US20130202362A1 - Pile driver with air pressure buffer - Google Patents
Pile driver with air pressure buffer Download PDFInfo
- Publication number
- US20130202362A1 US20130202362A1 US13/640,680 US201113640680A US2013202362A1 US 20130202362 A1 US20130202362 A1 US 20130202362A1 US 201113640680 A US201113640680 A US 201113640680A US 2013202362 A1 US2013202362 A1 US 2013202362A1
- Authority
- US
- United States
- Prior art keywords
- pile
- buffer
- air pressure
- piston
- compressed gas
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D7/00—Methods or apparatus for placing sheet pile bulkheads, piles, mouldpipes, or other moulds
- E02D7/02—Placing by driving
- E02D7/06—Power-driven drivers
- E02D7/10—Power-driven drivers with pressure-actuated hammer, i.e. the pressure fluid acting directly on the hammer structure
Definitions
- the present invention relates to a liquid propellant pile driver's design and improves the piling principle and the structure of the pile driver buffer.
- the present invention is the improvement of the original invention “Liquid Propellant Pile Driver” (Application No.: CN87108193.8; Pub. No.: CN1033532).
- the original invention introduced a new kind of pile driver that uses liquid propellants as its piling energy.
- the liquid propellants combust in the combustion chamber and produce forces to push the pile into the ground through a piston lever and generate the first piling.
- a liquid buffer is used for absorbing the falling energy of the rebound part and producing piling force and forming the second piling.
- the inadequacy is that: a great quantity of heat is produced and the energy is wasted.
- the purpose of this invention is to overcome the inadequacy of the original invention “Liquid Propellant Pile Driver” and avoids producing the heat and wasting the energy when the liquid buffer absorbs the fall energy of the rebound part.
- the present invention uses air pressure buffer to replace the original liquid buffer.
- the piling principle is changed from almost fully plastic impact piling mode to more like a perfectly elastic impact piling mode. Accordingly, the liquid propellant pile drive with the air pressure buffer consumes less energy and has faster piling frequency.
- the structure of the air pressure buffer is that: at the lower portion of the pile driver, there is a buffer cylinder in which a buffer piston can move up and down; the buffer piston, buffer cylinder and a vessel which connected to the buffer cylinder form a sealed space; The space contains compressed gases or a gasbag that contains compressed gases; The buffer piston can be pressed down and forms a compressed gas spring.
- the rebound part of the pile driver When the rebound part of the pile driver falls down, it compresses the compressed gas spring. During the compressed gas spring being compressed, the energy of motion is used up and the rigid impact is avoided. Because the force of the compressed gas spring is far greater than the weight of the rebound part of the pile driver, when the compressed gas spring rebounds, it pushes the rebound part up and transfers the compressed spring potential energy to the rebound part again in order to reserve the energy for next piling. Because the acting force equals to the reacting force but acting on opposite directions, the compressed gas spring produces the press force on the pile and pushes the pile into ground while the compressed gas spring is compressed and rebounding. Because it is more like a perfectly elastic impact during the compressed gas spring being compressed, the energy lost is less, and less heat is produced. The energy consume of piling is reduced. Another advantage is realizing multi hits by one ignition.
- the buffering force of the compressed gas spring can be adjusted.
- Method one is adjusting the pre-loaded pressure of the gases in the buffer by pumping in or out the gases.
- Method two is adjusting the pre-loaded pressure of the gases in the buffer by pumping in or out the liquid.
- the liquid in the buffer also plays the roles of sealing and lubricating.
- FIG. 1 is the overall drawing of the liquid propellant pile driver and the pile, used to indicate the location of the pile driver buffer.
- FIG. 2 is the section view of the buffer and related parts in an embodiment.
- the piston lever 7 , the pile cap 2 and the pile 1 in the low part of the liquid propellant pile driver are connected together and are supported by the soil underneath.
- the rest parts of the pile driver belong to the rebound part.
- FIG. 2 shows the various parts of the buffer at the stationary equilibrium position.
- the compressed gas 8 in the vessel 5 push the buffer piston 3 to the low dead end.
- the weight of the rebound part passes to the pile cap 2 and the pile 1 through the surface of the anti-collision opening cylinder 9 in the buffer piston 3 .
- the first piling is done by the same methods as original design.
- the liquid propellants combust in the combustion chamber and produce forces.
- the forces push the pile 1 into the ground through the piston lever 7 and push the rebound part moving upward.
- the second piling is done by this invention however:
- the buffer piston 3 contacts the boss of the pile cap 2 , and its moving speed is as the same speed as the pile cap 2 quickly. Because the rebound part's speed is faster than the speed of the pile cap 2 and pile 1 , the buffer piston 3 separates oneself from the surface of the low dead end and starts sliding in the buffer cylinder 4 , that compresses the compressed gas 8 further.
- the forces generated by the compressed gas 8 push down the pile 1 into ground and push up the rebound part and reduce its falling speed in order to avoid the rigid collision.
- the falling down kinetic energy of the rebound part is transformed into potential energy of the compressed gas spring.
- the advantages of using air pressure buffer are less energy consume and less heat generation in the buffer. Because the heat dissipation of the gas spring is very small in the fast compression and rebound, it is a good elastomer with high rebound ratio. It converts the falling down kinetic energy of the rebound part of the pile driver partially into useful work for sinking the pile and a part of the kinetic energy is returned to and raises the rebound part and can be used again in the next hit. The energy consumes in the heat is very small.
- the original hydraulic buffer converts the kinetic energy into thermal energy, and absorbs the kinetic energy of the rebound part without rebound. When the piling resistance is growing larger and larger, the energy consumes in the hydraulic buffer becomes more and more. So that liquid temperature in the liquid buffer rises too high and too fast to work properly.
- this elastic buffering method Because this elastic buffering method is used, the fuel consumed in the piling process reduces greatly. The maximum amount of the fuel injected is only one third of the original design. Not only the combustion chamber pressure is reduced, but also the heat generation in the combustion chamber is reduced. The piling force lasts longer. Because this elastic buffering method will produce pressure to the pile during compressing and extending, the piling time is as twice as longer than that of hydraulic buffer. The impulse has doubled so that the pile's penetration has more than doubled. The piling force on the pile is also more stable. The piling force is relatively even.
- the piling force only relates to the volume and pressure of the compressed gas 8 in the vessel 5 and the compressed distance of travel of the buffer piston 3 , but does not directly relate to the geological conditions, the weight, elasticity and the depth of the pile.
- the gas pressure can be adjusted according to piling requirements for piling in the best state, increasing piling speed and ensuring piling quality.
- Adversely, the hydraulic buffer's piling force is great influenced by the piling condition and geological conditions and more difficult to adjust.
- the piling frequency is higher because the rebound part rebounds immediately after hit the pile without dwell time, and the rebound part bounces up and down freely under the gravity.
- the original design needs a dwell and stilling time after the rebound part falling down for liquid propellants being injected and ignited. It takes longer time and realizes twice pilings by one ignition only.
- the present design using the air pressure buffer instead of the original hydraulic buffer can achieve multi pilings by one ignition.
- the piling resistance is big, the energy consumed in the pile is small. Most of the kinetic energy of the rebound part is rebounded. If the fuels are injected and ignited each time, the rebound part of the pile driver will jump higher and higher and finally exceed the permitted range.
- the air pressure buffer can provides much larger piling forces than conventional spring without fatigue failure.
- the function of the anti-collision opening cylinder 9 in the low part of the buffer piston 3 is to avoid the rigid collision between the buffer piston 3 and the boss of the pile cap 2 .
- the gases in the anti-collision opening cylinder 9 act as an air cushion.
- the gases in the anti-collision opening cylinder 9 are compressed before the buffer piston 3 contacts the boss of the pile cap 2 , and produce a sufficient force to push the buffer piston 3 start moving in the buffer cylinder 4 .
- the air pressure buffer can remain keep part of functions of the hydraulic buffer.
- the hydraulic buffer begins to function to absorb excessive amount energy of the rebound part, avoid damages and maintain normal operation.
- the present invention provides a air pressure buffer for replacing the liquid buffer on the liquid propellant pile driver.
- the piling mode is more like a perfectly elastic impact rather than a fully plastic impact, in order to save energy and acquire faster piling frequency.
- the present invention is suitable for industry application.
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Paleontology (AREA)
- Civil Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Placing Or Removing Of Piles Or Sheet Piles, Or Accessories Thereof (AREA)
Abstract
A pile driver with an air pressure buffer comprises a pile following moving part, a rebound part, and an air pressure buffer. The pile following moving part comprises a pile cap (2) contacting the pile (1) and a piston lever (7), and the rebound part is the other part except the moving part. An air pressure buffer provided between the moving part and the rebound part is composed of a buffer piston (3), a buffer cylinder (4) and a vessel (5). The buffer cylinder (4) and the vessel (5) are intercommunicated with each other. Compressed gas (8) is filled in the vessel (5). The buffer piston (3) can slide in the buffer cylinder (4). The pile driver can save energy and accelerate the frequency of driving pile.
Description
- The present invention relates to a liquid propellant pile driver's design and improves the piling principle and the structure of the pile driver buffer.
- The present invention is the improvement of the original invention “Liquid Propellant Pile Driver” (Application No.: CN87108193.8; Pub. No.: CN1033532). The original invention introduced a new kind of pile driver that uses liquid propellants as its piling energy. The liquid propellants combust in the combustion chamber and produce forces to push the pile into the ground through a piston lever and generate the first piling. A liquid buffer is used for absorbing the falling energy of the rebound part and producing piling force and forming the second piling. However, the inadequacy is that: a great quantity of heat is produced and the energy is wasted.
- The purpose of this invention is to overcome the inadequacy of the original invention “Liquid Propellant Pile Driver” and avoids producing the heat and wasting the energy when the liquid buffer absorbs the fall energy of the rebound part.
- The present invention uses air pressure buffer to replace the original liquid buffer. The piling principle is changed from almost fully plastic impact piling mode to more like a perfectly elastic impact piling mode. Accordingly, the liquid propellant pile drive with the air pressure buffer consumes less energy and has faster piling frequency.
- The structure of the air pressure buffer is that: at the lower portion of the pile driver, there is a buffer cylinder in which a buffer piston can move up and down; the buffer piston, buffer cylinder and a vessel which connected to the buffer cylinder form a sealed space; The space contains compressed gases or a gasbag that contains compressed gases; The buffer piston can be pressed down and forms a compressed gas spring.
- When the rebound part of the pile driver falls down, it compresses the compressed gas spring. During the compressed gas spring being compressed, the energy of motion is used up and the rigid impact is avoided. Because the force of the compressed gas spring is far greater than the weight of the rebound part of the pile driver, when the compressed gas spring rebounds, it pushes the rebound part up and transfers the compressed spring potential energy to the rebound part again in order to reserve the energy for next piling. Because the acting force equals to the reacting force but acting on opposite directions, the compressed gas spring produces the press force on the pile and pushes the pile into ground while the compressed gas spring is compressed and rebounding. Because it is more like a perfectly elastic impact during the compressed gas spring being compressed, the energy lost is less, and less heat is produced. The energy consume of piling is reduced. Another advantage is realizing multi hits by one ignition.
- The buffering force of the compressed gas spring can be adjusted. Method one is adjusting the pre-loaded pressure of the gases in the buffer by pumping in or out the gases.
- Method two is adjusting the pre-loaded pressure of the gases in the buffer by pumping in or out the liquid. The liquid in the buffer also plays the roles of sealing and lubricating.
-
FIG. 1 is the overall drawing of the liquid propellant pile driver and the pile, used to indicate the location of the pile driver buffer. -
FIG. 2 is the section view of the buffer and related parts in an embodiment. - In the drawing: 1. pile, 2. pile cap, 3. buffer piston, 4. buffer cylinder, 5. vessel, 6. liquid, 7. piston lever, 8. compressed gas, 9. anti-collision opening cylinder.
- The piston lever 7, the
pile cap 2 and the pile 1 in the low part of the liquid propellant pile driver are connected together and are supported by the soil underneath. The rest parts of the pile driver belong to the rebound part. -
FIG. 2 shows the various parts of the buffer at the stationary equilibrium position. The compressedgas 8 in the vessel 5 push the buffer piston 3 to the low dead end. The weight of the rebound part passes to thepile cap 2 and the pile 1 through the surface of the anti-collision opening cylinder 9 in the buffer piston 3. - The first piling is done by the same methods as original design. The liquid propellants combust in the combustion chamber and produce forces. The forces push the pile 1 into the ground through the
piston lever 7 and push the rebound part moving upward. - The second piling is done by this invention however: When the rebound part fall down from a height, the buffer piston 3 contacts the boss of the
pile cap 2, and its moving speed is as the same speed as thepile cap 2 quickly. Because the rebound part's speed is faster than the speed of thepile cap 2 and pile 1, the buffer piston 3 separates oneself from the surface of the low dead end and starts sliding in thebuffer cylinder 4, that compresses the compressedgas 8 further. The forces generated by thecompressed gas 8 push down the pile 1 into ground and push up the rebound part and reduce its falling speed in order to avoid the rigid collision. The falling down kinetic energy of the rebound part is transformed into potential energy of the compressed gas spring. When the speed of the rebound part is equal to the speed of the pile 1, the compressing distance of the buffer piston 3 in thebuffer cylinder 4 reaches the maximum. Then the compressed gas spring starts extending, pushes the rebound part moving upward and pushes the pile 1 into ground through the buffer piston 3, thepile cap 2, and the pile 1. When the compressed gas spring extends completely, the buffer piston 3 moves to the low dead end and stops. The rebound part continues moving upward under the effect of inertia. The buffer piston 3 and the boss on the top of thepile cap 2 disengage. The piling force produced by gas pressure disappears. The second piling is finished. - The advantages of using air pressure buffer are less energy consume and less heat generation in the buffer. Because the heat dissipation of the gas spring is very small in the fast compression and rebound, it is a good elastomer with high rebound ratio. It converts the falling down kinetic energy of the rebound part of the pile driver partially into useful work for sinking the pile and a part of the kinetic energy is returned to and raises the rebound part and can be used again in the next hit. The energy consumes in the heat is very small. The original hydraulic buffer converts the kinetic energy into thermal energy, and absorbs the kinetic energy of the rebound part without rebound. When the piling resistance is growing larger and larger, the energy consumes in the hydraulic buffer becomes more and more. So that liquid temperature in the liquid buffer rises too high and too fast to work properly. Because this elastic buffering method is used, the fuel consumed in the piling process reduces greatly. The maximum amount of the fuel injected is only one third of the original design. Not only the combustion chamber pressure is reduced, but also the heat generation in the combustion chamber is reduced. The piling force lasts longer. Because this elastic buffering method will produce pressure to the pile during compressing and extending, the piling time is as twice as longer than that of hydraulic buffer. The impulse has doubled so that the pile's penetration has more than doubled. The piling force on the pile is also more stable. The piling force is relatively even. The piling force only relates to the volume and pressure of the
compressed gas 8 in the vessel 5 and the compressed distance of travel of the buffer piston 3, but does not directly relate to the geological conditions, the weight, elasticity and the depth of the pile. The gas pressure can be adjusted according to piling requirements for piling in the best state, increasing piling speed and ensuring piling quality. Adversely, the hydraulic buffer's piling force is great influenced by the piling condition and geological conditions and more difficult to adjust. - The piling frequency is higher because the rebound part rebounds immediately after hit the pile without dwell time, and the rebound part bounces up and down freely under the gravity. Adversely, the original design needs a dwell and stilling time after the rebound part falling down for liquid propellants being injected and ignited. It takes longer time and realizes twice pilings by one ignition only. The present design using the air pressure buffer instead of the original hydraulic buffer can achieve multi pilings by one ignition. When the piling resistance is big, the energy consumed in the pile is small. Most of the kinetic energy of the rebound part is rebounded. If the fuels are injected and ignited each time, the rebound part of the pile driver will jump higher and higher and finally exceed the permitted range. At this situation, the liquid propellant injections and ignitions will be stopped until the rebound height is reduced to the allowed range step by step. That is an example of multi pilings by one ignition. It is helpful to save fuel, to improve the cooling and lubrication of the combustion chamber, to reduce the exhaust noise and increase the life time of the components. The air pressure buffer can provides much larger piling forces than conventional spring without fatigue failure.
- The function of the anti-collision opening cylinder 9 in the low part of the buffer piston 3 is to avoid the rigid collision between the buffer piston 3 and the boss of the
pile cap 2. The gases in the anti-collision opening cylinder 9 act as an air cushion. The gases in the anti-collision opening cylinder 9 are compressed before the buffer piston 3 contacts the boss of thepile cap 2, and produce a sufficient force to push the buffer piston 3 start moving in thebuffer cylinder 4. - For safety, the present design, the air pressure buffer can remain keep part of functions of the hydraulic buffer. When the air pressure buffer can not absorb the full energy generated by the rebound part, the hydraulic buffer begins to function to absorb excessive amount energy of the rebound part, avoid damages and maintain normal operation.
- The present invention provides a air pressure buffer for replacing the liquid buffer on the liquid propellant pile driver. In the piling principle, the piling mode is more like a perfectly elastic impact rather than a fully plastic impact, in order to save energy and acquire faster piling frequency. The present invention is suitable for industry application.
Claims (2)
1. A liquid propellant pile driver, wherein it comprises
an air pressure buffer or a compressed gas spring which is located in the lower part of the pile driver;
the air pressure buffer or the compressed gas spring is configurated between the rebound part and the parts moving with the pile;
the parts moving with the pile said above include the pile cap that is contacted with the pile and the piston lever that is contacted with the pile without relative motion to the pile;
the rebound part said above includes all the components of the pile driver capable of moving up and down during piling but excludes the parts moving with the pile;
the air pressure buffer or the compressed gas spring said above includes the buffer piston, the buffer cylinder and the vessel; The buffer cylinder is connected to vessel; the vessel said above is filled with compressed gas or has a gasbag that contains compressed gases; the buffer piston can slide in the buffer cylinder.
2. The pile driver described according to claim 1 , wherein it further comprises an anti-collision opening cylinder which is configurated in the low part of the buffer piston of said the air pressure buffer or compressed gas spring
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN 201020151821 CN201891117U (en) | 2010-04-07 | 2010-04-07 | Buffer for pile driver |
CN201020151821.2 | 2010-04-07 | ||
PCT/CN2011/000602 WO2011124090A1 (en) | 2010-04-07 | 2011-04-07 | Pile driver with air pressure buffer |
Publications (1)
Publication Number | Publication Date |
---|---|
US20130202362A1 true US20130202362A1 (en) | 2013-08-08 |
Family
ID=44220595
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US13/640,680 Abandoned US20130202362A1 (en) | 2010-04-07 | 2011-04-07 | Pile driver with air pressure buffer |
Country Status (3)
Country | Link |
---|---|
US (1) | US20130202362A1 (en) |
CN (1) | CN201891117U (en) |
WO (1) | WO2011124090A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115233649A (en) * | 2022-08-31 | 2022-10-25 | 中国路桥工程有限责任公司 | Large-area foundation soil reinforced hydraulic tamper |
Families Citing this family (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104652433B (en) * | 2015-02-25 | 2016-09-07 | 河北鸿德塑料五金制品有限公司 | Pneumatic driver |
CN105882776B (en) * | 2016-04-22 | 2017-11-14 | 哈尔滨工业大学深圳研究生院 | A kind of gas driven jump device |
CN108086317A (en) * | 2017-12-20 | 2018-05-29 | 安徽吉思特智能装备有限公司 | A kind of noise abatement rebound structure of hydraulic hammer |
CN109403322B (en) * | 2018-10-30 | 2020-08-14 | 广东正上工程管理有限公司 | Building foundation tamping method |
WO2020153838A1 (en) * | 2019-01-21 | 2020-07-30 | Itrec B.V. | Pile driving methods and systems for driving a pile |
NL2025191B1 (en) * | 2019-06-28 | 2021-05-31 | Ihc Holland Ie Bv | Pile-driver and method |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4601349A (en) * | 1982-02-06 | 1986-07-22 | Ihc Holland Nv | Hydraulic pile driver |
US5727639A (en) * | 1996-03-11 | 1998-03-17 | Lee Matherne | Pile driving hammer improvement |
US6378951B1 (en) * | 1997-07-23 | 2002-04-30 | Hydroacoustics, Inc. | Vibratory pavement breaker |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1034189C (en) * | 1987-12-14 | 1997-03-05 | 郭伟 | Pile driver powered by liquid explosive |
JP2003082663A (en) * | 2001-09-11 | 2003-03-19 | Chubu Electric Power Co Inc | Pile driving equipment |
CN1167855C (en) * | 2002-07-22 | 2004-09-22 | 周荣珍 | Pile-driving hydraulic hammer |
JP4886068B2 (en) * | 2008-06-04 | 2012-02-29 | 株式会社東亜利根ボーリング | Shock absorber shock absorber |
KR100932662B1 (en) * | 2008-10-17 | 2009-12-21 | 권태운 | Pile driving hammer |
-
2010
- 2010-04-07 CN CN 201020151821 patent/CN201891117U/en not_active Expired - Lifetime
-
2011
- 2011-04-07 WO PCT/CN2011/000602 patent/WO2011124090A1/en active Application Filing
- 2011-04-07 US US13/640,680 patent/US20130202362A1/en not_active Abandoned
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4601349A (en) * | 1982-02-06 | 1986-07-22 | Ihc Holland Nv | Hydraulic pile driver |
US5727639A (en) * | 1996-03-11 | 1998-03-17 | Lee Matherne | Pile driving hammer improvement |
US6378951B1 (en) * | 1997-07-23 | 2002-04-30 | Hydroacoustics, Inc. | Vibratory pavement breaker |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115233649A (en) * | 2022-08-31 | 2022-10-25 | 中国路桥工程有限责任公司 | Large-area foundation soil reinforced hydraulic tamper |
Also Published As
Publication number | Publication date |
---|---|
CN201891117U (en) | 2011-07-06 |
WO2011124090A1 (en) | 2011-10-13 |
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Owner name: GUO, DAVID WEI, CONNECTICUT Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:JIANG, XI;GUO, XINSHENG;REEL/FRAME:029921/0597 Effective date: 20121023 |
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