阅读说明：本技术 一种用于管件配套的挤压钳 (Extrusion pliers matched with pipe fitting ) 是由 都昌林 于 2021-03-12 设计创作，主要内容包括：本发明公开了一种用于管件配套的挤压钳,属于建设管道工程领域。该挤压钳包括三个彼此配合的钳夹、两个彼此对应的钳柄、用于将两个钳柄相连接的连接件、V型弹簧和动力装置；所述钳夹由钳夹外壳和装在钳外壳内的磨头组成,所述磨头的内壁上有凸起的凸筋。挤压时,三段磨头对接,其内壁构成一个圆柱形的管件容纳区域。通过本发明,可以实施对薄壁带筋管件、钢塑复合管件、管件及套在其上的外套管件的挤压,尤其是对后二种进行挤压时,能够让管件与其塑造层、管件与外套管均产生均匀的变形,从而使内外管件牢固地连接在一起,很好的解决了薄壁管件、钢塑管件、管件与外套管连接时的不可靠、变形、漏水等问题。(The invention discloses an extrusion clamp matched with a pipe fitting, and belongs to the field of pipeline construction engineering. The squeezing pliers comprise three mutually matched pliers jaws, two mutually corresponding pliers handles, a connecting piece for connecting the two pliers handles, a V-shaped spring and a power device; the forceps holder consists of a forceps holder shell and a grinding head arranged in the forceps holder shell, and a convex rib is arranged on the inner wall of the grinding head. When the three sections of grinding heads are in butt joint during extrusion, the inner walls of the three sections of grinding heads form a cylindrical pipe fitting accommodating area. The invention can extrude the thin-wall ribbed pipe, the steel-plastic composite pipe, the pipe and the outer sleeve pipe sleeved on the pipe, and particularly can ensure that the pipe, the molding layer of the pipe, the pipe and the outer sleeve pipe are uniformly deformed when the latter two pipes are extruded, so that the inner pipe and the outer pipe are firmly connected together, and the problems of unreliability, deformation, water leakage and the like when the thin-wall pipe, the steel-plastic pipe and the pipe are connected with the outer sleeve pipe are well solved.)

1. The extrusion pliers matched with the pipe fitting are characterized by comprising three mutually matched pliers jaws, two mutually corresponding pliers handles, a connecting piece (6) used for connecting the two pliers handles, a V-shaped spring (17) and a power device; the forceps holder consists of a forceps holder shell and a grinding head arranged in the forceps holder shell, and a convex rib (10) is arranged on the inner wall of the grinding head;

taking the axis of the pipe fitting as a Z axis and the cross section of the pipe fitting as a reference surface, respectively marking three mutually matched jaws as a left jaw (1), a right jaw (2) and an upper jaw (3) according to the positions of the three mutually matched jaws on the reference surface, and respectively marking two mutually corresponding jaw handles as a left jaw handle (4) and a right jaw handle (5) according to the positions of the two mutually corresponding jaw handles on the reference surface;

the forceps holder shell corresponding to the upper forceps holder (3) is marked as an upper forceps holder shell (13), the forceps holder shells corresponding to the left forceps holder (1) and the right forceps holder (2) are marked as side forceps holder shells (12), the two sections of the side forceps holder shells (12) have the same structure and correspond to each other left and right, the shapes of the upper forceps holder shells (13) and the side forceps holder shells (12) on a reference plane are both partial circular rings, an upper grinding head (7) is arranged on the inner side of the upper forceps holder shell (13), and two side grinding heads (8) are respectively arranged on the inner sides of the left and right side forceps holder shells (12); the state of the extrusion pliers when extruding the pipe fitting is called as a working state, when the pipe fitting is in the working state, a circular ring is formed on a reference surface by the left side clamp shell (12), the right side clamp shell (12) and the upper clamp shell (13), the inner walls of three grinding heads in the three clamp shells form a circular pipe fitting accommodating area (11) on the reference surface, wherein the arc lengths of the inner walls of two side grinding heads (8) in the pipe fitting accommodating area (11) are the same, and the left side and the right side of the inner walls of the two side grinding heads are completely corresponding;

the upper jaw shell (13) consists of 2 upper shell pieces (16) with the same shape, the side jaw shell (12) consists of 3 side shell pieces (15) with the same shape, the connecting side of each side shell piece (15) and each upper shell piece (16) is marked as an upper side, and the other side of each side shell piece is marked as a lower side; the cross section of each shell piece on the reference surface is a partial circular ring, and through holes (9) are formed in the two sides of each shell piece; after aligning 2 upper shell pieces (16) along the Z-axis direction, respectively inserting the upper parts of the left side and the right side into two shell piece gaps formed by clamping 3 side shell pieces (15) in the left side and the right side clamp shells (12), aligning through holes (9) at the inserting positions, then penetrating the through holes (9) by using pins (14), and locking the matching positions of the pins (14) and the side shell pieces (15) by using snap springs (24) to complete the connection of the two side clamp shells (12) and the upper clamp shell (13);

the through holes (9) on the lower sides of three side shell pieces (15) in the right forceps holder (2) are aligned and then locked through pins (14) and clamp springs (24), and the distance between every two side shell pieces (15) is kept between one upper shell piece (16), namely, the pins (14) form a transverse shaft which is divided into two sections by the three side shell pieces (15) at the lower part of the right forceps holder (2), the upper part of the right forceps holder (5) is made into a hook (21) corresponding to the transverse shaft, when the forceps holder is in an operating state, the hook (21) is hooked on the transverse shaft, the connection between the right forceps holder (5) and the right forceps holder (2) is completed, and a pipe fitting accommodating area (11) is completed, when the forceps holder is not in the operating state, the hook (21) is separated from the transverse shaft, and the forceps holder (5) is separated from the right forceps holder (2); the upper part of the left forceps handle (4) is provided with a through hole (9), after the through hole (9) is aligned with the through holes (9) on the lower sides of the three shell pieces (15) in the left forceps holder (1), the left forceps handle (4) is locked by a pin (14) and a clamp spring (24), and the connection between the left forceps handle (4) and the left forceps holder (1) is completed;

a spring groove (30) extending along the Z-axis direction is respectively formed in the middle of the right end face of the left forceps handle (4) and the middle of the left end face of the right forceps handle (5), a V-shaped spring (17) is arranged in a space formed by the two spring grooves (30), and two spring feet (31) which are forked towards the left and right directions are inserted between the right end face of the left forceps handle (4) and the left end face of the right forceps handle (5) below the spring grooves (30); a clamping groove (19) extending along the Z-axis direction is formed in the right end face of the left forceps handle (4) above the spring groove (30), a protrusion (20) corresponding to the clamping groove (19) is arranged on the left end face of the right forceps handle (5), and the protrusion (20) is embedded into the clamping groove (19) in a working state; the connecting piece (6) is T-shaped, the left forceps handle (4) and the right forceps handle (5) are placed between the two connecting pieces (6), and two sides of the upper parts of the two connecting pieces (6) are respectively hinged with the left forceps handle (4) and the right forceps handle (5); after the two connecting pieces (6) are hinged with the left and right clamp handles, the positions of the clamping grooves (19) and the protrusions (20) are taken as swing centers, the left and right clamp handles form a scissor head, namely the left and right clamp handles can be opened and closed like scissors, and the swing amplitude and the reset are controlled by a V-shaped spring (17);

recording the distance from the center of the spring groove (30) to the upper end face of the left forceps handle (4) as A1, taking the distance A2 downwards from the spring groove (30) on the right end face of the left forceps handle (4) to obtain a point a1, taking the distance A2 downwards from the spring groove (30) on the left end face of the right forceps handle (5) to obtain a point a2, and gradually inclining the right end face of the left forceps handle (4) and the left end face of the right forceps handle (5) towards two sides respectively from the points a1 and a2, namely forming a bottom consisting of two arcs between the right end face of the left forceps handle (4) and the left end face of the right forceps handle (5); a2 ═ 0.7-1.2a 1;

and a power connecting hole (18) is reserved at the lower part of the connecting piece (6), the power connecting hole (18) is connected with a power device, and when the pipe fitting is in a working state, an extrusion head (25) in the power device is driven by power to apply upward acting force to the bottom formed by the left forceps handle (4) and the right forceps handle (5) from bottom to top so as to extrude the pipe fitting.

2. The pair of squeeze pliers for pipe fittings according to claim 1, wherein the number of the ribs (10) is 2-4, and the width and the depth of each rib (10) are 1mm-4 mm.

3. The extrusion pliers for pipe fittings of claim 1, wherein the upper grinding head (7) and the side grinding head (8) are replaceable sequential products.

4. The squeeze pliers matched with a pipe fitting according to claim 1, wherein the upper jaw housing (13) further comprises two outer clamping pieces (22), the cross section of each outer clamping piece (22) is a partial circular ring, and the two outer clamping pieces (22) are fixedly connected to the outer sides of the two upper housing pieces (16) through bolts (23) respectively to reinforce the upper jaw (4).

5. The matched extrusion pliers of claim 1, wherein the grinding head is made of heat-treated die steel.

Technical Field

The invention relates to the field of pipeline construction engineering, in particular to an extrusion clamp matched with a pipe fitting.

Background

At present, a considerable part of acoustic pipes and grouting pipes for foundation pile detection are thin-wall steel pipe acoustic pipes with the wall thickness of 1.0 mm to 2.0 mm. In order to ensure that the connection is watertight, the outer connecting pipe protrudes outwards by two ribs, and a sealing ring is arranged in each rib. For the pipe fitting, the common method at present adopts a hydraulic clamp with a groove to extrude the pipe fitting for connection, the water leakage performance is better after the connection, but the drawing performance is poorer, and two sections of pipes are easy to separate in the hoisting process, so the quality is seriously influenced.

Recently, a steel-plastic composite sounding pipe is developed, wherein a layer of plastic is compounded outside the steel pipe, the plastic layer has the function of a sealing ring, and an outer sleeve is adopted for connecting two steel-plastic sounding pipes. When the pipe fitting is constructed, if the hydraulic pliers are used for extrusion, the sealing ring can deform, the water stopping effect is good, but the pulling resistance is insufficient, and the joint connection of the sound measuring pipe definitely requires the pulling force to be more than 3000N. And moreover, the hydraulic pliers which are extruded up and down are two arcs, and when the hydraulic pliers are extruded up and down, the sleeve is extruded up and down by two ribs at the joint of the upper grinding head and the lower grinding head, so that the appearance effect is influenced, and the hidden danger of water leakage is easily caused.

Therefore, how to develop an extrusion convenience, can be according to different pipe diameters, adopt the extrusion die that can tear open and trade, increase the extrusion force, make interior outer pipe fitting and plastics all produce same deformation, make plastics realize the extrusion, play the effect of sealing washer to both reach the purpose of stagnant water, have more than 3000N drawing force hydraulic tong again, be the technical problem that needs to solve urgently.

The invention content is as follows:

the technical problem to be solved by the invention is as follows: overcomes the problems in the prior art, and provides the extrusion pliers which have reasonable structure, convenient extrusion, firm pipe connection, low cost and repeated use.

The object of the invention is thus achieved. The invention provides a pair of extrusion pliers matched with a pipe fitting, which comprises three mutually matched pliers jaws, two mutually corresponding pliers handles, a connecting piece for connecting the two pliers handles, a V-shaped spring and a power device, wherein the two pliers handles are matched with each other; the forceps holder consists of a forceps holder shell and a grinding head arranged in the forceps holder shell, and a convex rib is arranged on the inner wall of the grinding head;

taking the axis of the pipe fitting as a Z axis and the cross section of the pipe fitting as a reference surface, respectively marking three mutually matched jaws as a left jaw, a right jaw and an upper jaw according to the positions of the three mutually matched jaws on the reference surface, and respectively marking two mutually corresponding jaw handles as a left jaw handle and a right jaw handle according to the positions of the two mutually corresponding jaw handles on the reference surface;

the forceps holder shell corresponding to the upper forceps holder is marked as an upper forceps holder shell, the forceps holder shells corresponding to the left forceps holder 1 and the right forceps holder 2 are marked as side forceps holder shells, the two sections of the side forceps holder shells have the same structure and correspond to each other left and right, the shapes of the upper forceps holder shell and the side forceps holder shells on a reference surface are both partial circular rings, an upper grinding head is arranged on the inner side of the upper forceps holder shell, and two side grinding heads are respectively arranged on the inner sides of the left and right side forceps holder shell; the state of the extrusion pliers when extruding the pipe fitting is called as a working state, and in the working state, the left side clamp shell, the right side clamp shell and the upper clamp shell form a circular ring on a reference surface, and the inner walls of three sections of grinding heads in the three sections of clamp shells form a circular pipe fitting accommodating area 11 on the reference surface, wherein the arc lengths of the inner walls of the two side grinding heads in the pipe fitting accommodating area are the same and the two side grinding heads completely correspond to each other left and right;

the upper forceps holder shell consists of 2 upper shell pieces with the same shape, the side forceps holder shell consists of 3 side shell pieces with the same shape, the connecting side of each side shell piece and the upper shell piece is marked as an upper side, and the other side of each side shell piece is marked as a lower side; the cross section of each shell piece on the reference surface is a partial circular ring, and through holes are formed in the two sides of each shell piece; after aligning 2 upper shell pieces along the Z-axis direction, respectively inserting the upper parts of the left side and the right side into two shell piece gaps formed by clamping 3 side shell pieces in the left side and the right side forceps shell, aligning through holes at the inserting positions, then penetrating through the through holes by pins, and locking the matching positions of the pins and the side shell pieces by snap springs to complete the connection of the two side forceps shells and the upper forceps shell;

the through holes on the lower sides of three side shell pieces in the right forceps holder are aligned and then locked through the pins and the clamp springs, and the space between every two side shell pieces is kept, namely the pins form a cross shaft which is divided into two sections by the three side shell pieces at the lower part of the right forceps holder, the upper part of the right forceps holder is made into a hook corresponding to the cross shaft, when the forceps holder is in a working state, the hook is hooked on the cross shaft, the connection between the right forceps holder and the right forceps holder is completed, the formation of a pipe fitting accommodating area is completed, when the forceps holder is not in the working state, the hook is separated from the cross shaft, and the right forceps holder is separated from the right forceps holder; the upper part of the left forceps handle is provided with a through hole, and after the through hole is aligned with the through holes on the lower sides of the three shell pieces in the left forceps holder 1, the left forceps handle is locked with the clamp spring through a pin to complete the connection of the left forceps handle and the left forceps holder;

the middle part of the right end face of the left forceps handle and the middle part of the left end face of the right forceps handle are respectively provided with a spring groove extending along the Z-axis direction, the V-shaped spring is arranged in a space formed by the two spring grooves, and two spring feet which are forked towards the left and right directions are inserted between the right end face of the left forceps handle and the left end face of the right forceps handle below the spring grooves; a clamping groove extending along the Z-axis direction is formed in the right end face of the left forceps handle above the spring groove, a protrusion corresponding to the clamping groove is arranged on the left end face of the right forceps handle, and the protrusion is embedded into the clamping groove in a working state; the connecting piece is T-shaped, the left forceps handle and the right forceps handle are arranged between the two connecting pieces, and two sides of the upper parts of the two connecting pieces are respectively hinged with the left forceps handle and the right forceps handle; after the two connecting pieces are hinged with the left and right clamp handles, the positions of the clamping grooves and the protrusions are used as swing centers, the left and right clamp handles form a scissor head, namely the left and right clamp handles can be opened and closed like scissors, and the swing amplitude and the reset are controlled by a V-shaped spring;

recording the distance from the center of the spring groove to the upper end face of the left forceps handle as A1, taking the distance A2 downwards from the spring groove on the right end face of the left forceps handle to obtain a point a1, taking the distance A2 downwards from the spring groove on the left end face of the right forceps handle to obtain a point a2, and gradually inclining the right end face of the left forceps handle and the left end face of the right forceps handle to two sides from the points a1 and a2 respectively, namely forming a bottom consisting of two arcs between the right end face of the left forceps handle and the left end face of the right forceps handle; a2 ═ 0.7-1.2a 1;

and when the pipe fitting is in a working state, an extrusion head in the power device is driven by power to apply upward acting force to the bottom formed by the left forceps handle and the right forceps handle from bottom to top so as to extrude the pipe fitting.

Preferably, the number of the convex ribs is 2-4, and the width and the depth of each convex rib are 1mm-4 mm.

Preferably, the upper grinding head and the side grinding head are replaceable serial products.

Preferably, the upper jaw housing further comprises two outer clamping pieces, the cross sections of the outer clamping pieces are partial circular rings, and the two outer clamping pieces are fixedly connected to the outer sides of the two upper housing pieces through bolts respectively to reinforce the upper jaw.

Preferably, the material of the grinding head is heat-treated die steel.

Compared with the prior art, the invention has the beneficial effects that:

1. adopt scissors head and chain ring to press subassembly hydraulic tong jaw portion, overcome original hydraulic tong, need trade different hydraulic tong when pressing different pipe fittings, it only need trade the chain ring and press the subassembly can, greatly reduced the cost, also increased the convenience of tearing open and trade.

2. The inner wall of the grinding head at the contact position with the pipe fitting is provided with the convex ribs, the grinding head is developed by N times of experiments aiming at the steel-plastic composite sounding pipe, a good water stopping effect is achieved, the inner pipe and the outer pipe and the middle plastic can generate the same and large deformation, the drawing force is greatly increased, and the drawing force far exceeds 3000N required by design.

3. Adopt scissors head and chain ring to press subassembly hydraulic pressure pincers to target in place the back, can kick-back automatically, reduced the artificial influence of not target in place of pressing, improved the crimping quality that the pipe fitting connects greatly.

4. The three-flap chain type ring pressing assembly is adopted, so that the problems that the appearance is influenced, the hidden danger of water leakage is increased and the extrusion quality is difficult to guarantee at the joint of the upper extrusion grinding head and the lower extrusion grinding head due to raised ribs at the joint of the upper extrusion grinding head and the lower extrusion grinding head are well solved.

Drawings

FIG. 1 is a schematic diagram of the structure of an embodiment of the present invention;

FIG. 2 is a schematic diagram showing the distribution of ribs of the grinding head according to the embodiment of the invention;

fig. 3, left side view of fig. 2;

FIG. 4 is an exploded view of an embodiment of the present invention;

FIG. 5 is a schematic structural view of an upper jaw housing in accordance with an embodiment of the present invention;

FIG. 6 is a side jaw housing configuration view of an embodiment of the present invention;

FIG. 7 is a schematic view of a side jaw housing and an upper jaw housing in accordance with an embodiment of the present invention;

FIG. 8 is a schematic structural view of the left and right pressing pliers handles according to the embodiment of the present invention;

FIG. 9 is a schematic view of the state of the embodiment of the present invention when not in operation;

fig. 10 is a schematic diagram of an operating state in the embodiment of the present invention.

Wherein, 1-left jaw, 2-right jaw, 3-upper jaw, 4-left jaw, 5-right jaw, 6-connecting piece, 7-upper grinding head, 8-side grinding head, 9-through hole, 10-convex rib, 11-pipe fitting accommodating area, 12-side jaw housing, 13-upper jaw housing, 14-pin, 15-side housing piece, 16-upper housing piece, 17-V spring, 18-power connecting hole, 19-clamping groove, 20-bulge, 21-hook part, 22-outer clamping piece, 23-bolt, 24-clamping spring, 25-extrusion head, 26-pin seat, 27-side grinding head positioning pin, 28-side grinding head positioning spring, 29-side grinding head positioning groove, 30-spring groove, 31-V type spring foot.

Detailed Description

The present invention is illustrated by the following examples.

Fig. 1 is a schematic structural diagram of an embodiment of the present invention, and fig. 4 is an exploded structural diagram of an embodiment of the present invention, and it can be seen from the two diagrams that the present invention provides a squeeze pliers for pipe fitting, which comprises three jaws that are engaged with each other, two handles that correspond to each other, a connecting member 6 for connecting the two handles, a V-shaped spring 17 and a power device. The forceps holder consists of a forceps holder shell and a grinding head arranged in the forceps holder shell, and a convex rib 8 is arranged on the inner wall of the grinding head.

Taking the axis of the pipe fitting as the Z axis and the cross section of the pipe fitting as a reference surface, the three mutually matched jaws are respectively marked as a left jaw 1, a right jaw 2 and an upper jaw 3 according to the positions of the three mutually matched jaws on the reference surface, and the two mutually corresponding jaw handles are respectively marked as a left jaw handle 4 and a right jaw handle 5 according to the positions of the two mutually corresponding jaw handles on the reference surface.

A jaw shell corresponding to the upper jaw 3 is marked as an upper jaw shell 13, jaw shells corresponding to the left jaw 1 and the right jaw 2 are marked as side jaw shells 12, the two sections of side jaw shells 12 have the same structure and correspond to each other left and right, the shapes of the upper jaw shell 13 and the side jaw shells 12 on a reference plane are both partial circular rings, the upper grinding head 7 is arranged on the inner side of the upper jaw shell 13, and the two side grinding heads 8 are respectively arranged on the inner sides of the left side jaw handle shell 12 and the right side handle shell 12; the state of the squeezing pliers when squeezing the pipe fitting is called as the working state, when the pipe fitting is in the working state, the left side clamp shell 12, the right side clamp shell 12 and the upper clamp shell 13 form a circular ring on the reference surface, the inner walls of the three grinding heads in the three clamp shells form a circular pipe fitting accommodating area 11 on the reference surface, wherein the arc lengths of the inner walls of the two side grinding heads 8 in the pipe fitting accommodating area 11 are the same, and the left side and the right side of the inner walls completely correspond to each other.

The number of the convex ribs 10 is 2-4, and the width and the height of each convex rib 10 are 1mm-4 mm. Fig. 2 is a schematic structural view of a grinding head in an embodiment of the present invention, fig. 3 is a left side view of fig. 2, and as can be seen from fig. 2 and 3, in this embodiment, the number of the ribs 10 is 3. Specifically, the width C and the height H of each rib 10 are both 2 mm. In addition, L in FIG. 2 is the width of the grinding head, and L < 40mm in the present embodiment.

Fig. 5 is a schematic structural view of an upper jaw housing according to an embodiment of the present invention, fig. 6 is a structural view of a side jaw housing according to an embodiment of the present invention, fig. 7 is a schematic structural view of a connection between the side jaw housing and the upper jaw housing according to an embodiment of the present invention, and fig. 8 is a schematic structural view of a left and right pressing jaw handle according to an embodiment of the present invention. As can be seen from fig. 5 to 8, the upper jaw housing 13 is composed of 2 upper housing pieces 16 with the same shape, the side jaw housing 12 is composed of 3 side housing pieces 15 with the same shape, the connecting side of the side housing pieces 15 with the upper housing pieces 16 is referred to as the upper side, and the other side is referred to as the lower side; the cross section of each shell piece on the reference surface is a partial circular ring, and through holes 9 are formed in the two sides of each shell piece; after aligning 2 upper shell pieces 16 along the Z-axis direction, inserting the upper parts of the left and right sides into two shell piece gaps formed by clamping 3 side shell pieces 15 in the left and right two side jaw shells 12 respectively, aligning the through holes 9 at the insertion positions, then penetrating the through holes 9 with the pins 14, and locking the matching positions of the pins 14 and the side shell pieces 15 with the snap springs 24 to complete the connection of the two side jaw shells 12 and the upper jaw shell 13.

The through holes 9 at the lower sides of three side shell pieces 15 in the right forceps holder 2 are aligned and then locked by the pins 14 and the clamp springs 24, and the space between every two side shell pieces 15 is kept by one upper shell piece 16, namely, the pins 14 form a cross shaft which is divided into two sections by the three side shell pieces 15 at the lower part of the right forceps holder 2, the upper part of the right forceps holder 5 is made into a hook 21 corresponding to the cross shaft, when in a working state, the hook 21 is hooked on the cross shaft, the connection between the right forceps holder 5 and the right forceps holder 2 is completed, the formation of a pipe fitting accommodating area 11 is completed, when in a non-working state, the hook 21 is separated from the cross shaft, and the right forceps holder 5 is separated from the right forceps holder 2; the upper part of the left clamp handle 4 is provided with a through hole 9, after the through hole 9 is aligned with the through holes 9 at the lower sides of the three shell pieces 15 in the left clamp 1, the left clamp handle 4 is locked with the clamp spring 24 through the pin 14, and the connection between the left clamp handle 4 and the left clamp 1 is completed.

The middle part of the right end face of the left forceps handle 4 and the middle part of the left end face of the right forceps handle 5 are respectively provided with a spring groove 30 extending along the Z-axis direction, the V-shaped spring 17 is arranged in a space formed by the two spring grooves 30, and two spring feet 31 which are forked towards the left and right directions are inserted between the right end face of the left forceps handle 4 and the left end face of the right forceps handle 5 below the spring grooves 30. Above the spring groove 30, a clamping groove 19 extending along the Z-axis direction is formed on the right end face of the left forceps handle 4, a protrusion 20 corresponding to the clamping groove 19 is arranged on the left end face of the right forceps handle 5, and the protrusion 20 is embedded into the clamping groove 19 in a working state. The connecting piece 6 is T-shaped, the left forceps handle 4 and the right forceps handle 5 are arranged between the two connecting pieces 6, and two sides of the upper parts of the two connecting pieces 6 are respectively hinged with the left forceps handle 4 and the right forceps handle 5. After the two connecting pieces 6 and the left and right forceps handles are hinged, the positions of the clamping grooves 19 and the protrusions 20 are used as swing centers, the left and right forceps handles form a scissor head, namely the left and right forceps handles can be opened and closed like scissors, and the swing amplitude and the reset are controlled by the V-shaped spring 17.

The distance from the center of the spring groove 30 to the upper end face of the left forceps handle 4 is recorded as A1, the distance A2 is taken down from the spring groove 30 on the right end face of the left forceps handle 4 to obtain a point a1, the distance A2 is taken down from the spring groove 30 on the left end face of the right forceps handle 5 to obtain a point a2, and then from the points a1 and a2, the right end face of the left forceps handle 4 and the left end face of the right forceps handle 5 are respectively inclined gradually towards two sides, namely, a bottom formed by two arcs is formed between the right end face of the left forceps handle 4 and the left end face of the right forceps handle 5. A2 ═ 0.7-1.2a 1.

Fig. 9 shows the non-working state of the embodiment of the invention, and as can be seen from fig. 9, when the right forceps handle 5 is separated from the right forceps jaw 2 and the right forceps jaw 2 is pulled upwards on the reference surface, the pipe fitting can be conveniently taken out of or inserted into the squeezing forceps because the right forceps jaw 2, the left forceps jaw 1 and the upper forceps jaw 3 can swing around the pins at the joints among the right forceps jaw 2, the left forceps jaw 1 and the upper forceps jaw 3.

Fig. 10 shows the working state of the embodiment of the present invention. As can be seen from fig. 9-10, spring foot 31 is inserted between the two handles to control the swing amplitude of the scissor head, and the other function is resetting. The two forceps handles are arc-shaped bodies starting from a1 and a2, namely, a bottom part consisting of the two arc-shaped bodies is formed between the two forceps handles. The lower part of the connecting piece 6 is provided with a power connecting hole 18, the power connecting hole 18 is connected with a power device, and when the pipe fitting is in a working state, an extrusion head 25 in the power device is driven by power to apply upward acting force to the bottom formed by the left forceps handle 4 and the right forceps handle 5 from bottom to top so as to extrude the pipe fitting.

Specifically, in the present embodiment, the top of the squeezing head 25 is provided with two rollers which rotate left and right, respectively, and the two rollers squeeze the inner side of the scissor head.

In this embodiment, the upper grinding head 7 and the side grinding head 8 are replaceable serial products.

In this embodiment, the upper jaw housing 13 further includes two outer clamping pieces 22, a cross section of each outer clamping piece 22 is a partial circular ring, and the two outer clamping pieces 22 are respectively fixed to outer sides of the two upper housing pieces 16 by bolts, so as to reinforce the upper jaw 4.

In this embodiment, the material of the grinding head is heat-treated die steel.

In this embodiment, the outer wall of the upper grinding head 7 has a reinforcing rib, the reinforcing rib has a through hole 9, the corresponding surfaces of the two housing pieces 16 have pin bosses 26 corresponding to the through hole 9, a positioning pin 27 passes through the through hole 9, and the two ends of the positioning pin are respectively inserted into the two pin bosses 26, so as to connect the upper grinding head 7 and the two upper housing pieces 16.

The outer wall of the side grinding head 8 is provided with a reinforcing rib, a side grinding head positioning groove 29 parallel to the side shell piece 15 is formed in the reinforcing rib, a side grinding head positioning spring 28 is arranged in the positioning groove, and the upper part of the side grinding head positioning spring 28 is provided with a through hole 9; the middle one 15 of the three side shell pieces 15 constituting the side caliper housing 12 is referred to as a middle shell piece, a pin seat 26 is arranged on the middle shell piece at a position corresponding to the through hole 9, and a side grinding head positioning pin 27 penetrates through the through hole 9 and is inserted into the pin seat 26, so that the connection between the side grinding head 8 and the side shell piece 15 is realized.

In this embodiment, the ends of the side shell pieces 15 and the upper shell piece 16 are rounded to facilitate the swinging of the respective jaws about the pin 14. In addition, each jaw and the scissor head formed by the left and right handles are independent, so that the assembly on site is convenient. Specifically, one end of the two side jaw handle shells 12 connected with the upper jaw handle shell 13 is fixed, namely fixed through a pin clamp spring, and the other end of the two side jaw handle shells is temporarily pinned through a pin and then assembled on a construction site.