CN112431823A - Hydraulic oil cylinder internal leakage detection method - Google Patents
Hydraulic oil cylinder internal leakage detection method Download PDFInfo
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- CN112431823A CN112431823A CN202011398930.9A CN202011398930A CN112431823A CN 112431823 A CN112431823 A CN 112431823A CN 202011398930 A CN202011398930 A CN 202011398930A CN 112431823 A CN112431823 A CN 112431823A
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- 239000010720 hydraulic oil Substances 0.000 title claims abstract description 71
- 238000001514 detection method Methods 0.000 title claims abstract description 22
- 239000003921 oil Substances 0.000 claims abstract description 48
- 238000000034 method Methods 0.000 claims abstract description 26
- 230000008569 process Effects 0.000 claims abstract description 8
- 238000012360 testing method Methods 0.000 claims description 7
- 230000008878 coupling Effects 0.000 claims description 4
- 238000010168 coupling process Methods 0.000 claims description 4
- 238000005859 coupling reaction Methods 0.000 claims description 4
- 230000005389 magnetism Effects 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 230000008859 change Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005465 channeling Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B19/00—Testing; Calibrating; Fault detection or monitoring; Simulation or modelling of fluid-pressure systems or apparatus not otherwise provided for
- F15B19/005—Fault detection or monitoring
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/80—Other types of control related to particular problems or conditions
- F15B2211/87—Detection of failures
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Examining Or Testing Airtightness (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The invention discloses a method for detecting internal leakage of a hydraulic cylinder, and belongs to the technical field of hydraulic cylinders. The method comprises the following steps: firstly, after a piston rod extends to any position, an oil pipe of an oil port on the side of a rod cavity of a hydraulic oil cylinder is detached, and a pressure measuring joint I is reserved; the oil through pipeline is connected with an oil port on the side of a rodless cavity of the hydraulic oil cylinder through a pressure measuring connector II; fixing a dial indicator on a piston rod of the hydraulic oil cylinder, wherein a measuring needle head of the dial indicator is tightly attached to the end face of a guide sleeve of the hydraulic oil cylinder; introducing high-pressure hydraulic oil into a rodless cavity of the hydraulic oil cylinder, wherein the hydraulic oil pressure of the rodless cavity is higher than that of the rod cavity; fourthly, continuously introducing high-pressure hydraulic oil to the side of the rodless cavity for a certain time, and observing whether the measuring needle of the dial indicator rotates or not in the process. The invention only needs to add the magnetic dial indicator, reduces the repeated disassembling and assembling procedures, has high detection efficiency and is convenient to operate during detection; the method can detect whether the hydraulic oil cylinder leaks inwards at any middle stroke position, and is convenient for judging the fault position of the hydraulic oil cylinder.
Description
Technical Field
The invention relates to the technical field of hydraulic cylinders, in particular to a method for detecting internal leakage of a hydraulic cylinder.
Background
In the field of engineering machinery, a hydraulic oil cylinder is a key execution element in the working process of a host, and the normal work and the service life are directly influenced by the fault of the hydraulic oil cylinder. The most common failure of a hydraulic oil cylinder is internal leakage, and the main causes of the internal leakage are as follows: the hydraulic system has the advantages that the inner hole of the cylinder barrel of the oil cylinder is damaged due to strain, the sealing of the piston is damaged, the piston and the inner hole of the cylinder barrel are in hard contact due to abnormal unbalance loading force in the working process, parts are damaged, and the like, oil leakage can cause oil channeling of a rodless cavity and a rodless cavity in the working process of the hydraulic oil cylinder, and the performance and the efficiency of the hydraulic system are seriously influenced.
For hydraulic cylinder internal leakage, methods for evaluating leakage in single-acting and double-acting hydraulic cylinders are described in GB/T15622-2005, and the internal leakage test method is defined as "filling the working chamber of the cylinder to be tested, pressurizing to a rated pressure or a pressure specified by a user, and measuring the leakage amount of leakage to the unpressurized chamber via the piston". The method is not described in detail with respect to how the amount of leakage past the piston into the unpressurized chamber is determined and the position of the stroke is measured.
The existing method for detecting the internal leakage amount of the hydraulic cylinder comprises the following steps:
firstly, an oil port of a low-pressure cavity is opened when a piston rod reaches the tail end of a stroke, and the number of drops of hydraulic oil is counted after the leakage amount is stable, wherein each drop is 0.05 mL;
secondly, an oil port of the low-pressure cavity is opened when the piston rod reaches the tail end of the stroke, and the internal leakage amount within a certain time is measured by using a measuring cup after the leakage amount is stable;
and thirdly, judging whether the oil cylinder has internal leakage when the pressure drop value is lower than a certain specified value according to the pressure resistance and pressure maintaining at the tail end of the stroke on the test bed.
The measurement of the methods can only detect whether the two ends of the piston rod leak inwards when reaching the stroke end, but cannot measure whether the hydraulic oil cylinder has the internal leakage defect at any position of the stroke. In addition, in the former two methods, each hydraulic oil cylinder needs to consume a certain time for measurement, the consumed time is long, the measurement efficiency is low, and the labor force is increased; although the 3 rd pressure drop value determination method is relatively intuitive, the pressure drop value cannot completely indicate that the hydraulic oil cylinder has internal leakage, and may be caused by leakage outside the hydraulic oil cylinder or the hydraulic system, and the determination method is difficult to determine whether the hydraulic oil cylinder has internal leakage or not, and cannot accurately obtain the internal leakage amount, so that the detection result of the internal leakage of the hydraulic oil cylinder is not accurate.
Chinese patent discloses a leakage detection tool (CN 202441672U) in a hydraulic oil cylinder, which comprises a connecting pipe, an oil cup and a hollow joint, wherein the oil cup and the hollow joint are arranged at two ends of the connecting pipe and are communicated with the inner cavity of the connecting pipe, the oil cup is transparent or semitransparent, the end of the oil cup, which is far away from the connecting pipe, is open, and the outer wall of the oil cup is provided with scale marks and scale values corresponding to the scale marks respectively along the height direction. The connecting pipe is composed of a first pipe, a second pipe and a third pipe which are respectively and vertically communicated with two ends of the first pipe, the second pipe and the third pipe share the same plane, and the directions of the second pipe and the third pipe are opposite; the oil cup is bonded at the end of the second pipe far away from the first pipe and shares the same center line with the second pipe, and the scale mark corresponding to the zero scale value is positioned at the side of the oil cup close to the first pipe in the height direction; the joint is a bolt with a through hole in the axial direction, and the bolt is adhered to the end, far away from the first pipe, of the third pipe through the screwing end of the bolt and shares the center line with the third pipe. The connecting pipe is a copper pipe, and the oil cup is a glass cup. The detection tool is easy to determine whether the hydraulic oil cylinder has internal leakage or not, and can accurately obtain the leakage amount of the internal leakage, so that the detection result of the internal leakage of the hydraulic oil cylinder is accurate.
The prior art has the following defects:
1. when the detection tool is used for detecting internal leakage, a rod cavity test joint and an oil line oil pipe are required to be removed after the performance test of a hydraulic oil cylinder test bed is completed, then the hydraulic oil cylinder internal leakage detection tool is installed and needs to be kept in a vertical placement state, the influence of repeated dismounting and installation procedures on detection efficiency is increased, in addition, the detection tool needs to be kept in a vertical arrangement state, when the positions of two oil ports of a hydraulic oil cylinder change or are positioned at a certain angle, and external force assistance is required to be added when the detection tool is used for keeping the vertical state;
2. the internal leakage detection tool for the hydraulic oil cylinder is provided with the oil cup, and the internal leakage amount is measured by observing the scale change of the liquid level of the oil cup, but the measuring device is only suitable for measuring the internal leakage amount at two ends of the stroke of the hydraulic cylinder and cannot measure whether the hydraulic oil cylinder leaks at any stroke position in the middle.
Disclosure of Invention
In order to solve the technical problem, the invention provides a hydraulic oil cylinder internal leakage detection method.
The invention is realized by the following technical scheme: a method for detecting internal leakage of a hydraulic oil cylinder comprises the following steps:
firstly, on a hydraulic oil cylinder test platform, after a piston rod extends to any position, an oil pipe of an oil port on the side of a rod cavity of the hydraulic oil cylinder is detached, and a pressure measuring joint I is reserved;
the oil through pipeline is connected with an oil port on the side of a rodless cavity of the hydraulic oil cylinder through a pressure measuring connector II;
fixing a dial indicator on a piston rod of the hydraulic oil cylinder, wherein a measuring needle head of the dial indicator is tightly attached to the end face of a guide sleeve of the hydraulic oil cylinder, and the measuring needle head does not jump;
introducing high-pressure hydraulic oil into a rodless cavity of the hydraulic oil cylinder, wherein the hydraulic oil pressure of the rodless cavity is higher than that of the rod cavity;
fourthly, continuously introducing high-pressure hydraulic oil to the side of the rodless cavity for a certain time, and observing whether the measuring needle of the dial indicator rotates or not and whether the reading of the dial indicator changes or not in the process;
if the pressure is not changed, the hydraulic oil cylinder is not internally leaked;
if the measuring needle head rotates and the reading number of the pointer dial changes, the oil leakage of the two cavities of the rodless cavity and the rod cavity is shown, the extending stroke of the piston rod changes, and the hydraulic oil cylinder leaks.
It further comprises the following steps: the dial indicator is connected with the magnetic base through the adjusting rod.
The bottom surface of the magnetic base is arc-shaped and is matched and adsorbed on the surface of the piston rod; and a locking switch is installed on the magnetic base through threaded connection, and the inner end of the locking switch abuts against the surface of the piston rod.
The adjusting rod comprises a connecting rod I and a connecting rod II; the lower end of the connecting rod I is rotatably connected with the magnetic base, and the lower end of the connecting rod I is locked with the magnetic base through a locking knob I; the upper end of the connecting rod I and the lower end of the connecting rod II are rotatably connected, and the upper end of the connecting rod I and the lower end of the connecting rod II are locked through a locking knob II; rotatable coupling between II upper ends of connecting rod and the pointer dial plate locks through locking knob III between II upper ends of connecting rod and the pointer dial plate.
Compared with the prior art, the invention has the beneficial effects that:
1, an oil passage and a pressure measuring joint of an original hydraulic oil cylinder test platform can be used, only a magnetic dial indicator is needed to be added, repeated disassembling and assembling procedures are reduced, the detection efficiency is high, and the operation is convenient during detection;
2, after the piston rod extends to any stroke position, the dial indicator measures that the needle head is tightly attached to the end face of the guide sleeve, whether the oil cylinder leaks inwards is evaluated by observing whether the pointer of the dial indicator rotates, whether the hydraulic oil cylinder leaks inwards at any middle stroke position can be detected by the method, and the fault position of the hydraulic oil cylinder is convenient to judge.
Drawings
FIG. 1 is a schematic diagram of the process of use of the present invention;
FIG. 2 is a schematic diagram of a dial indicator structure;
in the figure: 1. a connecting rod I; 11. a magnetic base; 12. a locking switch; 13. a locking knob I; 2. a connecting rod II; 21. a locking knob II; 22. locking a knob III; 31. a pointer dial; 32. measuring a needle head; 4. a pressure measuring joint II; 41. a pressure measuring joint I; 51. a rodless cavity side oil port; 52. an oil passage; 6. a side oil port of the rod cavity; 7. a piston rod; 8. a piston rod; 9. and a guide sleeve.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in figures 1 and 2, the internal leakage detection method of the hydraulic oil cylinder uses a dial indicator, a pointer dial 31 of the dial indicator is rotatably connected with the upper end of a connecting rod II 2, and the pointer dial 31 and the upper end of the connecting rod II 2 are locked through a locking knob III 22. Rotatable coupling between I1 upper end of connecting rod and II 2 lower extremes of connecting rod, through locking knob II 21 locking between I1 upper end of connecting rod and II 2 lower extremes of connecting rod. Rotatable coupling between I1 lower extreme of connecting rod and the magnetism base 11 locks through locking knob I13 between I1 lower extreme of connecting rod and the magnetism base 11. The bottom surface of the magnetic base 11 is arc-shaped, and the bottom surface of the magnetic base 11 can be matched and adsorbed on the surface of the piston rod 7. The magnetic base 11 is provided with a locking switch 12 through threaded connection, the inner end of the locking switch 12 abuts against the surface of the piston rod 7, and the magnetic base 11 and the piston rod 7 are positioned by rotating the locking switch 12.
As shown in fig. 1, a method for detecting internal leakage of a hydraulic cylinder includes the following steps:
firstly, on a hydraulic oil cylinder test platform, after a piston rod 7 extends to any position, an oil pipe of an oil port 6 on the side of a rod cavity of the hydraulic oil cylinder is removed, and a pressure measuring joint I41 is reserved;
the oil passage 52 is connected with a rodless cavity side oil port 51 of the hydraulic oil cylinder through a pressure measuring connector II 4;
placing a magnetic base 11 of the dial indicator on a piston rod 8, adsorbing the magnetic base on the surface of the outer circle of the piston rod 8 by virtue of magnetism, adjusting the relative position of a pointer dial 31 of the dial indicator and the magnetic base 11 by virtue of a locking knob III 22, a locking knob II 21 and a locking knob I13, attaching a measuring needle 32 of the dial indicator to the end surface of an oil cylinder guide sleeve 9, locking the magnetic base on the piston rod 8 by rotating a locking switch 12 without rotating or moving and locking each knob, ensuring that the measuring needle of the dial indicator is not jumped when being attached to the end surface of the guide sleeve 9, and recording the indication position reading of the pointer of the dial indicator;
thirdly, high-pressure hydraulic oil is continuously introduced from the oil passage 52, the high-pressure oil in the oil passage 52 enters a rodless cavity in the cylinder barrel 7 of the hydraulic oil cylinder through an oil port 51 on the side of the rodless cavity of the hydraulic oil cylinder, and the hydraulic oil pressure of the rodless cavity is higher than that of the rod cavity at the moment;
fourthly, continuously introducing high-pressure hydraulic oil to the side of the rodless cavity for a certain time, and observing whether the measuring needle head 32 of the dial indicator rotates or not and whether the reading of the pointer dial 31 of the dial indicator changes or not in the process;
if the pressure is not changed, the hydraulic oil cylinder is not internally leaked;
if the measuring needle head 32 rotates and the reading of the pointer dial 31 changes, the oil leakage of the two cavities of the rodless cavity and the rod cavity is shown, the extending stroke of the piston rod 7 changes, and the hydraulic oil cylinder leaks inwards. The method can visually detect whether the hydraulic oil cylinder leaks inwards.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (4)
1. The internal leakage detection method of the hydraulic oil cylinder is characterized by comprising the following steps: the method comprises the following steps:
firstly, on a hydraulic oil cylinder test platform, after a piston rod (7) extends to any position, an oil pipe of an oil port (6) on the side of a rod cavity of the hydraulic oil cylinder is detached, and a pressure measuring joint I (41) is reserved;
the oil passage (52) is connected with a rodless cavity side oil port (51) of the hydraulic oil cylinder through a pressure measuring joint II (4);
fixing the dial indicator on a piston rod (8) of the hydraulic oil cylinder, wherein a measuring needle head (32) of the dial indicator is tightly attached to the end face of a guide sleeve (9) of the hydraulic oil cylinder, and the measuring needle head (32) does not jump;
introducing high-pressure hydraulic oil into a rodless cavity of the hydraulic oil cylinder, wherein the hydraulic oil pressure of the rodless cavity is higher than that of the rod cavity;
fourthly, continuously introducing high-pressure hydraulic oil to the side of the rodless cavity for a certain time, observing whether a measuring needle head (32) of the dial indicator rotates or not and whether the reading of a pointer dial plate (31) of the dial indicator changes or not in the process;
if the pressure is not changed, the hydraulic oil cylinder is not internally leaked;
if the measuring needle head (32) rotates and the reading of the pointer dial plate (31) changes, oil leakage of the two cavities of the rodless cavity and the rod cavity is indicated, the extending stroke of the piston rod (7) changes, and the hydraulic oil cylinder leaks inwards.
2. The hydraulic cylinder internal leakage detection method according to claim 1, characterized in that: the dial indicator is connected with a magnetic base (11) through an adjusting rod.
3. The hydraulic cylinder internal leakage detection method according to claim 2, characterized in that: the bottom surface of the magnetic base (11) is arc-shaped, and the bottom surface of the magnetic base (11) is matched and adsorbed on the surface of the piston rod (7); and a locking switch (12) is installed on the magnetic base (11) through threaded connection, and the inner end of the locking switch (12) abuts against the surface of the piston rod (7).
4. The hydraulic cylinder internal leakage detection method according to claim 2, characterized in that: the adjusting rod comprises a connecting rod I (1) and a connecting rod II (2); the lower end of the connecting rod I (1) is rotatably connected with the magnetic base (11), and the lower end of the connecting rod I (1) is locked with the magnetic base (11) through a locking knob I (13); the upper end of the connecting rod I (1) is rotatably connected with the lower end of the connecting rod II (2), and the upper end of the connecting rod I (1) is locked with the lower end of the connecting rod II (2) through a locking knob II (21); rotatable coupling between II (2) upper end of connecting rod and pointer dial plate (31), through locking knob III (22) locking between II (2) upper end of connecting rod and pointer dial plate (31).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011398930.9A CN112431823A (en) | 2020-12-04 | 2020-12-04 | Hydraulic oil cylinder internal leakage detection method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011398930.9A CN112431823A (en) | 2020-12-04 | 2020-12-04 | Hydraulic oil cylinder internal leakage detection method |
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| CN112431823A true CN112431823A (en) | 2021-03-02 |
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| CN202011398930.9A Pending CN112431823A (en) | 2020-12-04 | 2020-12-04 | Hydraulic oil cylinder internal leakage detection method |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202441672U (en) * | 2012-02-20 | 2012-09-19 | 蚌埠液力机械有限公司 | Inner leakage detection tool for hydraulic oil cylinder |
| CN102865271A (en) * | 2012-09-28 | 2013-01-09 | 天津鼎成高新技术产业有限公司 | Detection method and device of internal leakage of hydraulic valve |
| CN203321939U (en) * | 2013-05-27 | 2013-12-04 | 徐州力成液压设备有限公司 | Hydraulic cylinder internal leakage composite detection system |
| CN109356910A (en) * | 2018-09-13 | 2019-02-19 | 上海宝钢工业技术服务有限公司 | The test macro and method of position internal leakage in hydraulic cylinder |
| CN209976973U (en) * | 2019-04-24 | 2020-01-21 | 中铁二十四局集团有限公司 | Detection device for rapidly detecting internal leakage of hydraulic oil cylinder |
-
2020
- 2020-12-04 CN CN202011398930.9A patent/CN112431823A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN202441672U (en) * | 2012-02-20 | 2012-09-19 | 蚌埠液力机械有限公司 | Inner leakage detection tool for hydraulic oil cylinder |
| CN102865271A (en) * | 2012-09-28 | 2013-01-09 | 天津鼎成高新技术产业有限公司 | Detection method and device of internal leakage of hydraulic valve |
| CN203321939U (en) * | 2013-05-27 | 2013-12-04 | 徐州力成液压设备有限公司 | Hydraulic cylinder internal leakage composite detection system |
| CN109356910A (en) * | 2018-09-13 | 2019-02-19 | 上海宝钢工业技术服务有限公司 | The test macro and method of position internal leakage in hydraulic cylinder |
| CN209976973U (en) * | 2019-04-24 | 2020-01-21 | 中铁二十四局集团有限公司 | Detection device for rapidly detecting internal leakage of hydraulic oil cylinder |
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Application publication date: 20210302 |