the first die and an inside surface corresponding to the second inside surface of the first die.

Abstract: A side panel including a first member and a second member having a higher strength is manufactured by arranging a corner portion of the second member in a recessed portion of the first member, and by simultaneously press-working the first member and the second member.

Abstract: A method of manufacturing a crankshaft comprising providing two parts, each part comprising two webs, a portion of a crank journal and a portion of a main journal, welding the two portions of the crank journal together, heating the crank journal, inserting a shim between the webs, and upset forging to reduce the length of the crank journal to form a forged segment. Alternatively, the portions of the main journal may be welded, heated, shimmed, and forged to form a forged segment. The crankshaft may be lengthened by adding additional parts or forged segments using the same steps. A production line for carrying out this method when producing a crankshaft with n number of crank journals, where n is an even integer.

Abstract: The invention provides methods for making bunters used to form headstamp indicia into ammunition cases. The invention also provides bunter blanks that are specially configured to yield high quality bunters.

Abstract: Provided are a bending die having surface microstructures and a bending punch thereof applicable to stamping processing to bend a blank to form a shape. The bending die includes a lower die, an upper die, and a workpiece placing piece. The lower die includes a die, and the die includes a forming surface. The upper die includes a bending punch, the bending punch stamps a blank placed on the die in a back and forth stroke, and the bending punch includes a working portion coming into contact with the blank during stamping. The workpiece placing piece is disposed between the upper die and the lower die and used to position or/and press the blank placed on the die. A plurality of microstructures are disposed on the forming surface and/or on the surface of the working portion.

Abstract: Provided are a bending die having surface microstructures and a bending punch thereof applicable to stamping processing to bend a blank to form a shape. The bending die includes a lower die, an upper die, and a workpiece placing piece. The lower die includes a die, and the die includes a forming surface. The upper die includes a bending punch, the bending punch stamps a blank placed on the die in a back and forth stroke, and the bending punch includes a working portion coming into contact with the blank during stamping. The workpiece placing piece is disposed between the upper die and the lower die and used to position or/and press the blank placed on the die. A plurality of microstructures are disposed on the forming surface and/or on the surface of the working portion.

Abstract: The present invention relates to a B-shaped crimping die for a crimping tool. The crimping tool and the crimping die are used for crimping a plug with an electrical cable located therein into a B-shape. The crimping die comprises a first crimping die half and a second crimping die half. A B-shaped crimping contour is defined by the crimping die halves in a closed state. A first crimping contour part of the first crimping die half and a second crimping contour part of the second crimping die half together build the crimping contour. Two transition points are located at the transitions between the two crimping contour parts. According to the invention an opening angle of a contour of the second crimping die half increases at said transition points in moving direction of the first crimping die half during the crimping process.

Abstract: A method of bending a tube arrangement including an inner tube disposed within an outer tube is performed using a bending die having a concave groove including a curved portion extending around a peripheral surface of the bending die, the curved portion of the concave groove having at least one ridge projecting therefrom. The tube arrangement is located within the concave groove and a force is applied to the tube arrangement in a direction toward the curved portion of the bending die to cause the tube arrangement to conform to the shape of the concave groove. The at least one ridge projecting from the concave groove causes the outer tube to deform such that an interior surface of the outer tube contacts an exterior surface of the inner tube, securing a position of the inner tube within the outer tube.

Abstract: An improved heat sink comprises a plurality of wire fins mounted on a heat sink base. Each wire fin comprises a coil made up of a plurality of contiguous loops of wire. A wire fin can be manufactured by deforming a helical wire member to an elongate, relatively compact shape. Several such wire fins can then be mounted to a heat sink base in order to form a pin-fin type heat sink.

Abstract: A sheet material processing apparatus has a pressurizing part of a sheet material and a supporting part of the pressurized sheet material. The apparatus includes an end face pressing upper press die that receives a pressurizing force, an end face pressing lower press die that is arranged on the supporting part and faces the end face pressing upper press die so that an end face of the sheet material is inserted between the end face pressing upper and lower press dies, an end face pressing part that, with the end face pressing upper press die being moved toward the end face pressing lower press die, presses the end face of the sheet material, and an end face pressing width adjusting part that sets a pressing width of the end face of the sheet material.

Abstract: A pressing terminal includes an outer conductive member having a shield outer tube; an inner conductive member; and a dielectric member. The dielectric member includes a protruding portion fitted into the shield outer tube so that a signal line pressing portion of the inner conductive member is situated at a pressing tool insertion opening portion. The dielectric member is inserted into a shield outer tube with the protruding portion thereof sliding against the shield outer tube. A terminal pressing device includes an anvil unit and a crimper unit. Upon attaching the signal wire, a claw portion of a signal line crimper of the crimper unit is inserted into a claw insertion groove portion of a signal line anvil of the anvil unit. A terminal pressing anvil portion of the signal line anvil is ushered to a terminal pressing anvil insertion portion of the signal line crimper.

Abstract: Device for machining indentations in headrest tubes, comprising a support matrix that holds a tube in order to make indentations in it, positioned on a press that exerts a pressure on said matrix in a vertical direction such that the tube is rigidly secure in the support matrix. In addition, the device has a roller holder in which can turn freely at least one form roller, connected by an arm to a vertical displacement mechanism formed by a motor, an eccentric piece and a connecting rod, such that the roller can move up and down. In addition, a motor is coupled through a spindle to the assembly formed by the support matrix and the press, allowing it to move horizontally.

Abstract: A pair of pliers including an upper jaw, a lower jaw, two handles, and a pivot. The upper jaw and the lower jaw combine to form a gripping jaw capable of opening and closing. The upper jaw is in the shape of an inner arc, and the lower jaw is in the shape of an outer arc. The inner arc includes a concave hole, and the outer arc includes a convex member corresponding to the concave hole. The two handles are integrated with the upper jaw and the lower jaw, respectively, and fixed via the pivot to form a cross connection.

Abstract: Multiple movable die portions (press punches) are respectively opposing to multiple fixed die portions (block members). Each of the press punches is sequentially pushed down with a predetermined time difference to the corresponding block member to continuously carry out press work to a material inserted into a press-work area between the press punches and the block members. A clearance is formed between a forward end of the press punch and a forward end of the block member at a position shortly before a press-work operating position in order to control a pulling force of the material, so that a shape distortion can be avoided.

Abstract: A method for assembling a part of a metal material and a part of a composite material, the junction of the two parts being achieved through a fastener having a substantially constant section and received in a first hole formed in the part of a metal material and a second hole formed in the part of a composite material. According to the disclosed embodiments and before assembling the aforementioned parts, the method includes: an expansion step for generating a field of compression stresses at the periphery of the first hole and locally in the material constituting the part of a metal material using an expansion tool; a single boring step for making the first hole and the second hole with a diameter Øfinal substantially larger than the diameter of the fastener in order to leave a gap between the inner walls of the holes and the outer surface of the fastener; and an assembling step for placing the fastener inside the holes for maintaining together the metal part and the composite part.

Abstract: A thrust dynamic pressure pattern is marked on a rotating member or fixed member set on a rest table. A pressure for marking is applied to a member to be marked in a cycle of applying and releasing the pressure, and a supplemental force for keeping the member to be marked, still is separately applied. According to the present embodiment, a rotating device can be provided that narrows down a bearing gap and improves the efficiency of raking up a lubricant so as to increase the dynamic pressure by reducing the deformation of the shape of the protrusions of a thrust dynamic pressure pattern and the variation in the height of the protrusions when forming the thrust dynamic pressure pattern in a method of producing a rotating device.

Abstract: A crimper die set for assembling a safety hose sleeve system includes an upper die comprising an upper curved compressive face, upper recess walls extending contiguous from the upper compressive face at an acute angel to the upper compressive face, each defining a portion of a cavity Thrust plate slots extend upward from ends of the upper recess walls. A lower die comprises a lower curved compressive face, lower recess walls extend contiguous from the lower compressive face at an acute angel to the lower compressive face and define another portion of each cavity. Lower thrust plate slots extend downward from an end of the lower recess walls, distal from the lower compressive face. Thrust plates extend from the lower thrust plate slot into the upper thrust plate slot, across the cavity at an acute angle to each of the recess walls, defining an outer abutment of the cavity.

Abstract: A die for use in a sheet metal forming process includes a die material having a surface. A plurality of depressions is formed in a predetermined portion of the surface, where each of the plurality of depressions has a predetermined diameter and depth. Interaction of a surface of a sheet metal blank with i) the plurality of depressions, and ii) a solid forming lubricant, including particles of an average predetermined size and distribution, disposed on one of the die material surface or the sheet metal blank surface substantially reduces adhesion between the sheet metal blank surface and the die material surface during the sheet metal forming process.

Abstract: An oil-pressure swaging tool for rebuilding a connecting pipe includes an abutting member abutting against an oil-pressure device, a connector inserted into a connecting pipe, one end of a first axial member passing through the abutting member to connect to one end of the connector, another end of the first axial member connected to the oil-pressure device, a rebuilding member assembled to another end of the connecting pipe, a pressure collar adjacent to one end of the rebuilding member, one end of a second axial member passing through the rebuilding member to connected to the pressure collar, another end of the second axial member connected to another end of the connector. Therefore, when the opening of the connecting pipe is rebuilt by the oil-pressure swaging tool of the present invention, one end of the connecting pipe is not necessary to abut against a wall because of the abutting member.

Abstract: [Problem] There is provided a pipe end shape correcting apparatus capable of improving the roundness without loss of work efficiency and the mechanical damage to a weld bead even in the case where the pipe ends of UOE metal pipes having various outside diameters are worked.

Abstract: A hand and mechanically activated rivet setting device uniquely and integrally designed to set multiple different types of rivets comprising tubular, semi-tubular and solid rivets made entirely or in part from aluminum, brass, steel and stainless steel having multiple different kinds of heads comprising truss, dome and flat rivet heads; in a work product consisting of pieces and components to be riveted together. The device has the means to set rivets from different positional locations within the device and provides the device operator the ability to completely control the rivet setting process, assuring precision rivet setting without damaging the pieces or components being riveted.

Abstract: A manufacturing method of the present invention includes the steps of: preparing a pre-line forming member having no face line; and cutting the pre-line forming member using a cutter 12 to form the face line on the pre-line forming member. The cutter 8 has a tip part having a cutting surface. The cutting surface has a recessed curved surface c4. An edge of the face line 8 is cut by the recessed curved surface c4. Preferably, the step of cutting is carried out by axial rotation of the cutter 8. Preferably, the cutting surface has a plane part c5 formed on an upper side of the recessed curved surface c4. Preferably, the upper side plane part c5 is perpendicular to a rotation axis rz of the cutter 12. Preferably, the cutting surface has a conical surface Fc formed on a lower side of the recessed curved surface c4.

Abstract: An apparatus and method for forming a style line with a sharp radius in a metal with lower formability than that of mild steel is disclosed. The apparatus and method use a die set with a means to back a portion of the metal having the style line formed with a material that moves with the surface of the style line as it is formed. In one embodiment an elastic member backs the metal panel, and in another embodiment a fluid medium backs the metal panel where the style line is formed. The apparatus and method achieve sharper radius style lines in metals like aluminum, advanced high strength steel, and ultra-high strength steel than a traditional hard surface die set can achieve.

Abstract: The present invention relates to a B-shaped crimping die for a crimping tool. The crimping tool and the crimping die are used for crimping a plug with an electrical cable located therein into a B-shape. The crimping die comprises a first crimping die half and a second crimping die half. A B-shaped crimping contour is defined by the crimping die halves in a closed state. A first crimping contour part of the first crimping die half and a second crimping contour part of the second crimping die half together build the crimping contour. Two transition points are located at the transitions between the two crimping contour parts. According to the invention an opening angle of a contour of the second crimping die half increases at said transition points in moving direction of the first crimping die half during the crimping process.

Abstract: A crimp tool and crimp arrangement for connecting a clip onto a snowmobile tread. The snowmobile tread and clip once connected together are positioned in cooperating engagement with the suspension of a snowmobile. The crimp tool implements a pneumatic actuator having a shaft with a transverse axle that is in operable engagement with bearing surfaces of the two press levers. The transverse axle causes the two press levers to pivot about pivot posts between a crimped and uncrimped position. When a clip for connection to the tread of the snowmobile is positioned between the crimp ends of the two press levers, the clip can be bent from an uncrimped position to a crimped position by the crimp ends, thereby connecting the clip to the tread of the snowmobile.

Abstract: A coupling for joining plan end pipe having a housing made from a casting with a pocket disposed in the casting. The pockets holds an insert that engages the plain end pipe, and the insert is secured to the housing without the use of machined features on the housing or the use of additional components or adhesives to secure the insert to the housing. In a preferred embodiment, each insert is disposed in a pocket on the inner surface of the coupling assembly, with projections extending from the inner surface disposed within cavities on opposing sides of each insert to retain the insert within the pocket by obstructing the opening to the pocket. A preferred device and method of forming the projections is a press that deforms the projections to retain the inserts in the pockets.

Abstract: Disclosed is a method of forming a heat exchanger turbulizer apparatus including a member having a longitudinal axis, a lateral width and a plurality of strips including first strips and second strips, each strip extending widthwise and being corrugated longitudinally so as to form a plurality of laterally spaced-apart sections connected to one another by bridges projecting from the sections in a common direction, the bridges of the first and second strips extending in the same direction and the corrugations of the second strips being offset laterally from the corrugations of the first strips. The method comprises: crimping longitudinally-corrugated strip material between first and second forming dies to form said apparatus, said dies being adapted such that substantially all lateral movement of strip material in crimping results from strip material being drawn laterally by material that has been displaced in a direction parallel to the direction of die movement.

Abstract: A system for forming different types of clamshell components including a moveable base, a stationary base, and a squeezer assembly capable of accommodating different types of clamshell components having different lengths, shapes, locations of piercings. The squeezer assembly includes interchangeable squeezer elements. To switch between forming a first type of clamshell component and a second type of clamshell component, one of the two bases is moved relative to the other of the two bases and/or squeezer units for forming the first type of clamshell component are replaced with squeezer units for forming the second type of clamshell component. Reconfiguring the bases and interchanging the squeezers of a clamshell tool, instead of replacing an entire clamshell tool with a different clamshell tool, minimizes lost productivity time, reduces capital costs, and eliminates the problem of storing several different clamshell assembly tools.

Abstract: A guided keeper and method for metal forming dies includes a base with a head portion and an opposite externally threaded mounting portion received in a mating die aperture. A scalloped shoulder portion with arc-shaped notches is located axially between the head and the mounting portions of the base, and a retainer ring groove is located axially between the head and the scalloped shoulder portion of the base. A cap screw is retained in the die, and has a cylindrical head received in one of the arc-shaped notches in the base to retain the base in place. A retainer ring is mounted in the ring groove in the base and retains the cap screw in place.

Abstract: A method of making metal target blank using circular groove pressing includes pressing a metal or metal alloy target blank in a first circular grooved pressing die set into a first concentric corrugated shape while maintaining an original diameter of the target blank to create concentric rings of shear deformation in the target blank. Forces are then applied to the concentric corrugated target blank sufficient to substantially flatten the target blank with a flat die set while maintaining the original diameter of the target blank to restore the target blank to a substantially flat condition. The target blank is pressed in a second circular grooved die set into a second concentric corrugated shape while maintaining the original diameter of the target blank, wherein the second die set has a groove pattern offset from a groove pattern of the first die set so as to create concentric rings of shear deformation in areas of the target blank which were not previously deformed.

Abstract: A hydraulic crimping tool crimping die including a first section adapted to be removably connected to a die mounting area of a hydraulic crimping tool, and a second section forming a crimping surface adapted to crimp a connector onto a conductor. The crimping die comprises an electrically non-conductive material adapted to prevent electrical arcing with the crimping die.

Abstract: The present invention provides a production apparatus for crankshaft, including: a die which has a lower die, an upper die, and plural side forming punches, the upper die being provided movably to the lower die, the side forming punches moving perpendicularly to a movement direction of the upper die; a press ram which moves the upper die to the lower die, closes a material of the crankshaft, and forms the material; cam mechanisms which are provided for the side forming punches and which move the side forming punches to an inside portion of the die in accordance with movement of the press ram; a grade separation structure which is provided to at least one of the side forming punches in order to prevent interference of the side forming punches with each other.

Abstract: A die set adapted to remove an end of a substantially flat lug of an electrical connector. The die set includes a first die and a second die. The first die includes a first frame and a spring loaded member connected to the first frame. The first frame includes a first contact surface adapted to directly contact a first side of the lug. The second die includes a second frame having a second contact surface adapted to contact a second side of the lug at a position offset from the first contact surface. The spring loaded member is adapted to contact the first side of the lug directly opposite the second contact surface. The first and second contact surfaces are adapted to shear off the end of the lug from the electrical connector.

Abstract: The invention involves a forming tool for a machine tool. The forming tool can be used, for example, to create various large forms in sheet metal or other workpieces.

Abstract: A pressing device for forming steel sheet blanks into clips, which comprise curved planking elements and rectilinear stringer elements for connecting a fuselage cell skin to a stringer and to an annular rib in an aircraft fuselage, comprises at least one curved upper tool, at least one curved lower tool, at least one rectilinear upper tool, and at least one rectilinear lower tool. A steel sheet blank is receivable and formable between the at least one curved upper and lower tools and the at least one rectilinear upper and lower tools. The at least one curved upper and lower tool each comprises an upper and lower convexity surface designed to essentially correspond to each other in order to form the curved planking element in a single stroke surface model forming process by simultaneously bending and stamping.

Abstract: A die for use in a sheet metal forming process includes a die material having a surface. A plurality of depressions is formed in a predetermined portion of the surface, where each of the plurality of depressions has a predetermined diameter and depth. Interaction of a surface of a sheet metal blank with i) the plurality of depressions, and ii) a solid forming lubricant, including particles of an average predetermined size and distribution, disposed on one of the die material surface or the sheet metal blank surface substantially reduces adhesion between the sheet metal blank surface and the die material surface during the sheet metal forming process.

Abstract: The present invention is directed to a golf club head, and a method of making the golf club head, with an improved striking surface. The grooves are formed in the strike surface with tight tolerances. The grooves may contain a plurality of portions, including a radiused or angled portion, a portion having substantially parallel walls, and a portion having a v-shape.

Abstract: A method for producing low-springback half shells made of a metal, in particular steel or a steel alloy, includes drawing in at least one drawing die a blank, such that the blanks have flange regions on the deep drawn body after the deep drawing. The flange regions are shaped by upsetting a corner substantially perpendicularly to a wall of the deep drawn region of the blank and the flange regions are subsequently trimmed in a shearing die, such that half shells without margins are produced.

Abstract: A method for fixation of a jack to a panel or bracket of an electronics module. A jack having an encircling flange is machined to include a barrel having at least one longitudinal knurl and an inwardly-tapered interior section. A swaging tool includes a body having a lower surface with an open circular channel arranged to circumscribe the circular open end of the barrel of the jack. The jack is fixed to a circular port within the panel by inserting the jack into the port so that the flange contacts a surface of the panel and then applying a downward-acting force onto the swaging tool aligned with open end of the barrel to compressively fix the jack to the panel.

Abstract: A method of forming a chamfered through hole having a chamfered portion at each end thereof by: forming a prepared hole in a plate-like portion; forming a first chamfered portion by driving a first punch; forming a second chamfered portion by driving a second punch, which has a second tapered surface and a generally columnar central pressing portion protruding from the center of the second tapered surface and having an annular corner at a tip thereof, and thereby forming the second chamfered portion and a central recess recessed axially inward; and punching out an unnecessary portion protruding radially inward of the prepared hole by using a finishing punch having an outer diameter equal to or smaller than that of the corner of the central pressing portion. The punching out the unnecessary portion is performed by punching from the first chamfered portion toward the second chamfered portion using the finishing punch.

Abstract: A piece of equipment for production of a closed-section cross-member configured to connect two longitudinal arms of a flexible axle of a motor vehicle. The equipment includes at least one matrix configured to cooperate with a punch to form a torsion area of a certain length on the closed section of the cross-member and a mechanism to maintain the cross-member in position. The length of the matrix and/or the punch can be adapted to adapt the length of the torsion area.

Abstract: An electrical connector crimp die including a main body and an indicia forming section. The main body has a connector contacting surface between opposite ends of the main body. The indicia forming section is on the connector contacting surface. When the crimp die forms a crimp on an electrical connector, the indicia forming section is adapted to form an alignment indicia on the electrical connector for subsequent alignment of the die with the crimp to form a subsequent overlapping crimp.

Abstract: A multi-functional crimping tool for connecting pipe joints with pipes is disclosed, the tool includes a pair of crimping head hinged together, form a circle cavity for penetrating the pipe, and at least a capped screw rotatably mounted onto a top side of the crimping head body and shifted from a fastening position and a releasing position; a pair of crimping jaws respectively and operatively clipped onto the crimping heads respectively, wherein in the fastening position, the capped screw is screwed down to secure the crimping jaws attach onto said crimping heads, and in the releasing position, the capped screw is loosened up allowing the crimping jaws transversely pulled off the crimping head for convenient replacement.

Abstract: An electrical connector crimping tool head including a frame, a ram and a connector locator. The frame includes a first mounting area adapted to removably receive a first connector crimping die. The ram is movably connected to the frame. The ram includes a second mounting area adapted to removably receive a second connector crimping die. The connector locator is on the frame and is adapted to indicate proper positioning of an electrical connector relative to the frame for subsequent crimping by the first and second connector crimping dies.

Abstract: A method for fixation of a jack to a panel or bracket of an electronics module. A jack having an encircling flange is machined to include a barrel having at least one longitudinal knurl and an inwardly-tapered interior section. A swaging tool includes a body having a lower surface with an open circular channel arranged to circumscribe the circular open end of the barrel of the jack. The jack is fixed to a circular port within the panel by inserting the jack into the port so that the flange contacts a surface of the panel and then applying a downward-acting force onto the swaging tool aligned with open end of the barrel to compressively fix the jack to the panel.

Abstract: A device for contamination-free sealing of a tube having a collar positioned thereon. The device can include a first jaw portion and a second jaw portion. The first jaw portion can include two pressing bars extending outwardly therefrom, and a pressing piece extending outwardly therefrom. The pressing piece can include a substantially flat surface, and can be positioned between the pressing bars. The pressing bars each have a pressing surface. The second jaw portion can include a support surface. Each of the pressing surfaces can be substantially flat. When the first jaw portion is moved toward the second jaw portion, each of the two pressing bars contacts the collar proximate an end portion of the collar, and the pressing piece contacts the collar proximate a center portion of the collar.

Abstract: A press-connecting head of a pair of press-connecting pliers for connecting a coaxial terminal, it is composed of an inserting/retracting member and two pressing dies respectively provided on two mutually opposite sides of the inserting/retracting member; wherein the inserting/retracting member is assembled with the press-connecting pliers by an inserting mode, hence by a simple action of inserting/retracting, different pressing dies of the same press-connecting head can be mutually changed to be exactly aligned with a fixed block, or the press-connecting head can be changed for another one with pressing dies of other specifications. And then the press-connecting pliers using the press-connecting head structure can allow execution of press-connecting operation of the coaxial terminals of different specifications with a coaxial signal line; thus the range of application of the press-connecting pliers can be enlarged.