CN114674278A - Piston rod settlement monitoring system with threshold shielding function - Google Patents
Piston rod settlement monitoring system with threshold shielding function Download PDFInfo
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- CN114674278A CN114674278A CN202210417389.4A CN202210417389A CN114674278A CN 114674278 A CN114674278 A CN 114674278A CN 202210417389 A CN202210417389 A CN 202210417389A CN 114674278 A CN114674278 A CN 114674278A
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- 238000012544 monitoring process Methods 0.000 title claims abstract description 32
- 238000006073 displacement reaction Methods 0.000 claims abstract description 66
- 238000004458 analytical method Methods 0.000 claims abstract description 6
- 238000012545 processing Methods 0.000 claims description 39
- 238000007405 data analysis Methods 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 2
- 238000005259 measurement Methods 0.000 abstract description 2
- 238000013480 data collection Methods 0.000 abstract 1
- 239000000523 sample Substances 0.000 description 5
- 238000002955 isolation Methods 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000009191 jumping Effects 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000004062 sedimentation Methods 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C5/00—Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
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- Testing Of Devices, Machine Parts, Or Other Structures Thereof (AREA)
Abstract
The invention discloses a piston rod settlement monitoring system with a threshold shielding function, and relates to the field of compressors. Its technical scheme main points include according to the angle signal that bent axle position sensor sent, data collection station sends the collection instruction to piston rod position sensor, carries out continuous measurement to the displacement value that sinks of piston rod in 360 rotation periods of bent axle for the displacement value that sinks of piston rod corresponds with the angle of bent axle. The invention has the threshold shielding function, can avoid unnecessary halt and can perform trend analysis and prejudgment on the settlement of the piston rod.
Description
Technical Field
The invention relates to the field of compressors, in particular to a piston rod settlement monitoring system with a threshold shielding function.
Background
For the reciprocating piston compressor, the piston part of the reciprocating piston compressor always reciprocates in the cylinder, and as most of the weight of the piston part acts on the supporting ring, the supporting ring is worn greatly after long-term use, so that the axis of the piston part deviates from the center and is contacted with other parts to cause the damage of a piston rod, a cylinder sleeve and a packing part. In order to solve the problems, the scheme adopted at present is to monitor the sinking amount of the piston rod and give an alarm for prompting.
For example, an eddy current displacement sensor is mounted on the outer side of a flange of a cylinder stuffing box, and whether the piston rod sinks or not is judged by monitoring the change of the distance (Y value) between a sensor probe and the surface of the piston rod. When the probe is arranged above the outer side of the flange, and the monitored distance (Y value) is increased to a certain value, an alarm signal is sent out; when the probe is arranged below the outer side of the flange, the monitored distance (Y value) is reduced to a certain numerical value, and then an alarm signal is sent out. Similar structures are disclosed in, for example, patents assigned publication numbers CN203009264U, CN207686955U, CN211085093U, and CN 20883171U.
However, because a gap exists between the piston and the cylinder, the stress states of the piston and the piston rod can also change, and therefore a certain jumping amount exists in the reciprocating motion process of the piston rod. Meanwhile, during operation, impurities such as tar, catalyst powder and the like entrained in the compressed medium may adhere to the surface of the piston rod or the sensor probe.
Both of these reasons can trigger false alarms, resulting in unnecessary shutdowns, since the probe can only monitor and record one isolated measurement site.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a piston rod settlement monitoring system with a threshold shielding function, which has the threshold shielding function, can avoid unnecessary halt and can perform trend analysis and prejudgment on the settlement of a piston rod.
In order to achieve the purpose, the invention provides the following technical scheme:
a piston rod degradation monitoring system with threshold shielding, comprising:
the piston rod position sensor is used for continuously acquiring a sinking displacement value of the piston rod;
the data acquisition unit is connected with the piston rod position sensor;
the crankshaft position sensor is used for acquiring the angle of a crankshaft;
the data processing unit is respectively connected with the data acquisition unit and the crankshaft position sensor;
the data server is connected with the data processing unit; and the number of the first and second groups,
the industrial personal computer is connected with the data server;
according to the angle signal sent by the crankshaft position sensor, the data acquisition unit sends an acquisition instruction to the piston rod position sensor, and continuously measures the sinking displacement value of the piston rod in a 360-degree rotation period of the crankshaft, so that the sinking displacement value of the piston rod corresponds to the angle of the crankshaft.
Furthermore, a limit value of the sinking displacement value of the piston rod is arranged in the data processing unit, the data processing unit compares the received sinking displacement value with the limit value, and the sinking displacement value reaching or exceeding the limit value is defined as an over-limit value; the over-limit value is used as a monitoring basis for the data processing unit to send out an alarm signal;
defining an isolated over-limit value which does not accord with the change trend of the sinking displacement value and appears in the rotation period of the crankshaft as an isolated threshold value; the isolated threshold value is not used as a monitoring basis for the data processing unit to send out an alarm signal.
Furthermore, a limit value of the sinking displacement value of the piston rod is arranged in the data processing unit, the data processing unit compares the received sinking displacement value with the limit value, and the sinking displacement value reaching or exceeding the limit value is defined as an over-limit value;
when the exceeding limit value occurs in at least two continuous crankshaft rotation periods, the data processing unit sends out an alarm signal.
Furthermore, the data processing unit only emits an alarm signal when the limit value is exceeded in at least five consecutive crankshaft rotation cycles.
Further, the data processing unit compares the received sinking displacement value with the sinking displacement value of the previous crankshaft rotation period, and sends out an early warning signal or an alarm signal according to the comparison result;
when the early warning signal is sent out, the compressor can still continue to work, and when the early warning signal is sent out, the compressor needs to stop working.
Further, the comparison result includes a difference value of the sink displacement values, or a rate of change of the difference value of the sink displacement values.
Further, a data analysis module is arranged in the industrial personal computer and comprises a module for performing trend analysis on the sinking displacement values of different crankshaft rotation periods.
Further, the piston rod position sensor includes an upper piston rod position sensor and a lower piston rod position sensor which are oppositely arranged on the upper side and the lower side of the piston rod, respectively.
Furthermore, the sinking displacement value collected by the upper piston rod position sensor is compared with the sinking displacement value collected by the lower piston rod position sensor, and the coincidence value is taken as the monitoring basis.
Furthermore, the data acquisition unit is connected with a plurality of piston rod position sensors.
In conclusion, the invention has the following beneficial effects:
1. the sinking displacement value of the piston rod corresponds to the angle of the crankshaft, and the sinking displacement value can be periodically and accurately measured, monitored and analyzed;
2. the isolated threshold is not used as a monitoring basis for the data processing unit to send out an alarm signal, and the threshold shielding function of the system is realized, so that the shutdown caused by false alarm is effectively avoided;
3. when the exceeding limit value appears in at least five continuous crankshaft rotation periods, the data processing unit can send out an alarm signal, so that the accuracy of the monitoring result can be improved, and unnecessary halt can be avoided;
4. and trend analysis is carried out on the sinking displacement values of different crankshaft rotation periods, so that the sinking displacement value of the piston rod can be predicted, and the abrasion trend of a piston supporting ring and a piston ring can be predicted.
Drawings
Fig. 1 is a schematic structural diagram of a piston rod sedimentation detection system with a threshold shielding function in an embodiment;
FIG. 2 is a linear plot of sink displacement value versus crankshaft angle for an embodiment.
In the figure: 1. a crankshaft; 2. a piston rod; 3. a data acquisition unit; 4. a data processing unit; 5. a data server; 6. and an industrial personal computer.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.
Example (b):
a piston rod settlement monitoring system with a threshold shielding function refers to fig. 1 and 2 and comprises a piston rod position sensor, a data collector 3, a crankshaft position sensor, a data processing unit 4, a data server 5 and an industrial personal computer 6; the device comprises a piston rod position sensor, a data processing unit 4, a data acquisition unit 3, a crankshaft position sensor, a data processing unit 4 and a signal isolation grating, wherein the piston rod position sensor is used for continuously acquiring a sinking displacement value of a piston rod 2, the crankshaft position sensor is used for acquiring an angle of a crankshaft 1, the data processing unit 4 is respectively connected with the data acquisition unit 3 and the crankshaft position sensor, and the signal isolation grating is arranged between the crankshaft position sensor and the data processing unit 4; in the embodiment, according to an angle signal sent by a crankshaft position sensor, a data acquisition unit 3 sends an acquisition instruction to a piston rod position sensor, and continuously measures the sinking displacement value of a piston rod 2 in a 360-degree rotation period of a crankshaft 1, so that the sinking displacement value of the piston rod 2 corresponds to the angle of the crankshaft 1; the sinking displacement value of the piston rod 2 corresponds to the angle of the crankshaft 1 in the embodiment, and the sinking displacement value can be periodically and accurately measured, monitored and analyzed, so that the threshold shielding function is conveniently realized, and unnecessary shutdown is avoided.
Referring to fig. 1 and 2, in particular, a limit value of the sinking displacement value of the piston rod 2 is set in the data processing unit 4, the received sinking displacement value is compared with the limit value according to the data processing unit 4, and the sinking displacement value reaching or exceeding the limit value is defined as an over-limit value; the over-limit value is used as a monitoring basis for the data processing unit 4 to send out an alarm signal; an isolated over-limit value that does not correspond to the trend of change of the sag displacement value, which occurs during the crankshaft rotation period, is defined as an isolated threshold value, such as the isolated threshold value that occurs around 120 ° in fig. 2; in this embodiment, the isolated threshold is not used as a monitoring basis for the data processing unit 4 to send out an alarm signal, so as to implement a threshold shielding function of the system, thereby effectively avoiding shutdown caused by false alarm.
With reference to fig. 1 and 2, the data processing unit 4 preferably only emits an alarm signal when an overrun occurs in at least two consecutive crankshaft rotation cycles; more preferably, the data processing unit 4 will only send an alarm signal when the over-limit value occurs for at least five consecutive crankshaft rotation periods; specifically, in this embodiment, the data processing unit 4 will send out an alarm signal only when the exceeding limit value occurs in five consecutive crankshaft rotation periods; the time of one crankshaft rotation period is very short, so that after the overrun value is monitored in the first crankshaft rotation period, four crankshaft rotation periods are continuously monitored, delay is not caused, the accuracy of the monitoring result can be improved, and unnecessary halt is avoided.
Referring to fig. 1 and 2, in the present embodiment, the sinking displacement value of the piston rod 2 is continuously measured within a 360 ° rotation period of the crankshaft 1, so that the sinking displacement value of the piston rod 2 corresponds to the angle of the crankshaft 1, and then the decision basis for sending the alarm signal has more choices, and can be matched with different types of compressors and more working conditions; for example, the data processing unit 4 compares the received sinking displacement value with the sinking displacement value of the previous crankshaft rotation cycle, and sends out an early warning signal or an alarm signal according to the comparison result; when the early warning signal is sent out, the compressor can still continue to work, and when the early warning signal is sent out, the compressor needs to stop working; wherein, the comparison result comprises the difference value of the sinking displacement values or the change rate of the difference value of the sinking displacement values;
referring to fig. 1 and 2, in this embodiment, a data analysis module (i.e., data analysis software) is disposed in the industrial control machine 6, and the data analysis module is configured to display a sinking displacement value of the piston rod 2 in real time and perform trend analysis on the sinking displacement values of different crankshaft rotation periods, so that the sinking displacement value of the piston rod 2 can be predicted, and further, a prejudgment can be made on wear trends of a piston support ring and a piston ring.
Referring to fig. 1 and 2, preferably, the piston rod position sensor in the present embodiment includes an upper piston rod position sensor and a lower piston rod position sensor, which are oppositely disposed at the upper side and the lower side of the piston rod 2, respectively; the sinking displacement value acquired by the upper piston rod position sensor is compared with the sinking displacement value acquired by the lower piston rod position sensor, and the coincidence value is taken as a monitoring basis, so that the accuracy can be improved; specifically, the displacement value that sinks that upside piston rod position sensor gathered is positive, and the displacement value that sinks that downside piston rod position sensor gathered is negative, after getting the negative of the displacement value that sinks that downside piston rod position sensor gathered, compares with the displacement value that sinks that upside piston rod position sensor gathered, gets the higher numerical value of complete coincidence or coincidence degree as the higher numerical value of credibility, as the monitoring foundation to can improve the precision.
Referring to fig. 1 and 2, in the present embodiment, the data acquisition device 3 is connected to a plurality of piston rod position sensors; specifically, in this embodiment, the data acquisition unit 3 employs distributed data acquisition and bus communication, that is, the monitoring information of each piston rod position sensor is collected to the data acquisition unit 3, and then is sent to the data processing unit 4 in a bus (CAN bus or 485 bus) manner, so that field wiring and connection CAN be reduced, and the installation cost CAN be saved.
Claims (10)
1. A piston rod subsidence monitoring system with threshold shield functionality comprising:
the piston rod position sensor is used for continuously acquiring a sinking displacement value of the piston rod;
the data acquisition unit is connected with the piston rod position sensor;
the crankshaft position sensor is used for acquiring the angle of a crankshaft;
the data processing unit is respectively connected with the data acquisition unit and the crankshaft position sensor;
the data server is connected with the data processing unit; and (c) a second step of,
the industrial personal computer is connected with the data server;
the method is characterized in that:
according to the angle signal sent by the crankshaft position sensor, the data acquisition unit sends an acquisition instruction to the piston rod position sensor, and continuously measures the sinking displacement value of the piston rod in a 360-degree rotation period of the crankshaft, so that the sinking displacement value of the piston rod corresponds to the angle of the crankshaft.
2. The piston rod subsidence monitoring system with threshold shielding function of claim 1, wherein: the data processing unit is internally provided with a limit value of the sinking displacement value of the piston rod, the data processing unit compares the received sinking displacement value with the limit value, and the sinking displacement value reaching or exceeding the limit value is defined as an over-limit value; the over-limit value is used as a monitoring basis for the data processing unit to send out an alarm signal;
defining an isolated over-limit value which does not accord with the variation trend of the sinking displacement value and appears in the rotation period of the crankshaft as an isolated threshold value; the isolated threshold value is not used as a monitoring basis for the data processing unit to send out an alarm signal.
3. The piston rod subsidence monitoring system with threshold shielding function of claim 1, wherein: the data processing unit is internally provided with a limit value of the sinking displacement value of the piston rod, the data processing unit compares the received sinking displacement value with the limit value, and the sinking displacement value reaching or exceeding the limit value is defined as an over-limit value;
when the exceeding limit value occurs in at least two continuous crankshaft rotation periods, the data processing unit sends out an alarm signal.
4. The piston rod subsidence monitoring system with threshold shielding function of claim 3, wherein: when the exceeding limit value appears in at least five continuous crankshaft rotation periods, the data processing unit sends out an alarm signal.
5. The piston rod subsidence monitoring system with threshold shielding function of claim 1, wherein: the data processing unit compares the received sinking displacement value with the sinking displacement value of the previous crankshaft rotation period and sends out an early warning signal or an alarm signal according to the comparison result;
when the early warning signal is sent out, the compressor can still continue to work, and when the early warning signal is sent out, the compressor needs to stop working.
6. The piston rod subsidence monitoring system with threshold shielding function of claim 5, wherein: the comparison result comprises a difference value of the sinking displacement values or a difference value change rate of the sinking displacement values.
7. The piston rod subsidence monitoring system with threshold shielding function of claim 1, wherein: the industrial personal computer is internally provided with a data analysis module which comprises a data analysis module used for carrying out trend analysis on the sinking displacement values of different crankshaft rotation periods.
8. The piston rod subsidence monitoring system with threshold shielding function of claim 1, wherein: the piston rod position sensor includes an upper piston rod position sensor and a lower piston rod position sensor, which are respectively oppositely disposed at an upper side and a lower side of the piston rod.
9. The piston rod subsidence monitoring system having a threshold shielding function of claim 8, wherein: and comparing the sinking displacement value acquired by the upper piston rod position sensor with the sinking displacement value acquired by the lower piston rod position sensor, and taking the coincidence value as a monitoring basis.
10. The piston rod subsidence monitoring system with threshold shielding function of claim 1, wherein: the data acquisition unit is connected with a plurality of piston rod position sensors.
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| CN202210417389.4A CN114674278B (en) | 2022-04-20 | 2022-04-20 | Piston rod settlement monitoring system with threshold shielding function |
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| CN202210417389.4A CN114674278B (en) | 2022-04-20 | 2022-04-20 | Piston rod settlement monitoring system with threshold shielding function |
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE29624456U1 (en) * | 1996-05-08 | 2003-12-18 | Kabushiki Kaisha Toyota Jidoshokki, Kariya | Reciprocating compressor - comprises cylinder blocks with cylinder bores, driving shaft supported on cylinder blocks, swash plate fixed to driving shaft, etc. |
| CN101126637A (en) * | 2006-08-16 | 2008-02-20 | 安德烈亚斯.斯蒂尔两合公司 | Method for determining the crankshaft position of a rotating crankshaft of an internal combustion engine |
| CN101813563A (en) * | 2009-12-15 | 2010-08-25 | 吉林大学 | Engine piston position and phase position full operation condition measurement system and method |
| US20160097694A1 (en) * | 2014-01-22 | 2016-04-07 | Deere & Company | Determining cylinder health in a reciprocating piston engine |
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| CN109780121A (en) * | 2019-02-13 | 2019-05-21 | 重庆大学 | Anti-settling MR damper based on on-line monitoring |
| CN111566330A (en) * | 2018-01-16 | 2020-08-21 | 法国大陆汽车公司 | Method for detecting a physical shutdown of an engine |
| CN113123952A (en) * | 2019-12-30 | 2021-07-16 | 无锡康茨压缩机配件与系统有限公司 | Load signal linearization processing method for stepless air volume adjustment of compressor |
-
2022
- 2022-04-20 CN CN202210417389.4A patent/CN114674278B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE29624456U1 (en) * | 1996-05-08 | 2003-12-18 | Kabushiki Kaisha Toyota Jidoshokki, Kariya | Reciprocating compressor - comprises cylinder blocks with cylinder bores, driving shaft supported on cylinder blocks, swash plate fixed to driving shaft, etc. |
| CN101126637A (en) * | 2006-08-16 | 2008-02-20 | 安德烈亚斯.斯蒂尔两合公司 | Method for determining the crankshaft position of a rotating crankshaft of an internal combustion engine |
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| US20160097694A1 (en) * | 2014-01-22 | 2016-04-07 | Deere & Company | Determining cylinder health in a reciprocating piston engine |
| CN107300375A (en) * | 2017-08-21 | 2017-10-27 | 四川西南交大铁路发展股份有限公司 | A kind of high-speed railway subgrade Monitoring method of the subsidence and system |
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| CN109780121A (en) * | 2019-02-13 | 2019-05-21 | 重庆大学 | Anti-settling MR damper based on on-line monitoring |
| CN113123952A (en) * | 2019-12-30 | 2021-07-16 | 无锡康茨压缩机配件与系统有限公司 | Load signal linearization processing method for stepless air volume adjustment of compressor |
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