CN111173785A

CN111173785A - Hydraulic hammer stress application device and control method

Info

Publication number: CN111173785A
Application number: CN202010161102.7A
Authority: CN
Inventors: 曹斌; 刘源; 刘岩; 刘涛
Original assignee: Taian Hengda Machinery Co ltd; Taian Hangshen Machinery Co ltd
Current assignee: Taian Hengda Machinery Co ltd; Taian Hangshen Machinery Co ltd
Priority date: 2020-03-10
Filing date: 2020-03-10
Publication date: 2020-05-19

Abstract

The invention discloses a hydraulic hammer force-applying device which comprises a drop hammer system, wherein the drop hammer system comprises a hydraulic station, a lifting cylinder, a reversing valve and a force-applying energy accumulator, the lifting cylinder is a double-acting single-piston-rod hydraulic cylinder which is vertically arranged and provided with a downward piston rod, the end part of the piston rod of the lifting cylinder is connected with a heavy hammer, and the force-applying energy accumulator or an external force-applying energy accumulator is arranged in a rodless cavity. And the heavy hammer after the reversing valve is reset and communicated with the lifting cylinder and the oil return pipe falls down at an accelerated speed under the resultant force action of gravity and the falling hammer stress application energy accumulator. The hydraulic hammer has the double effects of improving the descending force of the hydraulic hammer drop and reducing the liquid flow resistance, and correspondingly has the functions and characteristics of improving the drop hammer speed, the impact energy and the impact force and saving energy.

Description

Hydraulic hammer stress application device and control method

Technical Field

The invention relates to the technical field of engineering machinery, in particular to a hydraulic hammer force application device for underwater, overwater and land piling, ramming, crushing and other striking operations and an operation method.

Background

At present, a heavy hammer lifting cylinder of a hydraulic hammer is generally provided with a double-acting double-piston rod type or a double-acting single-piston rod type common oil cylinder, and is externally connected with a low-pressure energy accumulator or a low-pressure energy accumulator and a high-pressure energy accumulator, and control systems are different.

When the heavy hammer is lifted, oil is discharged from the upper cavity of the lifting cylinder, and when the heavy hammer falls, oil is supplemented to the upper cavity, which is approximately equal to a register, so that the hydraulic oil has large idle flow loss and low energy efficiency. Even if a force application measure is adopted, the main effect is to partially offset or offset the liquid flow resistance in the high-speed hammer drop process, and the force application effect is limited.

As a typical case of the hydraulic hammer, for example, a TZ-1900 double-acting type full hydraulic pile hammer of Taiyuan heavy machinery group Limited company, the mass of the hammer is 200t, the maximum drop height is 1.5m, the impact energy at the maximum drop height is 1900kJ, the impact energy is only 63% of the potential energy of the hammer, and the hammer is equivalent to a free falling body less than 1 m. The force application effect of double-acting full hydraulic pressure does not offset the oil discharge and oil supplement resistance in the hammer drop process, the efficiency loss is huge, and the general level of a single-acting hydraulic hammer without force application is not reached. It can be seen from this example that the "double-acting full hydraulic pile hammer" and the related drop hammer force application technology, which directly apply pressure oil to the upper chamber of the lifting cylinder, may not be able to effectively increase the drop hammer speed.

The well matched differential drop hammer stress application technology can effectively improve the drop hammer speed, namely, the product of the two side surface differences of the piston of the double-acting single-piston rod type oil cylinder and the balance pressure of the two cavities is utilized to apply stress to push the piston to accelerate to descend. The balance pressure is the instantaneous liquid flow resistance of oil discharge of the rod cavity and oil supplement of the rodless cavity in the hammer falling process is equal, and the liquid flow resistance needs to be reduced as much as possible, so that the differential force mainly counteracts the liquid flow resistance. When the matching is good, the falling hammer kinetic energy is close to, equal to or slightly greater than the potential energy, and compared with the prior case, the technical advantage is obvious.

The ratio of kinetic energy to potential energy of the hydraulic hammer which can be constructed at sea abroad is 1.5-2, and the striking efficiency is 2-3 times of the above case.

The hydraulic hammer for offshore construction can work on water, water and land generally. In order to overcome the buoyancy, the mass of the whole machine is about 2 times of that of the heavy hammer, and a counterweight is additionally arranged during deep sea construction.

The force applied by the drop hammer is not more than the gravity of the support shell and the associated part of the heavy hammer, otherwise, the force applied initially jacks up the support shell and the associated part to generate impact. The weight of the support shell and the related parts of the hydraulic hammer for offshore construction is close to or exceeds that of the heavy hammer, and more effective drop hammer stress application measures are facilitated.

In the prior art, hydraulic oil entering and exiting an upper cavity of a lifting cylinder basically belongs to reactive flow. The upper cavity of the double-acting double-piston rod type is provided with a piston rod which cannot be utilized; the rodless cavity (upper cavity) of the double-acting single-piston rod type lifting cylinder is an available cavity.

In recent years, construction work such as offshore piling has been increasing, and the work has gradually expanded to deeper sea areas. The prior art pummel efficacy is too low. As the submergence depth increases, the striking efficiency further decreases. Even if the technical problems of water pressure influence and the like are solved, the underwater operation is not suitable. The main reason is that the weight of the hydraulic hammer needs to be increased due to the low efficiency of the hydraulic hammer when the striking energy is required for a certain time. As the height of the whole machine cannot be increased without limit, the section size must be increased. As the cross-sectional dimension increases, the volume of air within the housing cavity increases in the order of the square, with a concomitant increase in the pressure surface of the housing. The shell required for overcoming the influence of buoyancy and water pressure has huge mass and no practical value.

There is a need to provide a high-efficiency hydraulic hammer technology, which is suitable for the requirements of water, underwater and land construction.

Disclosure of Invention

The invention aims to provide a hydraulic hammer force application device and an operation method.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a hydraulic hammer force-applying device comprises a drop hammer system, wherein the drop hammer system comprises a lifting cylinder, a reversing valve, a force-applying energy accumulator and a hydraulic station, the lifting cylinder is a double-acting single-piston-rod hydraulic cylinder which is vertically arranged and provided with a downward piston rod, the end part of the piston rod of the lifting cylinder is connected with a heavy hammer, and a force-applying energy accumulator or an external force-applying energy accumulator is arranged in a rodless cavity. The reversing valve is a two-position three-way reversing valve, a pressure port is closed, an oil outlet is communicated with an oil return port, the oil return port after reversing is communicated with the oil outlet, the stress application energy accumulator is an air bag type energy accumulator or a piston type energy accumulator, a pressure pipe of the hydraulic station is connected with the pressure port of the reversing valve, the oil return pipe of the hydraulic station is connected with the oil return port of the reversing valve, and the oil outlet of the reversing valve is connected with an oil port of a rod cavity of the lifting cylinder.

Preferably, the hammer lifting device is provided with an oil inlet energy accumulator, the oil inlet energy accumulator is connected with a pressure pipe of the hydraulic station, energy is stored when a hammer falls, oil is supplied to a rodless cavity of the lifting cylinder together with the hydraulic station when the hammer is lifted, the hammer lifting time is shortened, and the striking frequency is improved.

Preferably, the hydraulic hammer impact hammer is provided with an oil return energy accumulator, the oil return energy accumulator is connected with an oil return pipe of the hydraulic station, and part of hydraulic oil is deposited when the hammer drops at a high speed, so that the oil return resistance is reduced, and the hammer dropping speed and the impact efficiency are correspondingly improved.

Preferably, the reversing valve is replaced by a two-position four-way reversing valve, a three-position four-way reversing valve and a cartridge valve which can realize the same function. For example, a normally open oil outlet closed two-position four-way reversing valve for standard supply, a pressure port closed three-position four-way reversing valve for standard supply with the other oil ports communicated at the middle position, and a cartridge valve group consisting of two-way basic plug-ins and an electromagnetic reversing valve. The small and medium hydraulic hammers can adopt electromagnetic, electro-hydraulic and hydraulic reversing valves, and the large and medium hydraulic hammers have large flow and can select cartridge valve groups.

Preferably, when the hydraulic station is a constant-flow hydraulic system, the pressure port, the oil outlet and the oil return port are normally open when the reversing valve is at a static position. Such as a low-pressure constant-flow hydraulic system in a fixed displacement pump of a loader and the like.

Preferably, the boosting energy accumulator arranged in the rodless cavity of the lifting cylinder comprises a cylinder body, a protecting piece, an air bag, a gland and an inflation valve. The upper end of the cylinder body is provided with a gland mounting surface and a mounting hole, the piston and the piston rod assembly are arranged in the inner cavity of the cylinder body, a protection piece for preventing the piston and the fixing piece thereof from damaging the air bag is arranged on the piston, the inflation valve is arranged above the gland, the air bag is arranged below the gland, and the gland is fixed at the upper end of the cylinder body in a sealing way after the air bag is arranged in the rodless cavity of. The boosting energy accumulator is arranged in the lifting cylinder, so that the structure is compact, the resistance is small, and the reliability is improved. The rodless cavity of the lifting cylinder can be externally connected with a boost accumulator when the height of the whole hydraulic hammer is limited or other requirements require.

Preferably, the boosting energy accumulator arranged in the lifting cylinder is a piston type energy accumulator with an inflation valve arranged on a rodless cavity cylinder body. If the existing lifting cylinder is directly utilized, the piston type energy accumulator formed by additionally arranging an inflation valve at the oil port of the rodless cavity is adopted.

Preferably, the guide sleeve of the lifting cylinder and the corresponding cylinder body are provided with communicated radial oil holes, sealing elements are arranged on two sides of the oil hole with the outer diameter of the guide sleeve, sealing elements are arranged on two sides of the oil hole with the inner diameter of the guide sleeve, and the oil hole is connected with an oil return pipe and used for lubricating and cooling the sealing elements and preventing leakage and pollution.

The hydraulic hammer stress application device and the control method comprise the following steps:

and S1, the hydraulic station is started and is connected with an oil way of the hydraulic hammer, then the oil is filled into the oil inlet accumulator for energy storage, the rod cavity of the lifting cylinder is communicated with an oil return pipe of the hydraulic station through an oil outlet and an oil return port of the reversing valve, and the heavy hammer is positioned at the bottom dead center.

S2, after the reversing valve is reversed, the pressure port is communicated with the oil outlet, the pressure pipe and the oil inlet accumulator supply oil to the rod cavity of the lifting cylinder 1 through the pressure port and the oil outlet of the reversing valve simultaneously to push the piston to move upwards, and the weight is lifted while compressing the boosting accumulator to accumulate energy.

S3, when the set lifting height is reached, the reversing valve resets, the oil outlet is communicated with the oil return port, the pressure port is sealed, the heavy hammer falls down at an accelerated speed under the combined action of gravity and the stress application energy accumulator, oil discharged from the rod cavity of the lifting cylinder is discharged through the oil outlet and the oil return port of the reversing valve, and the oil return energy accumulator is stored when the oil discharge resistance is large. The hydraulic station charges the oil charge accumulator during a hammer drop.

Compared with the prior art, the invention has the advantages that:

the drop hammer stress application energy accumulator is arranged in the lifting cylinder, and oil discharge and oil supplement resistance of a rodless cavity does not exist; the boosting energy accumulator directly pushes the piston to accelerate downwards by utilizing the energy stored when the heavy hammer is lifted, and the boosting effect is obvious and energy is saved.

Therefore, the hydraulic hammer has the double effects of improving the oil discharging and supplementing resistance and the stress application effect when the hydraulic hammer drops, and correspondingly has the effects and characteristics of improving the drop hammer speed, the impact energy and the impact force and the energy-saving effect.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a block diagram of a first embodiment of the present invention.

Fig. 2 is a structural diagram of a second embodiment of the present invention.

Fig. 3 is a structural diagram of a third embodiment of the present invention.

Detailed Description

The preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art, and the scope of the present invention will be more clearly and clearly defined.

Example 1

Fig. 1 is a drawing of an embodiment, which is a basic scheme of the invention and is an underwater construction hydraulic hammer with high technical requirements.

The utility model provides a hydraulic hammer thrust augmentation device, includes the hammer system that falls, and the hammer system that falls includes hydraulic pressure station, promotion jar 1, switching-over valve 2, thrust augmentation accumulator 3, and promotion jar 1 is vertical setting, the downward two-way single piston rod pneumatic cylinder of piston rod, and its piston rod tip hookup has weight 6, and no pole intracavity establishes thrust augmentation accumulator 3, switching-over valve 2 seals for the pressure port, two-position three way switching-over valve of oil-out and oil return opening intercommunication, the hydraulic fluid port communicates after the switching-over with the oil-out, the thrust augmentation accumulator is 3 gasbag formula accumulators or piston accumulator, and the pressure pipe of hydraulic pressure station connects the pressure port of switching-over valve 2, and the oil return pipe of hydraulic pressure station connects the oil return opening of switching-over valve 2, and the oil-out of switching-over valve 2.

When the boosting energy accumulator 3 arranged in the rodless cavity of the lifting cylinder 1 is of a leather bag type, air and nitrogen can be injected into a gap between the rodless cavity and the boosting energy accumulator 3, and hydraulic oil can also be injected into the gap or residual air in the gap can be directly utilized.

When the boosting energy accumulator 3 arranged in the rodless cavity of the lifting cylinder 1 is a piston type, air or nitrogen is injected.

The boost energy accumulator 3 can be independently arranged and is connected with the rodless cavity of the lifting cylinder 1 by a pipe fitting.

In order to fully utilize hydraulic power, shorten the hammer lifting time and improve the striking frequency, the hammer lifting device is further provided with an oil inlet energy accumulator 4, the oil inlet energy accumulator 4 is connected with a pressure pipe of a hydraulic station, energy is accumulated when a hammer falls, and oil is supplied to a rodless cavity of the lifting cylinder 1 together with the hydraulic station when the hammer is lifted. The hydraulic power source is a constant flow type hydraulic system of a medium and low pressure constant delivery pump of a loader and the like, and the oil inlet accumulator 4 is not arranged when other requirements are needed.

In order to reduce the oil discharge resistance of a rod cavity of the lifting cylinder 1 during hammer dropping and correspondingly improve the hammer dropping speed and the striking efficiency, the oil return energy accumulator 5 is arranged, the oil return energy accumulator 5 is connected with an oil return pipe of a hydraulic station, and part of hydraulic oil is deposited during high-speed hammer dropping so as to reduce the oil return resistance and correspondingly improve the hammer dropping speed and the striking efficiency. The high-frequency beating small-stroke small-micro hydraulic hammer and other requirements do not need to be provided with the oil return accumulator 5.

In order to facilitate understanding of the working principle, each oil port of the valve body in the drawings is marked by a letter.

The hammer dropping method comprises the following steps:

the hydraulic station is started and is communicated with an oil way of the hydraulic hammer, then the oil is filled into the oil inlet accumulator 4, a rod cavity of the lifting cylinder 1 is communicated with an oil return pipe of the hydraulic station through an oil outlet B and an oil return port T of the reversing valve 2, and the heavy hammer 6 is positioned at the bottom dead center.

After the reversing valve 2 is reversed, a pressure port P of the reversing valve is communicated with an oil outlet B, a pressure pipe of the hydraulic station and the oil inlet energy accumulator 4 simultaneously supply oil to a rod cavity of the lifting cylinder 1 through the pressure port P and the oil outlet B of the reversing valve 2 to push a piston to move upwards, and the weight 6 compresses the boosting energy accumulator 3 to accumulate energy when lifting.

After the set lifting height is reached, the reversing valve 2 is reset, an oil outlet B of the reversing valve 2 is communicated with an oil return port T, a pressure port P is sealed, the heavy hammer 6 falls down under the combined action of gravity and the stress application energy accumulator 3 in an accelerated mode, oil discharged from a rod cavity of the lifting cylinder 1 is discharged through the oil outlet B of the reversing valve 2 and the oil return port T, and part of discharged hydraulic oil enters the oil return energy accumulator 5 to reduce the liquid flow resistance and improve the falling hammer speed. The hydraulic station charges the oil feed accumulator 4 during the hammer drop.

The rated pressure of the hydraulic station is mostly 32MPa, and the maximum pressure is 35 MPa. When the hammer lifting pressure is 20MPa and the liquid flow resistance is 2MPa, the hydraulic station still has residual force of about 10MPa to compress the gas of the force accumulator 3 and accumulate energy. When the pressure required by the heavy hammer 6 to lift is 20MPa, the area of the rod cavity of the lifting cylinder 1 required by the 40t hydraulic hammer is 200cm²When the weight is lifted to the highest point of 1.5m, the maximum value of the resilience force generated after the force accumulator 3 is compressed is about 200kN, which is theoretically 50% of the gravity of the weight 6.

When the rated pressure of the hydraulic station is fixed, the stress application level can be adjusted by adjusting the diameter of the lifting cylinder 1 and the parameters of the piston rod, the inflation pressure of the stress application energy accumulator 3, the inflation (liquid filling) pressure of the rodless cavity of the lifting cylinder 1 and the like.

Therefore, the present embodiment of the invention has no oil discharge and oil supplement resistance of the rodless cavity; the boosting energy accumulator 3 directly pushes the piston to accelerate downwards by utilizing the energy stored when the heavy hammer 6 is lifted, has obvious boosting effect, and has the functions and the characteristics of improving the drop hammer speed, the impact energy and saving energy.

Example 2

Fig. 2 is a drawing of the present embodiment. This example provides an embodiment of the boost accumulator 3 described in example 1. The device comprises a cylinder body 11, a protection piece 12, an air bag 13, a gland 14, an inflation valve 15, a rodless cavity oil port 16, a piston 17, a rod cavity oil port 18 and a piston rod 19. The upper end of the cylinder body 11 is provided with a mounting surface and a mounting hole of a gland 14, the upper and lower parts of the outer side of the cylinder body are respectively provided with a rodless cavity oil port 16 and a rod cavity oil port 18, a piston 17 and a piston rod 19 assembly are arranged in the inner cavity of the cylinder body 11, a protecting piece 12 is arranged on the piston 17, the protecting piece 12 is a metal or non-metal piece, the lower part of the protecting piece is provided with a concave surface for avoiding the bulge of the piston 17 and the piston rod 19 assembly, the upper part of the protecting piece is a smooth surface, an inflation valve 15 is arranged above the gland 14, an air bag 13 is arranged below the gland 14.

As described in embodiment 1, the rodless chamber of the lift cylinder 1 is sealed after injecting air, nitrogen or hydraulic oil through the rodless chamber oil port 16 of the lift cylinder 1.

In the embodiment, residual air in the rodless cavity is directly utilized, a small amount of hydraulic oil is injected, a small amount of residual oil is always kept between the protection piece 12 and the air bag 13, the piston 17 and the sealing piece thereof are lubricated, and the air bag 13 is protected. The rodless cavity port 16 may not be provided.

The boost energy accumulator 3 of the embodiment utilizes the rodless cavity of the lifting cylinder 1, has simple and reliable structure, can avoid the loss of oil discharging and oil supplementing liquid flow of the rodless cavity of the lifting cylinder 1, and can also obviously improve the boost effect of the drop hammer.

Example 3

Fig. 3 is a drawing of the present embodiment. This example provides an embodiment of the lift cylinder 1 described in example 1. The sealing device comprises a cylinder body 11, a guide sleeve 21, a sealing element I22, a sealing element II 23, a sealing element III 24, a sealing element IV 25, a guide sleeve gland 26 and a piston rod 19. The middle part of the guide sleeve 31 is provided with a radial hole 27, the inner side and the outer side of the radial hole 27 of the matching surface of the guide sleeve 21 and the piston rod 19 are respectively provided with a sealing element I22 and a sealing element IV 25 of the piston rod, the inner side and the outer side of the radial hole 27 of the matching surface of the guide sleeve 21 and the cylinder body 11 are respectively provided with a sealing element II 23 and a sealing element III 24, the positions of the cylinder body 11 corresponding to the radial hole 27 of the guide sleeve 21 are provided with radial holes 28, the radial holes 27 are communicated with the radial holes 28, and the radial holes. The guide sleeve gland 26 is fixed on the end face of the cylinder 11. The guide sleeve gland 26 may take other conventional forms such as being integral with the guide sleeve or being internally threaded onto the end of the externally threaded cylinder 11.

The final velocity was >5m in free fall with a height of 1.5 m. After the hydraulic hammer lifting cylinder adopts effective stress application measures, the average extending speed and the final extending speed of the piston rod are higher than those of a free falling body. The piston rod and the piston rod sealing element rub at high speed and high frequency (30-80 strokes per minute) under high pressure, and the sealing element is easy to damage. To this end, the hydraulic hammer lift cylinder is typically provided with a plurality of piston rod seals. At this time, when the inner seal seals well, the outer seal tends to be damaged by friction or overheat due to lack of oil. The failure of the inner sealing element is accelerated after the outer sealing element is damaged or is deformed due to overheating, and hydraulic oil leaks out.

In order to prevent pollution and ensure safety, hydraulic oil is limited to leak in some construction occasions, once a hydraulic cylinder of an underwater hydraulic hammer leaks, the hydraulic cylinder is difficult to find, the leaked hydraulic oil can be stirred to be fully distributed in the inner cavity of a shell of the hydraulic hammer by a heavy hammer and air flow which reciprocate at high speed in a sealed space, and failure of a monitoring part or mechanical failure can be caused.

In the embodiment, the radial hole 28 arranged on the cylinder body 11 and the radial hole 27 arranged on the guide sleeve 21 are connected with an oil return pipe, so that the piston rod sealing element IV 25 on the outer side of the guide sleeve 21 and the adjacent inner side sealing element I22 can be cooled and lubricated, and the sealing element IV 25 can be opened under the action of oil return resistance or back pressure to enhance the sealing effect.

Therefore, the embodiment improves the reliability of the underwater hydraulic hammer, and can also be used for hydraulic hammers used on land and water and other purpose oil cylinders with requirements on leakage and reliability.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, various changes or modifications may be made by the patentees within the scope of the appended claims, and within the scope of the invention, as long as they do not exceed the scope of the invention described in the claims.

Claims

1. The utility model provides a hydraulic hammer thrust augmentation device, includes the hammer system that falls, and the hammer system that falls includes hydraulic pressure station, lift cylinder (1), switching-over valve (2), thrust augmentation accumulator (3), its characterized in that: the hydraulic lifting cylinder is characterized in that the lifting cylinder (1) is a vertically-arranged double-acting single-piston-rod hydraulic cylinder with a downward piston rod, a heavy hammer (6) is connected to the end of a piston rod of the hydraulic lifting cylinder, a boosting energy accumulator (3) is externally connected to a rodless cavity or a boosting energy accumulator (3) is arranged in the rodless cavity, the reversing valve (2) is a two-position three-way reversing valve, a pressure port is sealed, an oil outlet is communicated with an oil return port, an oil return port is communicated with the oil outlet after reversing, the boosting energy accumulator (3) is an air bag type energy accumulator or a piston type energy accumulator, the pressure pipe of a hydraulic station is connected with the pressure port of the reversing valve (2), the oil return pipe of the hydraulic station is connected with the oil return port of the reversing valve.

2. The hydraulic hammer force boosting device according to claim 1, wherein: the oil inlet energy accumulator (4) is arranged, and the oil inlet energy accumulator (4) is connected with a pressure pipe of the hydraulic station.

3. The hydraulic hammer force boosting device according to claim 1, wherein: the oil return energy accumulator (5) is arranged, and the oil return energy accumulator (5) is connected with an oil return pipe of the hydraulic station.

4. The hydraulic hammer force boosting device according to claim 1, wherein: the reversing valve (2) can be replaced by a two-position four-way reversing valve, a three-position four-way reversing valve and a cartridge valve.

5. The hydraulic hammer force boosting device according to claim 1, wherein: when the hydraulic station is a constant-flow hydraulic system, the pressure port, the oil outlet and the oil return port are normally open when the reversing valve (2) is at a static position.

6. The hydraulic hammer force boosting device according to claim 1, wherein: the boosting energy accumulator (3) arranged in the rodless cavity of the lifting cylinder (1) comprises a cylinder body (11), a protection piece (12), an air bag (13), a gland (14) and an inflation valve (15).

7. The upper end of the cylinder body (11) is provided with a gland (14) mounting surface and a mounting hole, the piston and the piston rod assembly are arranged in the inner cavity of the cylinder body (11), a protection piece (12) is arranged on the piston, the protection piece (12) is a metal or non-metal piece with a concave surface for avoiding the protrusion of the piston and the piston rod assembly and a smooth surface on the upper surface, an inflation valve (15) is arranged above the gland (14), an air bag (13) is arranged below the inflation valve, and the gland (14) is hermetically fixed at the upper end of the cylinder body (11) after the air bag (13) is arranged in the rod.

8. The hydraulic hammer force boosting device according to claim 1, wherein: the boosting energy accumulator (3) arranged in the rodless cavity of the lifting cylinder (1) is a piston type energy accumulator of which an inflation valve (15) is arranged in the rodless cavity of the lifting cylinder (1).

9. The hydraulic hammer force boosting device according to claim 1, wherein: the lifting cylinder (1) comprises a guide sleeve (21), a sealing element I (22), a sealing element II (23), a sealing element III (24), a sealing element IV (25) and a guide sleeve gland (26), wherein a radial hole (27) is formed in the middle of the guide sleeve (21), the sealing element I (22) and the sealing element IV (25) are respectively arranged on the inner side and the outer side of the guide sleeve (21) and the piston rod matching surface radial hole (27), the sealing element II (23) and the sealing element III (24) are respectively arranged on the inner side and the outer side of the guide sleeve (21) and the cylinder body (11) matching surface radial hole (27), and the cylinder body (11) is provided with a radial hole (28) communicated with the guide sleeve (21) radial hole (27);

the guide sleeve gland (26) is fixedly arranged on the end surface of the rod cavity of the cylinder body (21);

a hydraulic hammer force application device and method of operation utilizing the hydraulic hammer force application device of any one of claims 1-4 and 6-8, comprising the steps of:

s1, the hydraulic station is started and is connected with a hydraulic hammer oil way, then liquid is filled into the oil inlet accumulator 4 for energy storage, a rod cavity of the lifting cylinder 1 is communicated with an oil return pipe of the hydraulic station through an oil outlet and an oil return port of the reversing valve 2, and the heavy hammer 6 is positioned at a bottom dead center;

s2, after the reversing valve 2 is reversed, a pressure port of the reversing valve is communicated with an oil outlet, a pressure pipe of the hydraulic station and the oil inlet energy accumulator 4 simultaneously supply oil to a rod cavity of the lifting cylinder 1 through the pressure port and the oil outlet of the reversing valve 2 to push a piston to move upwards, and the weight 6 compresses the boosting energy accumulator 3 while lifting to accumulate energy;

s3, after the set lifting height is reached, the reversing valve 2 resets, the oil outlet of the reversing valve 2 is communicated with the oil return port, the pressure port is sealed, the heavy hammer 6 accelerates to fall under the combined action of gravity and the stress application energy accumulator 3, oil discharged from the rod cavity of the lifting cylinder 1 is discharged through the oil outlet and the oil return port of the reversing valve 2, and the oil return energy accumulator 5 is deposited when the oil discharge resistance is large;

during the hammer drop, the hydraulic station charges the oil inlet accumulator 4 for energy storage.