CN202210015U - Airtightness detection device for CNG (compressed natural gas) fuel system - Google Patents
Airtightness detection device for CNG (compressed natural gas) fuel system Download PDFInfo
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- CN202210015U CN202210015U CN2011202731959U CN201120273195U CN202210015U CN 202210015 U CN202210015 U CN 202210015U CN 2011202731959 U CN2011202731959 U CN 2011202731959U CN 201120273195 U CN201120273195 U CN 201120273195U CN 202210015 U CN202210015 U CN 202210015U
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Abstract
The utility model discloses an efficient and low-cost airtightness detection device for a CNG (compressed natural gas) fuel system, which includes a booster pump, a booster pump driving device, a detection gas supply device, a detection gas output device and a CNG fuel system piezometric device, wherein the detection gas supply device and the detection gas output device are connected with a detection gas low-pressure air inlet end and a detection gas high-pressure outlet end of the booster pump through pipelines respectively; and the detection gas supply device is a CNG detection gas supply device, is a small-capacity low-pressure container of 45L to 300L in capacity and 2MPa to 19MPa in operating pressure to store the CNG detection gas, and is connected to the detection gas low-pressure air inlet end of the booster pump through a pipeline of the detection gas supply device. As no gas shifting is performed, the airtightness detection device for the CNG fuel system has high detection efficiency, excellent safety and low running cost, is light and handy, and convenient to move.
Description
Technical field
The application relates to air-tightness detection method and device, is specifically related to the bubble-tight detection method and the device of the CNG fuel system in the equipment such as vehicle.
Background technology
It is the main cause that causes vehicle blast, burning that the CNG gaseous fuel of CNG vehicle is revealed.Therefore, the strict impermeability that detects and control the CNG fuel system in the vehicle is the important means that prevents that this type of accident from taking place.Stipulated among the GB7258-2004 " motor vehicle safe operation technical conditions " that the CNG fuel system should satisfy the examination requirements that under the air pressure conditions of 20MPa, keeps no gas leakage in 5 minutes.
The detection method that can reach above-mentioned 20MPa air pressure conditions at present has only two kinds: a kind of is to be safe gas such as nitrogen or air with the CNG gas displacement in the CNG fuel system; And safe gas is pressurized to 20MPa, and then the air pressure change in the CNG fuel system is detected through supercharge pump; Another kind is to adopt the leak detection of compressed natural gas bottle group, makes it be pressurized to 20MPa in the CNG fuel system promptly directly that the input of the CNG gas in the compressed natural gas bottle group is to be checked, and then the air pressure change in the CNG fuel system is detected.
Above-mentioned first method needs through twice substitution gas process, sense cycle oversize (about 45 minutes) and have potential safety hazard.Though above-mentioned second method is without substitution gas, compressed natural gas bottle group is too huge, and floor area is wide; Safety and servicing unit require high, and pipe network is complicated, are equal to the pressurizing point of a CNG fueling station basically; Belong to fixed irremovable equipment, fire fighting device equipment etc. require high, and input ratio is bigger; The testing process security is very poor, and the consume of the gas during along with continuous detecting can not continue to provide specified detected pressures.
The utility model content
The application's technical matters to be solved provide a kind of efficiently, the air-tightness detection device of CNG fuel system cheaply.
This pick-up unit comprises supercharge pump, supercharge pump drive unit, detected gas feeder, detected gas output unit and CNG fuel system PMU; Said detected gas feeder is connected with detected gas high pressure outlet side with the detected gas low-pressure admission end of supercharge pump through pipeline respectively with the detected gas output unit; Wherein, The detected gas feeder is a CNG detected gas feeder, and this CNG detected gas feeder employing capacity is that 45L～300L and working pressure are that the low capacity low pressure vessel of 2MPa～19MPa is stored the CNG detected gas and is connected on the detected gas low-pressure admission end of supercharge pump through its pipeline.
Supercharge pump and supercharge pump drive unit can be respectively GPSQ gas boosting pump and driving gas feeder, and the driving gas feeder is connected on the driving gas inlet end of GPSQ gas boosting pump through its pipeline.Like this, can avoid air in supercharge pump, to mix with the CNG detected gas.
Concrete, said driving gas feeder comprises air compressor machine, air strainer, pressure adjusting pressuring valve, oil sprayer and the pressurized air stop valve that is serially connected by the pipeline order.
As further improvement to pick-up unit; Said CNG fuel system PMU is integrated on the detected gas output unit as the part of detected gas output unit, and the front end that is positioned at CNG fuel system PMU on the detected gas output unit is provided with CNG high pressure output detected gas stop valve.
The another step as to pick-up unit is improved the CNG pressurization gas outlet shutoff valve that the detected gas high pressure outlet side of supercharge pump and the pipeline between the detected gas output unit are provided with safe pressure relief device and are positioned at this safe pressure relief device rear end.
Concrete, said safe pressure relief device comprises the blowdown valve that is positioned at this safety blasting sheet rear end on the safety blasting sheet that is installed in the exhaust branch pipe, the exhaust branch pipe and at the CNG high pressure residual air interface and the CNG high pressure residual air exhausr port of this blowdown valve rear end branch.
As the concrete structure of CNG detected gas feeder, said CNG detected gas feeder comprises CNG gas bomb, CNG gas filling valve and the CNG source of the gas stop valve that is serially connected in proper order by its pipeline; CNG gas bomb employing capacity is that 45L～300L and working pressure are the low capacity gas bomb of 2MPa～19MPa.
The method of application of said apparatus may further comprise the steps:
A, the CNG detected gas input CNG fuel system that CNG detected gas feeder is provided through supercharge pump;
B, after the air pressure in the CNG fuel system reaches 20Mpa～23Mpa, stop gas transmission;
C, the air pressure change in the CNG fuel system is detected;
Wherein, CNG detected gas feeder employing capacity is that 45L～300L and working pressure are that the low capacity low pressure vessel of 2MPa～19MPa is stored the CNG detected gas.
The distinguishing feature of said method has been to use supercharge pump with lower (the direct input CNG fuel system after the CNG detected gas supercharging of 2MPa～19MPa) of air pressure in the CNG detected gas feeder; The testing conditions that finally makes the interior air pressure of CNG fuel system reach 20Mpa～23Mpa (can't reach the detection requirement if be lower than 20Mpa; If it is dangerous to be higher than 23Mpa); Therefore; This method need not be replaced the CNG gas that itself exists in the CNG fuel system, does not require that the CNG gas in the CNG detected gas feeder has higher pressure simultaneously again, so not only detection speed is fast for this method; And not making big volume high pressure vessel store the CNG gas in the CNG detected gas feeder again, operating cost is lower.
The usual supercharge pump that adopts in this area is a mechanical booster pump, but pays particular attention to mechanical booster pump issuable problem in this application the application's utility model people.Since all be in the past with safe gas such as nitrogen or air through supercharge pump input CNG fuel system and displacement CNG gas wherein, even if therefore in supercharge pump these safe gas mix with air, can not produce danger yet.But what the application used is the CNG detected gas, if the CNG detected gas is mixed in supercharge pump with air, will bring dangerous hidden danger.For this reason, the application's ad hoc proposal is in above-mentioned steps a, and passing through independently respectively, pipeline makes the CNG detected gas after the supercharging of GPSQ gas boosting pump, import the CNG fuel system again to GPSQ gas boosting pump input driving gas and CNG detected gas.
GPSQ gas boosting pump itself is a prior art, and its known characteristics are to accomplish twice pressurization in the period of motion in the once reciprocating of its driven plunger, thereby makes whole pressurization stable gently.And the main effect played of GPSQ gas boosting pump in this application is not in order to guarantee the mild stable of pressurization.The application's utility model people notices, because the gas compression cylinder at driving cylinder in the GPSQ gas boosting pump and two ends is independently of one another, so can be good at avoiding mixing of driving gas and CNG detected gas, stops potential potential safety hazard basically.
On the basis of said method, the application also advises on the pipeline between supercharge pump and the CNG fuel system, establishing safe pressure relief device, when the air pressure in the pipeline reaches the threshold values of setting, carries out pressure release through this safe pressure relief device.If safe pressure relief device can be avoided in the process of CNG fuel system gas transmission, the air pressure in the CNG fuel system surpasses the threshold values (like 28MPa) of this setting, avoids the damage because of the too high CNG of the causing fuel system of air pressure.
The beneficial effect of technique scheme mainly contains:
1, because substitution gas not, so detection efficiency is high, and has good security;
2, equipment light and handy, be convenient to move, operating cost is low;
3, can avoid CNG detected gas and air mixed behind the use GPSQ gas boosting pump, eliminate safe hidden trouble.
Description of drawings
Fig. 1 is the structural representation of the application's pick-up unit.
Fig. 2 is the application's pick-up unit power air inlet status of processes figure.
Fig. 3 detects with natural gas boosting status of processes figure for the application's pick-up unit.
Thick arrow among Fig. 2, Fig. 3 is represented the gas motion direction.
Dotted line among Fig. 1, Fig. 2 and Fig. 3 is represented the pipeline of driving gas and CNG detected gas.
Embodiment
At first combine accompanying drawing that the air-tightness detection device of the CNG fuel system of the utility model is done detailed explanation below, and then specify the air-tightness detection method of the CNG fuel system of the utility model through introduction to this device method of application.
The air-tightness detection device of CNG fuel system as shown in Figure 1; This device comprises GPSQ gas boosting pump 3, driving gas feeder 1, CNG detected gas feeder 2 and detected gas output unit 4; Wherein, Driving gas feeder 1 is connected on the driving gas inlet end of GPSQ gas boosting pump 3 through its pipeline 1e; CNG detected gas feeder 2 is connected on the detected gas low-pressure admission end of GPSQ gas boosting pump 3 through its pipeline 2c; 4 of detected gas output units are connected through pipeline on the detected gas high pressure outlet side of GPSQ gas boosting pump 3, and in the use of this device, the gas transmission joint of detected gas output unit 4 is connected with the gas port that adds of CNG fuel system 5.
Said structure has only constituted the CNG detected gas supercharging part of air-tightness detection device; Promptly assign to realize with the CNG detected gas supercharging in the CNG detected gas feeder 2 and import CNG fuel system 5, finally make to reach impermeability in the CNG fuel system 5 and detect needed pressure condition through this plenum.To finally understand CNG fuel system 5 and whether have leakage; Certainly also need reach impermeability and detect that the variation of pressure detects behind the needed pressure condition CNG fuel system 5; If promptly the air pressure in the CNG fuel system 5 reduces in certain sense cycle, then there is leakage in explanation.Therefore, constitute the complete air-tightness detection device of a cover, also need CNG fuel system PMU.CNG fuel system PMU both can be used as an independent annex, also can be partly to integrate with the supercharging of above-mentioned CNG detected gas.
Therefore; In this embodiment; CNG fuel system PMU is integrated on the detected gas output unit 4 as the part of detected gas output unit 4; And the front end that is positioned at CNG fuel system PMU on the detected gas output unit 4 is provided with CNG high pressure output detected gas stop valve 4a.Concretely, as shown in Figure 1, in fact CNG fuel system PMU is exactly the pressure transducer 4d that is connected on the pipeline 4c of detected gas output unit 4, and the indicating value of this pressure transducer 4d can be reflected on the digital readout system so that the operator observes.After CNG fuel system 5 inflated; Above-mentioned CNG high pressure output detected gas stop valve 4a is closed; At this moment CNG fuel system 5 constitutes a closed system that is isolated from the outside with detected gas output unit 4, can guarantee that pressure transducer 4d can detect this pressure that goes out closed system accurately and change.In addition, between pressure transducer 4d and CNG high pressure output detected gas stop valve 4a, can establish blowdown valve 4b, guarantee the gas transmission security.
As shown in Figure 1, the CNG detected gas feeder 2 in the air-tightness detection device of CNG fuel system comprises CNG gas bomb 2a, CNG gas filling valve 2d and the CNG source of the gas stop valve 2e that is serially connected in proper order by its pipeline 2c; CNG gas bomb 2a employing capacity is that 45L～300L and working pressure are the low capacity gas bomb of 2MPa～19MPa.As preferably, can the employing capacity be the low capacity gas bomb of 45L～55L.The volume size of the air-tightness detection device of CNG fuel system is mainly determined by the volume size of CNG gas bomb 2a; Because to have adopted capacity be 45L～300L, be preferably the low capacity gas bomb of 45L～55L; Therefore the volume of the air-tightness detection device of this CNG fuel system reduces than compressed natural gas bottle group greatly, the advantage that the equipment that reaches is light and handy, be convenient to move, operating cost is low.CNG gas bomb 2a is provided with bottleneck valve 2b.
As shown in Figure 1, the driving gas feeder 1 in the air-tightness detection device of CNG fuel system comprises air compressor machine 1a, air strainer 1b, pressure adjusting pressuring valve 1c, oil sprayer 1d and the pressurized air stop valve 1f that is serially connected in proper order by pipeline 1e.This driving gas feeder 1 can guarantee to import the pure air of 0.5Mpa～1.0Mpa, reaches the request for utilization of GPSQ gas boosting pump 3, guarantees the serviceable life of GPSQ gas boosting pump 3.
CNG pressurization gas outlet shutoff valve 3t as shown in Figure 1, that the detected gas high pressure outlet side of supercharge pump and the pipeline 3n between the detected gas output unit 4 are provided with safe pressure relief device and are positioned at this safe pressure relief device rear end.When the air pressure in the pipeline reaches the threshold values of setting, carry out pressure release through this safe pressure relief device.Concrete, said safe pressure relief device comprises and is positioned at the blowdown valve 3q of this safety blasting sheet 3p rear end on the safety blasting sheet 3p that is installed in the exhaust branch pipe, the exhaust branch pipe and the CNG high pressure residual air interface 3r and the CNG high pressure residual air exhausr port 3s of branch in this blowdown valve 3q rear end.Exhaust rapidly after the purpose of establishing blowdown valve 3q in safety blasting sheet 3p rear end is to prevent safety blasting sheet 3p explosion is avoided the CNG detected gas too much to reveal contaminated environment and is caused security incident.The CNG high pressure residual air interface 3r of branch and CNG high pressure residual air exhausr port 3s can import certain subsequent equipment or directly discharging with residual air respectively behind the blowdown valve 3q, are convenient to according to specifically needing the purpose operation.
GPSQ gas boosting pump 3 is an existing weaponry and equipment in the air-tightness detection device of CNG fuel system; As shown in Figure 1; Its concrete structure mainly comprises: Pneumatic reversal valve 3a (two-position four-way valve), control gas circuit 3b, pilot valve 3c, driven plunger 3d, piston rod 3e, two plunger 3f, two gas compression cylinder 3g, drive cylinder 3h, one-level gas compression cylinder inlet retaining valve 3i, one-level gas compression cylinder gas outlet retaining valve 3j, secondary gas compression cylinder inlet retaining valve 3k, secondary gas compression cylinder gas outlet retaining valve 3l; Wherein, One-level gas compression cylinder inlet retaining valve 3i is connected with CNG detected gas feeder 2; One-level gas compression cylinder gas outlet retaining valve 3j is connected with secondary gas compression cylinder inlet retaining valve 3k; Secondary gas compression cylinder gas outlet retaining valve 3l is connected with detected gas output unit 4, and Pneumatic reversal valve 3a is connected with driving gas feeder 1.
Below in conjunction with the method for application explanation of the air-tightness detection device of 2,3 pairs of CNG fuel system of accompanying drawing as follows:
At first, under CNG source of the gas stop valve 2e closed condition, open the bottleneck valve 2b of CNG gas bomb 2a, when the bottleneck tensimeter is shown as 2MPa～19Mpa, open CNG source of the gas stop valve 2e; Simultaneously, under pressurized air stop valve 1f closed condition, start air compressor machine 1a, regulate pressure adjusting pressuring valve 1c and make drive air tensimeter pressure, open pressurized air stop valve 1f then to 0.5Mpa～1.0Mpa;
As shown in Figure 2; After pressurized air gets into the driving cylinder 3h of GPSQ gas boosting pump 3 through Pneumatic reversal valve 3a; GPSQ gas boosting pump 3 just begins automatic work; At this moment; Pressurized air applies a pressure to the right to driven plunger 3d, and driven plunger 3d carries out compressing the first time and making it be pressurized to 3Mpa～6Mpa to the CNG detected gas in the gas compression cylinder 3g through the small size plunger 3f that is rigidly attached to its right-hand member in the process that moves right, and the CNG detected gas that this part is pressurized gets into the gas compression cylinder 3g of left end through one-level gas compression cylinder gas outlet retaining valve 3j, secondary gas compression cylinder inlet retaining valve 3k and the pipeline 3m between them;
As shown in Figure 3; When driven plunger 3d moves to driving cylinder 3h left end; Pilot valve 3c is triggered and switches through control gas circuit 3b control Pneumatic reversal valve 3a; At this moment; Compressed-air actuated airintake direction changes; Pressurized air applies a pressure left to driven plunger 3d, and driven plunger 3d is carrying out compressing the second time and making it be pressurized to 20Mpa～23Mpa to the CNG detected gas in the gas compression cylinder 3g through the small size plunger 3f that is rigidly attached to its left end in the process of left movement, retaining valve 31 output and through tensimeter 3o, safety blasting sheet 3p, CNG pressurization gas outlet shutoff valve 3t and detected gas output unit 4 back input CNG fuel system 5 from one-level gas compression cylinder gas outlet of the CNG detected gas after the supercharging; Simultaneously, the CNG detected gas in the CNG gas bomb 2a gets into the gas compression cylinder 3g on right side once more from one-level gas compression cylinder inlet retaining valve 3i;
After driven plunger 3d moved back and forth, the air pressure in the CNG fuel system 5 reached 20Mpa～23Mpa, stops gas transmission then; And close the CNG high pressure and export detected gas stop valve 4a; Under above-mentioned pressure, kept 5 minutes,, surpass 0.01Mpa therebetween if the indicating value of pressure transducer 4d descends; Characterize the CNG fuel system and have leakage, otherwise then do not have leakage.
Claims (7)
1.CNG the air-tightness detection device of fuel system; Comprise supercharge pump, supercharge pump drive unit, detected gas feeder, detected gas output unit (4) and CNG fuel system PMU; Said detected gas feeder is connected with detected gas high pressure outlet side with the detected gas low-pressure admission end of supercharge pump through pipeline respectively with detected gas output unit (4); It is characterized in that: the detected gas feeder is a CNG detected gas feeder (2), and this CNG detected gas feeder (2) employing capacity is that 45L～300L and working pressure are that the low capacity low pressure vessel of 2MPa～19MPa is stored the CNG detected gas and is connected on the detected gas low-pressure admission end of supercharge pump through its pipeline (2c).
2. the air-tightness detection device of CNG fuel system as claimed in claim 1; It is characterized in that: supercharge pump and supercharge pump drive unit are respectively GPSQ gas boosting pump (3) and driving gas feeder (1), and driving gas feeder (1) is connected on the driving gas inlet end of GPSQ gas boosting pump (3) through its pipeline (1e).
3. the air-tightness detection device of CNG fuel system as claimed in claim 2 is characterized in that: said driving gas feeder (1) comprises air compressor machine (1a), air strainer (1b), pressure adjusting pressuring valve (1c), oil sprayer (1d) and the pressurized air stop valve (1f) that is serially connected by pipeline (1e) order.
4. the air-tightness detection device of CNG fuel system as claimed in claim 1; It is characterized in that: said CNG fuel system PMU is integrated on the detected gas output unit (4) as the part of detected gas output unit (4), and the front end that is positioned at CNG fuel system PMU on the detected gas output unit (4) is provided with CNG high pressure output detected gas stop valve (4a).
5. like the air-tightness detection device of claim 1,2,3 or 4 described CNG fuel system, it is characterized in that: the CNG pressurization gas outlet shutoff valve (3t) that the pipeline (3n) between the detected gas high pressure outlet side of supercharge pump and the detected gas output unit (4) is provided with safe pressure relief device and is positioned at this safe pressure relief device rear end.
6. the air-tightness detection device of CNG fuel system as claimed in claim 5 is characterized in that: said safe pressure relief device comprises and is positioned at the blowdown valve (3q) of this safety blasting sheet (3p) rear end on the safety blasting sheet (3p) that is installed in the exhaust branch pipe, the exhaust branch pipe and the CNG high pressure residual air interface (3r) and the CNG high pressure residual air exhausr port (3s) of branch in this blowdown valve (3q) rear end.
7. like the air-tightness detection device of claim 1,2,3 or 4 described CNG fuel system, it is characterized in that: said CNG detected gas feeder (2) comprises CNG gas bomb (2a), CNG gas filling valve (2d) and the CNG source of the gas stop valve (2e) that is serially connected by its pipeline (2c) order; CNG gas bomb (2a) employing capacity is that 45L～300L and working pressure are the low capacity gas bomb of 2MPa～19MPa.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011202731959U CN202210015U (en) | 2011-07-29 | 2011-07-29 | Airtightness detection device for CNG (compressed natural gas) fuel system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011202731959U CN202210015U (en) | 2011-07-29 | 2011-07-29 | Airtightness detection device for CNG (compressed natural gas) fuel system |
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| Publication Number | Publication Date |
|---|---|
| CN202210015U true CN202210015U (en) | 2012-05-02 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2011202731959U Withdrawn - After Issue CN202210015U (en) | 2011-07-29 | 2011-07-29 | Airtightness detection device for CNG (compressed natural gas) fuel system |
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| CN (1) | CN202210015U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102410911A (en) * | 2011-07-29 | 2012-04-11 | 四川省特种设备检验研究院 | Detection method of gas tightness of CNG fuel system and detection apparatus thereof |
| CN114294563A (en) * | 2021-12-29 | 2022-04-08 | 广东逸动科技有限公司 | Gas pressurization system and control method thereof |
-
2011
- 2011-07-29 CN CN2011202731959U patent/CN202210015U/en not_active Withdrawn - After Issue
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102410911A (en) * | 2011-07-29 | 2012-04-11 | 四川省特种设备检验研究院 | Detection method of gas tightness of CNG fuel system and detection apparatus thereof |
| CN102410911B (en) * | 2011-07-29 | 2014-04-09 | 四川省特种设备检验研究院 | Detection method of gas tightness of CNG fuel system and detection apparatus thereof |
| CN114294563A (en) * | 2021-12-29 | 2022-04-08 | 广东逸动科技有限公司 | Gas pressurization system and control method thereof |
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| C14 | Grant of patent or utility model | ||
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| AV01 | Patent right actively abandoned |
Granted publication date: 20120502 Effective date of abandoning: 20140409 |
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| RGAV | Abandon patent right to avoid regrant |