A vertical hammer testing method for large hydraulic pile hammer

Abstract

The present invention introduces a method for testing the vertical hammer of a large hydraulic pile hammer. The method includes connecting a test tool between the oil outlet and return oil pipelines of a pile hammer power station; starting one of the diesel engines; giving a 20% proportional signal to the proportional variable pump; and adjusting the pressure to the rated working pressure P. A Afterwards, lock the pressure regulating valve; record and calibrate the flow rate Q; when the control height H is reached, adjust the flow regulating valve to restore it to the calibrated flow rate Q; continue to adjust the flow regulating valve to control the flow meter flow rate to no more than Q + Qm, control the hammer core to descend, and complete a test cycle; the hammer core stroke can be increased and tested multiple times to verify the smoothness of the hammer core operation. The present invention calibrates the output flow rate of the power station and, based on the output flow rate, controls the bypass flow rate by controlling the flow control valve on the dedicated debugging tool. This indirectly achieves controlled movement of the hydraulic hammer core, ensures test accuracy, and enables in-factory testing of the hydraulic hammer.

Description

Technical Field

[0001] The invention relates to the technical field of hydraulic pile hammer testing, in particular to a vertical hammer testing method for a large hydraulic pile hammer. Background Art

[0002] A hydraulic pile hammer is a tool used for implanting steel piles during infrastructure construction in areas such as offshore wind power, ports, and cross-sea bridges. Currently, the technology of large-scale hydraulic pile hammers for wind power construction is monopolized by foreign countries. Due to the mature technical means, large-scale hydraulic pile hammers abroad can be installed horizontally in the factory and use special tooling to conduct pre-delivery testing in a horizontal position. The main problem with horizontal testing is that the huge weight of the hammer core in the horizontal position puts huge pressure on the support bearings, and excessive horizontal movement will cause damage to the support bearings. Therefore, the technical requirements have clear requirements on the number of horizontal tests, and each test must not exceed 5 cycles.

[0003] Since the hydraulic pile hammer is a major equipment, comprehensive pre-delivery testing is an important guarantee for the reliable operation of the hydraulic hammer; the main purposes of the test are 1. to test the function of the control valve; 2. to test the function of the position sensor; 3. to test the smoothness of the hammer core operation; 4. to check the sealing performance of the system; under the condition that the factory height and lifting capacity meet the requirements for vertical installation of the hydraulic hammer, the hammer body is assembled vertically in the factory. After assembly, the hammer body is tested in the vertical state. After meeting the test indicators, it can be laid down for transportation, which will save huge costs; at the same time, the supporting linear bearing of the hammer core guide is in a favorable stress state during the vertical test, so it can be tested an unlimited number of times. For this reason, a complete set of vertical hammer testing methods for large hydraulic pile hammers is required. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method for testing a large hydraulic pile hammer vertical hammer, so that the rising and falling speeds of the hammer core can be controlled, thereby solving the technical problems of hydraulic hammer factory testing.

[0005] The technical solution adopted in the present invention is:

[0006] A vertical hammer test method for a large hydraulic pile hammer, comprising the following steps:

[0007] S1: Connect a test tool between the oil outlet and return lines of the hydraulic circuit of the pile hammer power station. The test tool includes a flow control valve and a flow meter connected in series. The inlet of the flow control valve at one end of the test tool is connected to the pipeline after the oil outlet of the proportional variable pump on the oil outlet pipeline. The outlet of the flow meter at the other end of the test tool is connected to the end of the return line. Keep the flow control valve in the closed state.

[0008] S2: Start one of the diesel engines of the power station of the pile hammer, run it at idle speed for 5 minutes, and then speed it up to the working speed of the diesel engine;

[0009] S3: Give a 20% proportional signal to the proportional variable pump on the output pipeline of the power station;

[0010] S4: energize the first solenoid valve on the output pipeline to close it, adjust the pressure regulating valve, observe the pressure gauge, and see that the pressure changes. Adjust the pressure to the rated working pressure P A After that, lock the pressure regulating valve;

[0011] S5: Adjust the flow control valve in the test tool and slowly open it. The flow meter shows an increase in flow. When the pressure gauge shows a decrease, the flow rate increases gradually and steadily and eventually becomes constant. At this point, the output flow of the oil pump is completely returned to the oil tank through the test tool. The flow rate Q is recorded and calibrated. This verifies that the function of the first solenoid valve and the flow output function of the pressure control valve and the oil pump are normal.

[0012] S6: De-energize the first solenoid valve. The pressure on the pressure gauge drops to the circulating pressure Pd. Then, energize the second solenoid valve on the oil return line. The flow meter in the test tool now displays the calibrated flow rate Q. The output flow of the proportional variable pump flows back to the oil tank through the test tool.

[0013] S7: Slowly close the flow control valve in the test tool. During the adjustment process, you can observe that the pressure on the pressure gauge slowly increases. When it increases to the hammer core lifting pressure Pt, the flow value of the flow meter begins to decrease, and the oil begins to enter the hammer to lift the hammer core. The flow meter is controlled to display a stable flow rate Qm not less than the hammer lifting. At the same time, the status of the A / B sensor on the hydraulic pile hammer is observed through the display screen in the control room. During the hammer core lifting process, the A / B sensor display light on the display screen flashes alternately; the hammer core lifting height is controlled to H, and the A / B sensor display light flashes once when the hammer core lifting height is 70mm. The number of flashes of the A / B sensor is counted; after reaching the control height H, adjust the flow control valve to restore it to the calibrated flow rate Q. At this time, the hammer core should be in a relatively static state;

[0014] S8: Continue to adjust the flow control valve to control the flow meter flow rate to be no greater than Q+Qm, control the hammer core to descend, and when it approaches the limit, adjust the flow meter display to no greater than the limit flow rate Qmm at the end of the hammer body. Finally, let the hammer core fall smoothly to the limit position. At this time, one test cycle is completed, verifying the functions of the first solenoid valve, the second solenoid valve, the A / B sensor, the pressure regulating valve, and the system;

[0015] S9: After becoming proficient in the operation, you can increase the hammer core stroke and test it multiple times to verify the smoothness of the hammer core operation. At the same time, maintain it under pressure to determine the sealing performance of the system.

[0016] Due to the adoption of the above technical solution, the present invention has the following advantages:

[0017] The present invention connects the test tool between the oil outlet and return oil pipelines of the power station, calibrates the output flow of the power station, and controls the bypass flow by controlling the flow control valve on the special debugging tool based on the output flow, thereby indirectly realizing the movement of the hydraulic hammer core in a controlled state, ensuring the test accuracy, and realizing the hydraulic hammer testing in the factory. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a connection diagram of the present invention.

[0019] In the figure: 1-diesel engine tank, 2-proportional variable pump, 3-test tool, 4-pressure gauge, 5-pressure regulating valve, 6-back pressure valve, 7-first solenoid valve, 8-second solenoid valve, 9-hammer core, 10-A / B sensor. DETAILED DESCRIPTION

[0020] The present invention will be further explained below with reference to the accompanying drawings and embodiments, which should not be used to limit the scope of protection of the present invention. The purpose of disclosing the present invention is to protect all technical improvements within the scope of the present invention.

[0021] Combined with attachment Figure 1 As shown, one end of the oil outlet pipeline of the hydraulic circuit of the hydraulic pile hammer is connected to the oil outlet of the diesel engine tank, and is connected to the oil inlet of the pile hammer through the proportional variable pump through the first solenoid valve. A pressure gauge is installed on the pipeline between the proportional variable pump and the first solenoid valve; the oil return port of the pile hammer is connected to the oil return port of the diesel engine through the second solenoid valve and the back pressure valve; the inlet end of the pressure regulating valve is connected to the outlet end of the proportional variable pump through a pipeline, and the outlet end of the pressure regulating valve is connected to the outlet end of the back pressure valve through a pipeline.

[0022] Taking a large hydraulic pile hammer with a hammer core mass of 150 tons as an example, the maximum impact energy of the hydraulic pile hammer during operation can reach 3000KJ. Therefore, the key issue in vertical testing is to keep the huge hammer core in a controlled operating posture and control the operating speed so that the hammer core is stable during the lifting process, with a speed controlled at no more than 5mm / s, and the speed when falling is controlled at no more than 5mm / s. When approaching the end, the speed is controlled at no more than 1mm / s. The impact force when the hammer core finally falls on the hammer body is no more than 30KN, which is the safe impact force that the structure can withstand. The specific implementation method is as follows:

[0023] A vertical hammer test method for a large hydraulic pile hammer, comprising the following steps:

[0024] S1: Connect the test tool between the oil outlet and return oil pipelines of the hydraulic circuit of the pile hammer power station. The test tool includes a flow control valve and a flow meter connected in series. The inlet of the flow control valve at one end of the test tool is connected to the pipeline after the oil outlet of the proportional variable pump on the oil outlet pipeline, and the outlet of the flow meter at the other end of the test tool is connected to the end of the return oil pipeline; keep the flow control valve in the closed state.

[0025] S2: Start one of the diesel engines of the power station of the pile hammer, run it at idle speed for 5 minutes, and then speed it up to the working speed of the diesel engine 1500 r / min.

[0026] S3: Give a 20% proportional signal to the proportional variable pump on the oil outlet pipeline of the power station.

[0027] S4: Energize the first solenoid valve on the output pipeline to close it, adjust the pressure regulating valve, observe the pressure gauge, and you can see the pressure changes. After adjusting the pressure to the rated working pressure of 16MPa, lock the pressure regulating valve.

[0028] S5: Adjust the flow control valve in the test tool and open it slowly. The flow meter display will increase. When the pressure display on the pressure gauge drops, the flow increase gradually becomes stable and eventually constant. At this time, the output flow of the oil pump is all returned to the oil tank through the test tool. The flow Q is recorded and calibrated. The calibrated flow Q is 80 L / min. At this time, the function of the first solenoid valve and the flow output function of the pressure regulating valve and the oil pump are verified to be normal.

[0029] S6: De-energize the first solenoid valve. The pressure on the pressure gauge drops to the circulating pressure Pd. Then energize the second solenoid valve on the oil return line. The flow meter in the test tool displays the calibrated flow Q. The output flow of the proportional variable pump flows back to the oil tank through the test tool.

[0030] S7: Slowly close the flow control valve in the test tool. During the adjustment process, you can observe that the pressure on the pressure gauge slowly increases. When it increases to the hammer core lifting pressure Pt, Pt is 13MPa, the flow value of the flow meter begins to decrease, and the oil begins to enter the hammer to lift the hammer core. The display of the flow meter is controlled to be no less than the stable flow rate Qm of the hammer lifting. Qm is 40L / min. At this time, the hammer core lifting speed is no more than 5mm / s. At the same time, the status of the A / B sensor on the hydraulic pile hammer is observed through the display screen in the control room. During the hammer core lifting process, the A / B sensor display light on the display screen flashes alternately; the hammer core lifting height is controlled to be H, and the A / B sensor display light flashes once when the hammer core lifting height is 70mm. Count the number of flashes of the A / B sensor; when the control height H is reached, adjust the flow control valve to restore it to the calibrated flow rate Q. At this time, the hammer core should be in a relatively static state.

[0031] S8: Continue to adjust the flow control valve to control the flow rate of the flow meter so that it is not greater than Q+Qm. At this time, the hammer core descending speed is no more than 5mm / s. Control the hammer core to descend. When it approaches the limit, adjust the flow meter to display no more than the limit flow rate Qmm at the end of the hammer body. Qmm is 87L / min. At this time, the hammer core descending speed is no more than 1mm / s. Finally, make the hammer core fall smoothly to the limit position. At this time, a test cycle is completed, verifying the functions of the first solenoid valve, the second solenoid valve, the A / B sensor, the pressure regulating valve, and the system.

[0032] S9: After becoming proficient in the operation, you can increase the hammer core stroke and test it multiple times to verify the smoothness of the hammer core operation. At the same time, maintain it under pressure to determine the sealing performance of the system.

[0033] The parts not described in detail in this invention are prior art.

[0034] The embodiments selected herein for the purpose of disclosing the invention are presently considered suitable, but it should be understood that the invention is intended to include all variations and modifications of the embodiments that fall within the scope of the concept and invention.

Claims

1. A large hydraulic pile hammer vertical hammer testing method, characterized in that: The specific steps are: S1: Connect a test tool between the oil outlet and return lines of the hydraulic circuit of the pile hammer power station. The test tool includes a flow control valve and a flow meter connected in series. The inlet of the flow control valve at one end of the test tool is connected to the pipeline after the oil outlet of the proportional variable pump on the oil outlet pipeline. The outlet of the flow meter at the other end of the test tool is connected to the end of the return line. Keep the flow control valve in the closed state. S2: Start one of the diesel engines of the power station of the pile hammer, run it at idle speed for 5 minutes, and then speed it up to the working speed of the diesel engine; S3: Give a 20% proportional signal to the proportional variable pump on the oil outlet pipeline of the power station; S4: energize the first solenoid valve on the output pipeline to close it, adjust the pressure regulating valve, observe the pressure gauge, and see that the pressure changes. Adjust the pressure to the rated working pressure P A After that, lock the pressure regulating valve; S5: Adjust the flow control valve in the test tool and slowly open it. The flow meter shows an increase in flow. When the pressure gauge shows a decrease, the flow rate increases gradually and steadily and eventually becomes constant. At this point, the output flow of the oil pump is completely returned to the oil tank through the test tool. The flow rate Q is recorded and calibrated. This verifies that the function of the first solenoid valve and the flow output function of the pressure control valve and the oil pump are normal. S6: De-energize the first solenoid valve. The pressure on the pressure gauge drops to the circulating pressure Pd. Then, energize the second solenoid valve on the oil return line. The flow meter in the test tool now displays the calibrated flow rate Q. The output flow of the proportional variable pump flows back to the oil tank through the test tool. S7: Slowly close the flow control valve in the test tool. During the adjustment process, you can observe that the pressure on the pressure gauge slowly increases. When it increases to the hammer core lifting pressure Pt, the flow value of the flow meter begins to decrease, and the oil begins to enter the hammer to lift the hammer core. The flow meter is controlled to display a stable flow rate Qm not less than the hammer lifting. At the same time, the status of the A / B sensor on the hydraulic pile hammer is observed through the display screen in the control room. During the hammer core lifting process, the A / B sensor display light on the display screen flashes alternately; the hammer core lifting height is controlled to H, and the A / B sensor display light flashes once when the hammer core lifting height is 70mm. The number of flashes of the A / B sensor is counted; after reaching the control height H, adjust the flow control valve to restore it to the calibrated flow rate Q. At this time, the hammer core should be in a relatively static state; S8: Continue to adjust the flow control valve to control the flow meter flow rate to be no greater than Q+Qm, control the hammer core to descend, and when it approaches the limit, adjust the flow meter display to no greater than the limit flow rate Qmm at the end of the hammer body. Finally, let the hammer core fall smoothly to the limit position. At this time, one test cycle is completed, verifying the functions of the first solenoid valve, the second solenoid valve, the A / B sensor, the pressure regulating valve, and the system; S9: After becoming proficient in the operation, you can increase the hammer core stroke and test it multiple times to verify the smoothness of the hammer core operation. At the same time, maintain it under pressure to determine the sealing performance of the system.

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