A kind of helium mass spectrum leak detecting device of low pressure workpiece
The utility model relates generally to vacuum helium mass spectrum leak detection field, specifically a kind of helium mass spectrum leakage detection method of low pressure workpiece.
As you know in leak detection industry, particularly helium mass spectrum leak detection, has requirement to the vacuum tightness that examined workpiece reaches when it detects.During the vacuum leak hunting of helium mass spectrum, the vacuum tightness of workpiece at least should reach below 1500pa, otherwise is difficult to carry out valve opening detection.So first helium Mass Spectrometer Method is just start after the vacuum tightness in workpiece is evacuated to below 1500pa to detect under normal circumstances.But some workpiece can not reach higher vacuum tightness due to the restriction of the factor such as material, toughness, but needs again to detect its sealing.Helium Mass Spectrometer Method for this kind of workpiece just acquires a certain degree of difficulty, and method provided herein is exactly achieve helium mass spectrum leak detection in the pressure allowed band that can ensure workpiece.
utility model content:
The purpose of this utility model just provides a kind of helium mass spectrum leakage detection method of low pressure workpiece, realizes inside workpiece maintenance helium mass spectrum Leak Detection under a certain pressure.
The utility model is achieved through the following technical solutions:
A kind of helium mass spectrum leak detecting device of low pressure workpiece, it is characterized in that: include the vacuum pipe that the inner sealing that detects workpiece with low pressure is connected, the other end of vacuum pipe connects backing vacuum pump, vacuum pipe is provided with successively threeway, four-way, manual gear plate valve, pressure maintaining valve of finding time, described threeway, four-way are communicated with the inside of vacuum pipe, the other end of threeway is provided with vacuum meter, the another two ends of four-way are respectively equipped with Manual air-release valves, suction gun, the suction gun port of suction gun is embedded in the middle part of four-way, and suction gun is connected with helium mass spectrometer leak detector.
Principle of work of the present utility model is:
Backing vacuum pump is found time to workpiece, and vacuum meter detects the pressure of inside workpiece, and Manual air-release valves, pressure maintaining valve of finding time regulate inside workpiece pressure, make it in allowed limits; Suction gun port is fixed in vacuum pipe, and the suction gun other end is connected with helium mass spectrometer leak detector.At workpiece periphery spray helium, if there is leakage, then helium can be sucked in helium mass spectrometer leak detector by suction gun and be detected.In a word, examined workpiece can be met and allow within the scope of certain pressure, helium mass spectrum Leak Detection can be achieved again.
Advantage of the present utility model:
The utility model achieves the helium mass spectrum Leak Detection of low pressure workpiece, and workable, accuracy of detection is higher, and it is lower that system realizes cost.
accompanying drawing illustrates:
Fig. 1 is the structural representation of patent of the present invention.
As shown in Figure 1, a kind of helium mass spectrum leak detecting device of low pressure workpiece, include the vacuum pipe 8 that the inner sealing that detects workpiece 1 with low pressure is connected, the other end of vacuum pipe 8 connects backing vacuum pump 9, vacuum pipe 8 is provided with threeway 10 successively, four-way 11, manual gear plate valve 6, to find time pressure maintaining valve 7, described threeway 10, four-way 10 is communicated with the inside of vacuum pipe 8, the other end of threeway 10 is provided with vacuum meter 2, the another two ends of four-way 11 are respectively equipped with Manual air-release valves 3, suction gun 4, the suction gun port of suction gun 4 is embedded in the middle part of four-way 11, suction gun 4 is connected with helium mass spectrometer leak detector 5.
Manual gear plate valve 6 is used for opening, cutting out auxiliary gas circuit use of finding time.Pressure maintaining valve 7 of finding time is mainly used to regulate auxiliary flow of finding time, and regulates low pressure to detect workpiece 1 internal pressure.Auxiliary return pump 9 mainly finds time to use to workpiece, coordinates helium mass spectrometer leak detector 5 to work and uses.
During work, by finding time, pressure maintaining valve 7 regulates low pressure to detect the internal pressure of workpiece 1 with Manual air-release valves 3, it is made to keep constant under a certain pressure, pressure size can be carried out measurement by vacuum meter 2 and be obtained, workpiece 1 outside spray helium is detected like this in low pressure, if there is leakage, helium can be sucked by suction gun 4 and enter in helium mass spectrometer leak detector 5, realizes the helium Mass Spectrometer Method in workpiece pressure allowed band.