CN103913279A - Method and device for testing leakproofness of oil cooler by mixing helium and air - Google Patents

Method and device for testing leakproofness of oil cooler by mixing helium and air Download PDF

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Publication number
CN103913279A
CN103913279A CN201410135483.6A CN201410135483A CN103913279A CN 103913279 A CN103913279 A CN 103913279A CN 201410135483 A CN201410135483 A CN 201410135483A CN 103913279 A CN103913279 A CN 103913279A
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CN
China
Prior art keywords
helium
vacuum tank
oil cooler
pipeline
solenoid valve
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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.)
Pending
Application number
CN201410135483.6A
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Chinese (zh)
Inventor
麦小波
陈吉洋
许永波
许光威
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Zhejiang Yinlun Machinery Co Ltd
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Zhejiang Yinlun Machinery Co Ltd
Priority date (The priority date 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 date listed.)
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Publication date
Application filed by Zhejiang Yinlun Machinery Co Ltd filed Critical Zhejiang Yinlun Machinery Co Ltd
Priority to CN201410135483.6A priority Critical patent/CN103913279A/en
Publication of CN103913279A publication Critical patent/CN103913279A/en
Pending legal-status Critical Current

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Abstract

The invention belongs to the technical field of seal test equipment, and particularly relates to a method and device for testing the leakproofness of an oil cooler by mixing helium and air. The device comprises a vacuum box and a gas mixing and temporary storing device which is connected with the oil cooler through a mixed gas conveying pipeline with an electromagnetic valve. The gas mixing and temporary storing device is connected with a helium gas source and a compressed air source through a pipeline with an electromagnetic valve. A helium gas concentration sensor is arranged on the gas mixing and temporary storing device. A flowmeter and a pressure sensor are arranged on a pipeline. The vacuum box is vacuumized by a vacuum pump. An oil cooler decompression pipeline is arranged on the mixed gas conveying pipeline. A helium gas leak detector and an electromagnetic valve are arranged on a pipeline between the vacuum pump and the vacuum box, and the vacuum box is connected with a vacuum box decompression pipeline used for decompressing the vacuum box. The method and device for testing the leakproofness of the oil cooler by mixing helium and air have the advantages of being low in equipment cost, low in using cost, high in production efficiency, high in degree of accuracy and high in reliability.

Description

Utilize the method and apparatus of helium and air hybrid test oil cooler sealing
Technical field
The invention belongs to leakage test equipment technical field, refer in particular to a kind of method and apparatus that utilizes helium and air hybrid test oil cooler sealing.
Background technology
Sealing is the key characteristic of oil cooler, and performing leak test is one of critical process of oil cooler production.The performing leak test of oil cooler can use pressurized air-water examination leak detection, the dry examination of pressurized air leak detection, helium leak check etc.Pressurized air-water examination leak detection is the pressurized air that is filled with certain pressure in oil cooler, and whole product is immersed in the water, and observes emerging of bubble and determines whether to leak, and shortcoming is manually likely to occur erroneous judgement, and follow-up needs dries.The dry examination leak detection of pressurized air is to be filled with pressurized air in oil cooler inside, then adopt the variation of sensor sensing pressure to judge whether product leaks, can realize automation mechanized operation, shortcoming is the reason of expanding with heat and contract with cold due to gas, pressure temperature influence is very large, the temperature environment that also easily appearance erroneous judgement or needs are good and for a long time steady pressure.Helium leak check instrument is the helium that oil cooler inside is filled with to certain pressure, and oil cooler is positioned in vacuum tank, judge by the helium gas molecules number change detecting in vacuum tank whether product leaks, shortcoming is that helium expense is very high, in the situation that having helium recovery system, the consumption of helium or too high, not only equipment cost is high, and use cost is also very high.
Summary of the invention
The object of this invention is to provide a kind of helium use amount of saving and reduce costs, detect the method and apparatus that utilizes helium and air hybrid test oil cooler sealing that effect accuracy is high.
The present invention is achieved in that
Utilize the equipment of helium and air hybrid test oil cooler sealing, include the vacuum tank for placing oil cooler, the gas being connected by mixed gas delivery pipeline with oil cooler mixes and temporary storage, gas mixes and temporary storage is connected with helium source of the gas by helium transfer pipeline, compressed air line is connected with compressed air gas source, on gas mixing and temporary storage, be provided with concentrations of helium sensor, on helium transfer pipeline, on compressed air conveying pipeline, be provided with flow and take into account pressure transducer, vacuum tank is vacuumized by vacuum pump, on described mixed gas delivery pipeline, on helium transfer pipeline, on compressed air conveying pipeline, be provided with solenoid valve, on mixed gas delivery pipeline, be provided with oil cooler pressure relief pipe, on the pipeline between vacuum pump and vacuum tank, be provided with helium leak check instrument, and on pipeline, be provided with the solenoid valve of controlling vacuum tank and helium leak check instrument UNICOM or shutoff, on vacuum tank, be connected with the vacuum tank pressure relief pipe that vacuum tank is carried out to pressure release, flowmeter, pressure transducer, helium leak check instrument and concentrations of helium sensor are connected with control system, described solenoid valve is by control system control action.
Above-mentioned oil cooler pressure relief pipe, vacuum tank pressure relief pipe are on pipeline, to be provided with solenoid valve, and solenoid valve is connected with control system.
Above-mentioned oil cooler pressure relief pipe is arranged on mixed gas delivery pipeline between oil cooler and solenoid valve.
On pipeline between above-mentioned vacuum pump and vacuum tank, being provided with helium leak check instrument is: the bye-pass that is provided with UNICOM's vacuum tank on the pipeline between vacuum pump and vacuum tank, on bye-pass, be provided with helium leak check instrument, the solenoid valve of controlling helium leak check instrument and vacuum tank UNICOM or shutoff is arranged on bye-pass.
On bye-pass between above-mentioned solenoid valve and vacuum tank, be provided with vacuum tank pressure relief pipe; Or be provided with vacuum tank pressure relief pipe on pipeline between vacuum pump and vacuum tank; Or on vacuum tank, be provided with vacuum tank pressure relief pipe.
The method of utilizing helium and air hybrid test oil cooler sealing, concrete steps are as follows:
(1) oil cooler is placed in vacuum tank by frock clamp, one end of the mixed gas delivery pipeline in vacuum tank is connected with oil cooler, and vacuum tank is built sealing;
(2) start vacuum pump, to in vacuum tank, vacuumize, solenoid valve on meanwhile controller control helium transfer pipeline and compressed air conveying pipeline, pressurized air in helium and compressed air gas source in helium source of the gas enters gas by helium transfer pipeline and compressed air conveying pipeline to be mixed and in reservoir, mixes temporarily, in inflation mixed process, control system obtains the aeration quantity of two kinds of gases of Data Control by pressure transducer, flowmeter and concentrations of helium sensor;
(3) when being evacuated down to the force value of setting in vacuum tank, open the solenoid valve on mixed gas delivery pipeline, in oil cooler, be filled with mixed gas, open the solenoid valve on the pipeline between helium leak check instrument and vacuum tank, helium leak check instrument starts to check helium molecule situation of change in vacuum tank:
At the appointed time, exceed setting value if helium gas molecules changes, control system judges that oil cooler leaks, and stops detecting and alarm logging; Otherwise it is qualified that control system is judged, stamps mark of conformity;
(4) detect completely, open solenoid valve on pressure relief pipe by pressure relief pipe pressure release, close other solenoid valve on other pipelines, unclamp frock clamp, take out oil cooler.
In above-mentioned step (2), helium accounts for 5~15%, and pressurized air accounts for 85~95%, mixture pressure 0.5~3MPa.
In above-mentioned step (2), vacuum tank is evacuated down to absolute pressure 1~500Pa.
The advantage that the present invention gives prominence to is compared to existing technology:
The present invention, compared with pure helium leak check method, has the advantages that cost of equipment is low, cost of use is low; Compared with the dry examination of pressurized air test method, have the advantages that production efficiency is high, accuracy is high, reliability is high.
Brief description of the drawings
Fig. 1 is helium of the present invention and the schematic diagram of air mixing sealing test method pipe system.
In figure, 1-vacuum tank, 2-oil cooler, 3-vacuum tank pressure relief pipe, 4-solenoid valve, 5-solenoid valve, 6-helium leak check instrument, 7-oil cooler pressure relief pipe, 8-solenoid valve, 9-flowmeter, 10-pressure transducer, 11-helium transfer pipeline, 12-solenoid valve, 13-compressed air conveying pipeline, 14-pressure transducer, 15-solenoid valve, 16-flowmeter, 17-gas mixes and interim reservoir, 18-concentrations of helium sensor, 19-vacuum pump, 20-mixed gas delivery pipeline, 21-solenoid valve, 22-bye-pass.
Embodiment
Below in conjunction with accompanying drawing, with specific embodiment, the invention will be further described, referring to Fig. 1:
The equipment that utilizes helium and air hybrid test oil cooler sealing, includes vacuum tank 1, oil cooler 2 is placed in vacuum tank 1, and oil cooler 2 mixes with gas by mixed gas delivery pipeline 20 and temporary storage 17 is connected, and gas mixes and temporary storage 17 is connected with helium source of the gas by helium transfer pipeline 11, compressed air line 13 is connected with compressed air gas source, is provided with concentrations of helium sensor 18, on helium transfer pipeline 11 on gas mixing and temporary storage 17, on compressed air conveying pipeline 13, be provided with flowmeter 9, 16 and pressure transducer 10, 14, vacuum tank 1 is vacuumized by vacuum pump 19, on described mixed gas delivery pipeline 20, on helium transfer pipeline 11, on compressed air conveying pipeline 13, be provided with solenoid valve 8, 12, 15, on mixed gas delivery pipeline 20, be provided with oil cooler pressure relief pipe 7, on the pipeline between vacuum pump 19 and vacuum tank 1, be provided with helium leak check instrument 6, and on pipeline, be provided with the solenoid valve 5 of controlling vacuum tank 1 and helium leak check instrument 6 UNICOMs or shutoff, on vacuum tank 1, be connected with the vacuum tank pressure relief pipe 3 that vacuum tank 1 is carried out to pressure release, flowmeter 9, 16, pressure transducer 10, 14, helium leak check instrument 6 and concentrations of helium sensor 10, 14 are connected with control system, described solenoid valve 5, 8, 12, 15 by control system control action.
Above-mentioned oil cooler pressure relief pipe 7, vacuum tank pressure relief pipe 3 is on pipeline, to be provided with solenoid valve 4,21, and solenoid valve 4,21 is connected with control system.
Above-mentioned oil cooler pressure relief pipe 7 is arranged on mixed gas delivery pipeline 20 between oil cooler 2 solenoid valves 8.
On pipeline between above-mentioned vacuum pump 19 and vacuum tank 1, being provided with helium leak check instrument 6 is: the bye-pass 22 that is provided with UNICOM's vacuum tank 1 on the pipeline between vacuum pump 19 and vacuum tank 1, on bye-pass 22, be provided with helium leak check instrument 6, control helium leak check instrument 6 and be arranged on bye-pass 22 with the solenoid valve 5 of vacuum tank 1 UNICOM or shutoff.
On bye-pass 22 between above-mentioned solenoid valve 5 and vacuum tank 1, be provided with vacuum tank pressure relief pipe 3; Or be provided with vacuum tank pressure relief pipe 3 on pipeline between vacuum pump 19 and vacuum tank 1; Or on vacuum tank 1, be provided with vacuum tank pressure relief pipe 3.
The method of utilizing helium and air hybrid test oil cooler sealing, concrete operation method is as follows:
Oil cooler 2 is placed in vacuum tank 1, fixes by frock clamp, with mixed gas delivery pipeline 20, oil cooler 2 and gas are mixed and interim reservoir 17 is connected, seals, vacuum tank is built sealing.Then press start button, vacuum pump 19 starts vacuum tank 1 to vacuumize, solenoid valve 12 and 15 is opened to gas and is mixed and temporary storage 17 inflation mixing simultaneously, in the process of mixing in inflation, the aeration quantity of two kinds of gases of Data Control that system obtains by pressure transducer 10,14, flowmeter 9,16 and concentrations of helium sensor 18, obtain concentrations of helium 5~15%(very few helium ratio and be unfavorable for detecting, too much helium ratio will improve expense), pressurized air concentration 85~95%, pressure 0.5~3MPa(sets according to product needed).Be evacuated down to the force value of setting, open solenoid valve 8 and be filled with mixed gas in oil cooler 2, open solenoid valve 5, helium leak check instrument 6 starts to check helium molecule situation of change in vacuum tank.At the appointed time, if helium gas molecules changing value exceedes setting value, illustrate that oil cooler 2 leaks, detect and finish, system alarm record; Otherwise, illustrate that product is qualified, stamp mark of conformity record.Detect completely, carry out pressure release by oil cooler pressure relief pipe 3, vacuum tank pressure relief pipe 7, close other solenoid valve 5,8,12,15 on other pipelines, unclamp frock clamp, take out product.
Above-described embodiment is only preferred embodiment of the present invention, not limits the scope of the invention according to this, therefore: all equivalences of doing according to structure of the present invention, shape, principle change, within all should being covered by protection scope of the present invention.

Claims (8)

1. utilize the equipment of helium and air hybrid test oil cooler sealing, it is characterized in that: include the vacuum tank for placing oil cooler, the gas being connected by mixed gas delivery pipeline with oil cooler mixes and temporary storage, gas mixes and temporary storage is connected with helium source of the gas by helium transfer pipeline, compressed air line is connected with compressed air gas source, on gas mixing and temporary storage, be provided with concentrations of helium sensor, on helium transfer pipeline, on compressed air conveying pipeline, be provided with flow and take into account pressure transducer, vacuum tank is vacuumized by vacuum pump, on described mixed gas delivery pipeline, on helium transfer pipeline, on compressed air conveying pipeline, be provided with solenoid valve, on mixed gas delivery pipeline, be provided with oil cooler pressure relief pipe, on the pipeline between vacuum pump and vacuum tank, be provided with helium leak check instrument, and on pipeline, be provided with the solenoid valve of controlling vacuum tank and helium leak check instrument UNICOM or shutoff, on vacuum tank, be connected with the vacuum tank pressure relief pipe that vacuum tank is carried out to pressure release, flowmeter, pressure transducer, helium leak check instrument and concentrations of helium sensor are connected with control system, described solenoid valve is by control system control action.
2. the equipment that utilizes helium and air hybrid test oil cooler sealing according to claim 1, is characterized in that: described oil cooler pressure relief pipe, vacuum tank pressure relief pipe are on pipeline, to be provided with solenoid valve, and solenoid valve is connected with control system.
3. the equipment that utilizes helium and air hybrid test oil cooler sealing according to claim 2, is characterized in that: described oil cooler pressure relief pipe is arranged on mixed gas delivery pipeline between oil cooler and solenoid valve.
4. the equipment that utilizes helium and air hybrid test oil cooler sealing according to claim 1, it is characterized in that: on the pipeline between described vacuum pump and vacuum tank, being provided with helium leak check instrument is: the bye-pass that is provided with UNICOM's vacuum tank on the pipeline between vacuum pump and vacuum tank, on bye-pass, be provided with helium leak check instrument, the solenoid valve of controlling helium leak check instrument and vacuum tank UNICOM or shutoff is arranged on bye-pass.
5. the equipment that utilizes helium and air hybrid test oil cooler sealing according to claim 4, is characterized in that: on the bye-pass between described solenoid valve and vacuum tank, be provided with vacuum tank pressure relief pipe; Or be provided with vacuum tank pressure relief pipe on pipeline between vacuum pump and vacuum tank; Or on vacuum tank, be provided with vacuum tank pressure relief pipe.
6. the equipment that utilizes helium and air hybrid test oil cooler sealing of utilization as described in claim 1-5 carries out the method for performing leak test to oil cooler, it is characterized in that: concrete steps are as follows:
(1) oil cooler is placed in vacuum tank by frock clamp, one end of the mixed gas delivery pipeline in vacuum tank is connected with oil cooler, and vacuum tank is built sealing;
(2) start vacuum pump, to in vacuum tank, vacuumize, solenoid valve on meanwhile controller control helium transfer pipeline and compressed air conveying pipeline, pressurized air in helium and compressed air gas source in helium source of the gas enters gas by helium transfer pipeline and compressed air conveying pipeline to be mixed and in reservoir, mixes temporarily, in inflation mixed process, control system obtains the aeration quantity of two kinds of gases of Data Control by pressure transducer, flowmeter and concentrations of helium sensor;
(3) when being evacuated down to the force value of setting in vacuum tank, open the solenoid valve on mixed gas delivery pipeline, in oil cooler, be filled with mixed gas, open the solenoid valve on the pipeline between helium leak check instrument and vacuum tank, helium leak check instrument starts to check helium molecule situation of change in vacuum tank:
At the appointed time, exceed setting value if helium gas molecules changes, control system judges that oil cooler leaks, and stops detecting and alarm logging; Otherwise it is qualified that control system is judged, stamps mark of conformity;
(4) detect completely, open solenoid valve on oil cooler pressure relief pipe and vacuum tank pressure relief pipe by pressure relief pipe pressure release, close other solenoid valve on other pipelines, unclamp frock clamp, take out oil cooler.
7. the method for utilizing helium and air hybrid test oil cooler sealing according to claim 6, is characterized in that: in described step (2), helium accounts for 5~15%, and pressurized air accounts for 85~95%, mixture pressure 0.5~3MPa.
8. the method for utilizing helium and air hybrid test oil cooler sealing according to claim 6, is characterized in that: in described step (2), vacuum tank is evacuated down to absolute pressure 1~500Pa.
CN201410135483.6A 2014-04-04 2014-04-04 Method and device for testing leakproofness of oil cooler by mixing helium and air Pending CN103913279A (en)

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CN201410135483.6A CN103913279A (en) 2014-04-04 2014-04-04 Method and device for testing leakproofness of oil cooler by mixing helium and air

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Application Number Priority Date Filing Date Title
CN201410135483.6A CN103913279A (en) 2014-04-04 2014-04-04 Method and device for testing leakproofness of oil cooler by mixing helium and air

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Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105546332A (en) * 2015-09-21 2016-05-04 王明华 Method and device for filling air balloon with gas mixture of helium gas and air
CN107449559A (en) * 2017-09-13 2017-12-08 苏州热工研究院有限公司 A kind of helium leakage inspection method for pond stainless steel clad can in nuclear power generating sets control zone
CN108507726A (en) * 2018-02-28 2018-09-07 重庆广福科技有限公司 The mechanism of detectable auto parts machinery air-tightness
CN109163858A (en) * 2018-09-04 2019-01-08 爱发科东方真空(成都)有限公司 A kind of sealing clamp and its method applied to vacuum helium leak test
CN110411676A (en) * 2019-07-15 2019-11-05 合肥通用机械研究院有限公司 A kind of valve leak amount detecting device
CN111006821A (en) * 2019-12-10 2020-04-14 西安欧中材料科技有限公司 Powder disc sheath built-in type leakage detection device and leakage detection method thereof

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CN201417199Y (en) * 2009-06-26 2010-03-03 博益(天津)气动技术研究所有限公司 Leak detection device for aircraft oil tank
CN103308254A (en) * 2013-05-06 2013-09-18 浙江银轮机械股份有限公司 Dry test method and dry test device for testing leak tightness of oil cooler
CN203287167U (en) * 2013-05-16 2013-11-13 浙江银轮机械股份有限公司 Dry test equipment for sealing performance of oil cooler
CN203798515U (en) * 2014-04-04 2014-08-27 浙江银轮机械股份有限公司 Equipment for testing sealing of oil cooler by using mixing of helium and air

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Publication number Priority date Publication date Assignee Title
JP2500488B2 (en) * 1991-02-08 1996-05-29 ヤマハ株式会社 Leak test method and leak test device
JP3203528B2 (en) * 1993-03-16 2001-08-27 株式会社生野製作所 Airtightness inspection method and device
CN201417199Y (en) * 2009-06-26 2010-03-03 博益(天津)气动技术研究所有限公司 Leak detection device for aircraft oil tank
CN103308254A (en) * 2013-05-06 2013-09-18 浙江银轮机械股份有限公司 Dry test method and dry test device for testing leak tightness of oil cooler
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Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105546332A (en) * 2015-09-21 2016-05-04 王明华 Method and device for filling air balloon with gas mixture of helium gas and air
CN107449559A (en) * 2017-09-13 2017-12-08 苏州热工研究院有限公司 A kind of helium leakage inspection method for pond stainless steel clad can in nuclear power generating sets control zone
CN107449559B (en) * 2017-09-13 2019-04-23 苏州热工研究院有限公司 A kind of helium leakage inspection method for pond stainless steel clad can in nuclear power unit control zone
CN108507726A (en) * 2018-02-28 2018-09-07 重庆广福科技有限公司 The mechanism of detectable auto parts machinery air-tightness
CN109163858A (en) * 2018-09-04 2019-01-08 爱发科东方真空(成都)有限公司 A kind of sealing clamp and its method applied to vacuum helium leak test
CN110411676A (en) * 2019-07-15 2019-11-05 合肥通用机械研究院有限公司 A kind of valve leak amount detecting device
CN111006821A (en) * 2019-12-10 2020-04-14 西安欧中材料科技有限公司 Powder disc sheath built-in type leakage detection device and leakage detection method thereof

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Application publication date: 20140709