CN219685153U - Portable hydraulic expansion pliers - Google Patents

Abstract

The utility model discloses a portable hydraulic expansion clamp which comprises a hydraulic driving piece, an oil cylinder, an elastic reset assembly, a piston, a pressing block, expansion clamp arms symmetrically arranged, a shell, a coupling and a pair of rotating connecting pieces. The elastic reset component is connected with the piston, the hydraulic driving piece is connected with the piston in a transmission way, and at least part of the pressing block is fixedly connected with the piston; the shell is sleeved on the oil cylinder; the rest part of the pressing block is abutted against the first joint part of the expanding clamp arm; two ends of the coupling are respectively and rotatably connected with a first joint part; one end of each rotary connecting piece is rotationally connected with the shell, and the other end is rotationally connected with a second joint part. Due to the limiting effect of the two first joint parts, the pressing block can be prevented from sliding out from between the two first joint parts to cause incapability of resetting, the use safety is ensured, and the tail of the pliers can have a larger expansion angle, so that the application range of the expansion pliers is improved; the expansion pliers can be closed through the elastic reset component, so that the expansion pliers have the advantages of simple structure, small size and portability.

Description

Portable hydraulic expansion pliers

Technical Field

The utility model belongs to the technical field of rescue equipment, and particularly relates to a portable hydraulic expansion clamp.

Background

The portable hydraulic expansion pliers are particularly suitable for places where large rescue equipment is not easy to enter, such as earthquake relief, traffic accident rescue, accident rescue and the like.

In the prior art, the Chinese patent application number 201320670903.1 provides a miniature portable hydraulic expander, which indirectly opens the jaw of the expanding clamp body by pushing a piston, and under the action of the reset action of a tension spring in an oil cylinder, an expanding block can retract, and then an expanding arm of the expanding clamp is closed and reset, so that the whole expander is small and light, and has a simple structure and convenient use. However, when the expander is used, the pressing block may slip from a gap between the two expansion arms, so that the pressing block is blocked and cannot be reset, and the normal use of the equipment cannot be continued; however, when the extension distance of the pressing block is reduced, the expansion angle between the two expansion arms is smaller, so that the application range of the expander is greatly limited.

Based on the foregoing, there is a need for a portable hydraulic expansion clamp to solve the technical problems in the prior art.

Disclosure of Invention

The utility model aims to provide a portable hydraulic expansion clamp, which has the advantages of simple structure, small size and portability, can also improve the application range of the expansion clamp and ensures the use safety of the expansion clamp.

To achieve the purpose, the utility model adopts the following technical scheme:

the utility model provides a portable hydraulic expansion pincers, includes hydraulic drive spare, hydro-cylinder, elasticity reset assembly, piston, top briquetting and symmetrical expansion pincers arm that sets up, elasticity reset assembly with the piston install in the hydro-cylinder, just elasticity reset assembly connect in the piston, hydraulic drive spare transmission connect in the piston, at least part of top briquetting link firmly in the piston, portable hydraulic expansion pincers still includes:

the shell is sleeved on the oil cylinder;

the expansion clamp arm comprises a clamp head and a clamp tail, the clamp head comprises a first joint part and a second joint part, and the rest part of the pressing block is abutted against the first joint part;

the two ends of the coupling are respectively and rotatably connected with one first joint part;

and one end of each rotating connecting piece is rotatably connected with the shell, and the other end of each rotating connecting piece is rotatably connected with one second joint part.

Optionally, the rotating connecting piece comprises a connecting plate, a threaded connecting piece and a rotating shaft, wherein a first through hole and a second through hole for the threaded connecting piece and the rotating shaft to penetrate are respectively arranged at two ends of the connecting plate;

the shell is provided with a threaded connecting hole which is opposite to the first through hole, and the threaded connecting piece is arranged in the first through hole in a penetrating manner after being connected to the threaded connecting hole in a threaded manner;

the second joint part is provided with a shaft hole which is opposite to the second through hole, and the rotating shaft rotatably penetrates through the second through hole and the shaft hole.

Optionally, the oil cylinder, the piston, the expansion clamp arm, the coupling, the connecting plate and the shell are all manufactured by adopting aluminum materials.

Optionally, the surface of the tail contacting the piece to be clamped is provided with inserts.

Optionally, the teeth of the insert are barb-like.

Optionally, a first sealing ring is sleeved on the outer wall surface of the piston.

Optionally, the portable hydraulic expanding forceps further comprises a T-shaped guide sleeve, the T-shaped guide sleeve is inserted in the oil cylinder in a limiting mode, the T-shaped guide sleeve is provided with a guide through hole, and the piston reciprocates through the guide through hole.

Optionally, a first exhaust hole is formed in the guide sleeve, the first exhaust hole is communicated with the oil cylinder, a second exhaust hole corresponding to the first exhaust hole is formed in the shell, and the second exhaust hole is communicated with the outside.

Optionally, the hydraulic drive employs a manual hydraulic pump.

Optionally, the elastic reset component comprises a spring, a first fixing seat and a second fixing seat, wherein two ends of the spring are respectively fixedly connected with the first fixing seat and the second fixing seat, the first fixing seat is fixedly connected with the oil cylinder, and the second fixing seat is fixedly connected with the piston.

Compared with the prior art, the utility model has the beneficial effects that:

in the portable hydraulic expansion pliers provided by the utility model, when the pressing block upwards presses the first joint parts under the pushing action of the piston, the two first joint parts rotate and are relatively close, and the two second joint parts rotate and are relatively far away, so that the two pliers tails are relatively far away, and the expansion process of the expansion pliers is completed. At the moment, due to the limiting effect of the two first joint parts, the pressing block can be prevented from sliding out from between the two first joint parts to cause incapability of resetting, so that the safety of the expansion pliers in the use process is ensured, the pressing block can extend out a larger distance to enable the pliers tail to have a larger expansion angle, and the application range of the expansion pliers is further improved; in addition, when the elastic reset component connected with the piston resets and rebounds, the pressing block can be contracted, and then the tail of the pliers is closed, so that the closing process of the expanding pliers is completed, and the expanding pliers have the advantages of simple structure, small size, portability and easy and convenient use.

Drawings

FIG. 1 is a front view of a portable hydraulic expansion clamp provided in this embodiment with the arms of the expansion clamp in a closed position and with the shields hidden;

FIG. 2 is a front view showing the internal structure of the portable hydraulic expanding pliers according to the present embodiment when the expanding pliers arms are closed;

FIG. 3 is a side view of the internal structure of the portable hydraulic expansion pliers according to the present embodiment with the expansion pliers arms in the closed position;

fig. 4 is a schematic perspective view of the portable hydraulic expanding forceps according to the embodiment, when the expanding forceps arms are in an expanded state;

fig. 5 is a front view of the internal structure of the portable hydraulic expansion pliers according to the present embodiment, when the expansion pliers arms are in the expanded state.

In the figure:

10. an oil cylinder;

20. an elastic reset assembly; 201. a spring; 202. a first fixing seat; 2021. a first groove portion; 2022. a first end cap portion; 2023. a threaded portion; 203. the second fixing seat; 2031. a second groove portion; 2032. a second end cap portion;

30. a piston; 301. a first annular groove;

40. pressing a block; 401. a second annular groove; 402. a third annular groove;

50. expanding the clamp arm; 501. a clamp head; 5011. a first joint part; 5012. a second joint part; 502. a tail of the pliers;

60. a housing; 601. a second exhaust hole;

70. a coupling;

80. rotating the connecting piece; 801. a connecting plate; 8011. a first through hole; 8012. a second through hole; 802. a threaded connection; 803. a rotating shaft;

90. a quick connector;

100. a dust cap;

110. a threaded fastener;

120. a first seal ring;

130. a second seal ring;

140. a retainer ring;

150. a T-shaped guide sleeve; 1501. a first exhaust hole;

160. a shield;

170. and (5) inlaying teeth.

Detailed Description

In the description of the present utility model, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Wherein the terms "first position" and "second position" are two different positions.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixed or removable, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The following description of the embodiments of the present utility model will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the utility model are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present utility model without making any inventive effort, are intended to be within the scope of the present utility model.

The portable hydraulic expansion pliers provided by the present utility model will be described with reference to fig. 1 to 5 and the specific embodiment.

As shown in fig. 1 to 2, the portable hydraulic expansion pliers according to the present embodiment include a hydraulic driving member (not shown), an oil cylinder 10, an elastic restoring assembly 20, a piston 30, a pressing block 40, a pair of symmetrically disposed expansion pliers arms 50, a housing 60, a coupling 70, and a pair of rotational connectors 80. The elastic reset assembly 20 and the piston 30 are installed in the oil cylinder 10, the elastic reset assembly 20 is connected with the piston 30, the hydraulic driving piece is in transmission connection with the piston 30, and at least part of the pressing block 40 is fixedly connected with the piston 30. The following describes the structure and the respective working principle in detail with reference to the accompanying drawings.

Optionally, the hydraulic driving part selects a hydraulic pump, the quick connector 90 is installed at the oil inlet of the oil cylinder 10, and the high-pressure liquid oil provided by the hydraulic driving part can enter the oil cylinder 10 by opening the quick connector 90, so that the piston 30 in the oil cylinder 10 generates linear motion, the quick connector 90 can conveniently realize connection and separation between the oil cylinder 10 and the hydraulic driving part, and the working efficiency is improved. Preferably, the hydraulic pump is a manual hydraulic pump, is simple and convenient to operate, has high reliability, and is light and portable. Optionally, in this embodiment, the dustproof cap 100 is sealed at the interface of the quick connector 90, so as to prevent dust, moisture and other impurities from accumulating on the interface of the quick connector 90 in a non-working state, and ensure the cleaning and use safety of the quick connector 90.

Referring to fig. 1, the oil cylinder 10 has a structure with a thick upper end and a thin lower end (the direction indicated by an arrow in the figure is upward), namely, the inner diameter of a space for placing the piston 30 in the oil cylinder 10 is increased in the oil cylinder 10, so that the stress area of the piston 30 is increased under the same hydraulic pressure, the bearing capacity is improved, and the pushing force of the piston 30 can reach 16 tons; meanwhile, the lower end of the oil cylinder 10 is thinned, and on the basis of ensuring that the elastic reset assembly 20 can be placed in a limiting mode, the weight of the whole oil cylinder 10 is reduced, and the oil cylinder is convenient for operators to hold. Further, in this embodiment, a plurality of flanges are further provided at the lower end of the cylinder 10, so that the holding area can be increased, the hand sliding is prevented, and the safety and stability of holding are improved.

The elastic reset component 20 has an elastic reset function, when the hydraulic oil pushes the piston 30 to move upwards, the piston 30 can push the pushing block 40 to push the expansion clamp arms 50, so that the two expansion clamp arms 50 are relatively far away, and the expansion movement of the expansion clamp is completed; at this time, the elastic reset assembly 20 deforms under the action of the pulling force of the piston 30, the self-reset movement tendency is provided, when the hydraulic pump is depressurized, the piston 30 gradually reduces the pulling force on the elastic reset assembly 20, so that the elastic reset assembly 20 can reset, and in the process, the piston 30 is pulled to move downwards, so that the hydraulic oil in the oil cylinder 10 returns to the oil tank of the hydraulic pump according to the original path, at this time, the piston 30 is retracted into the oil cylinder 10, the pushing action on the expansion clamp arms 50 is eliminated at this time by the pushing block 40, and the two expansion clamp arms 50 can be relatively close, so that the closing of the expansion clamp is completed. The expansion and closing of the expansion pliers are completed by arranging the elastic resetting assembly 20, so that the expansion pliers are simple in structure, small, exquisite and portable, and easy and convenient to use.

Specifically, referring to fig. 2, the elastic restoring assembly 20 includes a spring 201, a first fixing seat 202 and a second fixing seat 203, two ends of the spring 201 are respectively and fixedly connected to the first fixing seat 202 and the second fixing seat 203, the first fixing seat 202 is fixedly connected to the cylinder 10, and the second fixing seat 203 is fixedly connected to the piston 30.

Illustratively, in this embodiment, the elastic restoring assembly 20 is fixed in the expanding pliers in the following manner: firstly, the caliber of an oil inlet of the oil cylinder 10 is designed to be smaller than the inner diameter of the lower end of the oil cylinder 10; secondly, the first fixing base 202 is of a cross-shaped structure and comprises a first groove part 2021, a first end cover part 2022 and a threaded part 2023 which are sequentially connected, the diameter of the first groove part 2021 is not larger than the inner diameter of the spring 201, the diameter of the first end cover part 2022 is not larger than the inner diameter of the lower end of the oil cylinder 10, the diameter of the threaded part 2023 is not larger than the caliber of an oil inlet of the oil cylinder 10, one end of the spring 201 is sleeved and can be in limiting clamping connection with the first groove part 2021, the quick connector 90 is provided with an inserting hole with internal threads, the threaded part 2023 penetrates through the oil inlet and is in threaded connection with a quick connector, and the first end cover part 2022 is abutted against a step surface at the oil inlet so that the first fixing base 202 is fixedly connected with the piston 30 and the quick connector; again, the second fixing seat 203 is a T-shaped structure, which includes a second groove portion 2031 and a second end cap portion 2032 with diameters decreasing in sequence, the diameter of the second groove portion 2031 is not larger than the inner diameter of the spring 201, the other end of the spring 201 is sleeved and can be in limit clamping connection with the second groove portion 2031, the second end cap portion 2032 is abutted against the piston 30, the second fixing seat 203 has a threaded hole penetrating through the second groove portion 2031 and the second end cap portion 2032 at the same time, the piston 30 has a through hole, a part of the structure of the pressing block 40 can be in limit insertion connection in the through hole, the through hole is arranged corresponding to the threaded hole, and after the threaded end of the threaded fastener 110 (such as a bolt, a screw, etc.) penetrates through the through hole, the threaded connection is in the threaded hole, so that the second fixing seat 203 and the piston 30 are fixedly connected. Thus, the fixed connection process of the elastic reset assembly 20, the piston 30 and the oil cylinder 10 is completed, the connection compactness is high, the reliability is high, and the detachable replacement is realized, so that the expanding clamp is convenient to maintain and maintain.

Optionally, referring to fig. 3, in this embodiment, a first sealing ring 120 is sleeved on an outer wall surface of the piston 30, and the first sealing ring 120 can effectively fill a gap between the piston 30 and the cylinder 10, prevent hydraulic oil from leaking from the gap, and ensure stability and safety during a linear movement process of the piston 30. The first sealing ring 120 is preferably a gray ring, which has good sealing performance and strong wear resistance, so as to meet the requirement of the high-pressure hydraulic system. Optionally, the piston 30 is provided with a first annular groove 301, and the first sealing ring 120 is embedded in the first annular groove 301, so as to reduce abrasion of the first sealing ring 120 during sliding of the piston 30 and the oil cylinder 10.

Optionally, in this embodiment, in order to ensure tightness between the top pressing block 40 and the piston 30, a second sealing ring 130 and a retainer ring 140 are sleeved on an outer wall surface of the top pressing block 40, and a second annular groove 401 and a third annular groove 402 are formed on the top pressing block 40, and the second sealing ring 130 and the retainer ring 140 are respectively embedded in the second annular groove 401 and the third annular groove 402, so that a gap between the top pressing block 40 and the piston 30 for leakage of hydraulic oil can be prevented by the second sealing ring 130 and the retainer ring 140, and safety stability of the sealing performance is ensured.

Optionally, in order to ensure the accuracy of the linear movement of the piston 30 in the cylinder 10, in this embodiment, the expanding pliers further includes a T-shaped guide sleeve 150, where the smaller diameter end of the T-shaped guide sleeve 150 is inserted into the cylinder 10 in a limited manner, and the T-shaped guide sleeve 150 has a guide through hole, where the piston 30 can reciprocate in a linear movement manner through the guide through hole, and the guide through hole can accurately position the linearly moving piston 30, so that the movement range of the piston 30 can be effectively limited, and the accuracy of the movement of the piston 30 is ensured.

Further, the T-shaped guide sleeve 150 is provided with a first vent hole 1501, and the first vent hole 1501 is communicated with the oil cylinder 10; the housing 60 is provided with a second vent hole 601 corresponding to the first vent hole 1501, and the second vent hole 601 is communicated with the outside. When the piston 30 moves in the oil cylinder 10, the gas in the non-hydraulic oil cavity between the piston 30 and the oil cylinder 10 can be discharged outwards along the first exhaust hole 1501 and the second exhaust hole 601, so that the pressure in the oil cylinder 10 can be reduced, the phenomenon that the gas in the non-hydraulic oil cavity is swelled in the moving process of the piston 30, the movement of the piston 30 becomes difficult, and the safety and the practicability of the piston 30 and the oil cylinder 10 are improved. In this embodiment, a first vent 1501 is formed on two opposite sides of the T-shaped guide sleeve 150, and a second vent 601 is formed on two opposite sides of the housing 60, so as to further improve the venting efficiency between the piston 30 and the cylinder 10.

Referring to fig. 2, the casing 60 provided in this embodiment is sleeved on the oil cylinder 10, and threads can be formed on the inner side wall of the casing 60 and the outer side wall of the oil cylinder 10, so that the casing 60 can be connected to the oil cylinder 10 through threads, so as to improve the connection stability between the two; the expanding clamp arm 50 comprises a clamp head 501 and a clamp tail 502, the clamp head 501 comprises a first joint part 5011 and a second joint part 5012, the rest part of the pressing block 40 (namely the part of the pressing block 40 exposed out of the piston 30) is abutted against the first joint part 5011, and two ends of the coupling 70 are respectively connected with one first joint part 5011 in a rotating way; one end of each of the rotational links 80 is rotatably coupled to the housing 60 and the other end is rotatably coupled to a second knuckle 5012.

Through the above arrangement, when the pressing block 40 presses the first joint parts 5011 upward under the pushing action of the piston 30, the two first joint parts 5011 rotate and relatively approach, and the two second joint parts 5012 rotate and relatively depart, so that the two tail 502 are relatively separated, and the expanding process of the expanding pliers is completed. At this time, due to the limiting effect of the two first joint parts 5011, the pressing block 40 can be prevented from sliding out from between the two first joint parts 5011 to cause incapability of resetting, so that the safety of the expansion pliers in the use process is ensured, the pressing block 40 can extend out a larger distance to enable the pliers tail 502 to have a larger expansion angle, and the application range of the expansion pliers is further improved.

Specifically, as shown in fig. 1 and 2, the rotary connecting member 80 includes a connecting plate 801, a threaded connecting member 802, and a rotating shaft 803, and a first through hole 8011 and a second through hole 8012 through which the threaded connecting member 802 and the rotating shaft 803 pass are respectively provided at two ends of the connecting plate 801; the casing 60 is provided with a threaded connection hole opposite to the first through hole 8011, and the threaded connection piece 802 is threaded on the threaded connection hole and then penetrates through the first through hole 8011, so that the connection plate 801 can rotate relative to the casing 60; the second joint 5012 is provided with a shaft hole which is arranged along with the second through hole 8012, and the rotating shaft 803 rotatably penetrates through the second through hole 8012 and the shaft hole, so that the expanding clamp arm 50 can be rotatably connected to the connecting plate 801 through the second joint 5012. In this way, the relative rotation process of the expanding clamp arm 50 can be realized by arranging the connecting plate 801, the threaded connecting piece 802 and the rotating shaft 803, which are simple in structure, thereby being beneficial to improving the structural stability of the whole expanding clamp and reducing the production cost.

Optionally, the expanding pliers further include a protecting cover 160, where the protecting cover 160 is made of a rubber material with elasticity, so that the protecting cover 160 can be wrapped around the casing 60, the connecting plate 801, the first joint 5011 and the second joint 5012, so as to avoid the inner structure of the expanding pliers from being damaged by the external environment.

In this embodiment, the oil cylinder 10, the piston 30, the expansion clamp arm 50, the coupling 70, the connecting plate 801 and the housing 60 are all manufactured from an aluminum material with high strength and super hardness, and compared with the conventional manufacturing method using steel materials, the structural weight of the whole expansion clamp can be greatly reduced, so that the length between the clamp tail 502 and the clamp head 501 of the expansion clamp arm 50 can be properly lengthened, the distance h between the two expansion clamp arms 50 can reach 200mm after the expansion clamp arms 50 are expanded, and the weight ratio of the whole expansion clamp arm 50 is reduced by 2/3 compared with the manufacturing method using steel materials. Of course, the length and the expansion distance of the expansion clamp arm 50 are not limited specifically, and those skilled in the art can freely design the length of the expansion clamp arm 50 according to the actual production requirement, so as to form different expansion distances, thereby meeting the requirement of the actual working condition.

Referring to fig. 1, fig. 4 and fig. 5, after the expanding clamp arm 50 is manufactured by using aluminum, in this embodiment, the surface of the clamp tail 502 contacting the workpiece to be clamped is provided with the insert 170, and the insert 170 may be manufactured by using alloy steel after being treated by a quenching process; in some other embodiments, carbon steel or high speed steel may be used to provide a significant increase in stiffness at the point where the expanding jaw arms 50 contact the piece to be clamped, avoiding damage to the expanding jaw arms 50 by the piece to be clamped. More specifically, the teeth of the insert 170 are barb-shaped, so that the expansion jawarms 50 can be prevented from slipping with the workpiece to be clamped during the expansion process, and the connection stability between the expansion jawarms 50 and the workpiece to be clamped is improved.

It is to be understood that the above examples of the present utility model are provided for clarity of illustration only and are not limiting of the embodiments of the present utility model. Other variations or modifications of the above teachings will be apparent to those of ordinary skill in the art. It is not necessary here nor is it exhaustive of all embodiments. Any modification, equivalent replacement, improvement, etc. which come within the spirit and principles of the utility model are desired to be protected by the following claims.

Claims (10)

1. The utility model provides a portable hydraulic expansion pincers, includes hydraulic drive spare, hydro-cylinder (10), elasticity reset subassembly (20), piston (30), roof briquetting (40) and symmetrical expansion pincers arm (50) that set up, elasticity reset subassembly (20) with piston (30) install in hydro-cylinder (10), just elasticity reset subassembly (20) connect in piston (30), hydraulic drive spare transmission connect in piston (30), at least part of roof briquetting (40) link firmly in piston (30), its characterized in that, portable hydraulic expansion pincers still include:

the shell (60) is sleeved on the oil cylinder (10);

the expanding clamp arm (50) comprises a clamp head (501) and a clamp tail (502), the clamp head (501) comprises a first joint part (5011) and a second joint part (5012), and the rest part of the pressing block (40) is abutted against the first joint part (5011);

the two ends of the shaft coupling (70) are respectively connected with one first joint part (5011) in a rotating way;

a pair of rotational connectors (80), one end of each rotational connector (80) is rotatably connected to the housing (60), and the other end is rotatably connected to one of the second joint parts (5012).

2. The portable hydraulic expansion wrench according to claim 1, wherein the rotary connecting piece (80) comprises a connecting plate (801), a threaded connecting piece (802) and a rotating shaft (803), and a first through hole (8011) and a second through hole (8012) for the threaded connecting piece (802) and the rotating shaft (803) to penetrate are respectively formed at two ends of the connecting plate (801);

the shell (60) is provided with a threaded connection hole which is opposite to the first through hole (8011), and the threaded connection piece (802) is threaded to the threaded connection hole and then penetrates through the first through hole (8011);

the second joint part (5012) is provided with a shaft hole which is opposite to the second through hole (8012), and the rotating shaft (803) rotatably penetrates through the second through hole (8012) and the shaft hole.

3. The portable hydraulic expansion tong according to claim 2, characterized in that the oil cylinder (10), the piston (30), the expansion tong arms (50), the coupling (70), the connection plate (801) and the housing (60) are manufactured from aluminium material.

4. A portable hydraulic expansion wrench as claimed in claim 3, wherein the surface of the wrench tail (502) contacting the member to be gripped is provided with a cutting insert (170).

5. The portable hydraulic expansion wrench of claim 4, wherein teeth of the insert (170) are barb-like.

6. Portable hydraulic expansion clamp according to claim 1, characterized in that the outer wall surface of the piston (30) is sleeved with a first sealing ring (120).

7. The portable hydraulic expansion tong according to claim 1, further comprising a T-shaped guide sleeve (150), wherein the T-shaped guide sleeve (150) is inserted into the oil cylinder (10) in a limited manner, and the T-shaped guide sleeve (150) has a guide through hole, through which the piston (30) reciprocates.

8. The portable hydraulic expansion wrench as claimed in claim 7, wherein the T-shaped guide sleeve (150) is provided with a first vent hole (1501), the first vent hole (1501) is communicated with the cylinder (10), the housing (60) is provided with a second vent hole (601) corresponding to the first vent hole (1501), and the second vent hole (601) is communicated with the outside.

9. The portable hydraulic expansion clamp of claim 1, wherein the hydraulic drive employs a manual hydraulic pump.

10. The portable hydraulic expansion clamp according to claim 1, wherein the elastic reset assembly (20) comprises a spring (201), a first fixing seat (202) and a second fixing seat (203), two ends of the spring (201) are respectively fixedly connected with the first fixing seat (202) and the second fixing seat (203), the first fixing seat (202) is fixedly connected with the oil cylinder (10), and the second fixing seat (203) is fixedly connected with the piston (30).