CN213902769U

CN213902769U - Large-cavity multi-seal-structure container air tightness detection device

Info

Publication number: CN213902769U
Application number: CN202023011570.0U
Authority: CN
Inventors: 不公告发明人
Original assignee: 63653 Troops of PLA
Current assignee: 63653 Troops of PLA
Priority date: 2020-12-15
Filing date: 2020-12-15
Publication date: 2021-08-06
Anticipated expiration: 2030-12-15

Abstract

The utility model belongs to explosion container, many seal structure container gas tightness detection device of big cavity such as spacecraft, especially a many seal structure container gas tightness detection device of big cavity, including many seal structure containers of big cavity, setting up first through-hole in many seal structure container one side of big cavity, first through-hole is connecting gradually the vacuometer that has the standard small opening through the connecting tube, first valve and lobe pump, connecting the rotor plate pump through the second valve on the pipeline of the second through-hole connection of this side device, setting up the third through-hole at the opposite side of many seal structure containers of big cavity, connecting the leak detector through the molecular pump on the pipeline of third through-hole connection and installing the helium cover respectively in the each sealing position outside that distributes on many seal structure containers of big cavity. The utility model discloses it is rational in infrastructure, can improve leak hunting sensitivity to leaking the link pinpoint, local helium cover accurate positioning effectively shortens the reaction time of leak hunting system, shortens the air-bleed time of system, improves leak hunting efficiency.

Description

Large-cavity multi-seal-structure container air tightness detection device

Technical Field

The utility model belongs to many seal structure of big cavity container gas tightness detection device such as explosion vessel, spacecraft, especially a many seal structure of big cavity container gas tightness detection device.

Background

Common methods for vacuum leak detection include a blowing method and a helium hood method, wherein the helium hood method can collect a helium source to measure the overall leak rate or the local leak rate of a detected part and accurately position the leak rate. The method is very effective for the detected piece with small size and simple structure of the leakage detection part. When the size of the part to be detected is large, the leakage detection system has the problems of low leakage detection sensitivity, long reaction time and the like, and further the multi-seal structure cannot be accurately positioned.

The leak detection sensitivity of the large-cavity container is low, and the reaction time of a leak detection system is long. Particularly, under the condition that the sealing structure of the detected part is complex and has a plurality of sealing links, the accurate judgment of the position of the leakage link is one of the technical problems of leakage detection of the large-cavity detected part, the key parameter influencing the positioning of the leakage link is the reaction time, and the shorter the system reaction time is, the more the accurate positioning of the leakage hole is facilitated.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a many seal structure of big cavity container gas tightness detection device, its is rational in infrastructure, can improve leak hunting sensitivity to leaking the link pinpoint, and local helium cover accurate positioning effectively shortens leak hunting system's reaction time, shortens systematic bleed time, improves leak hunting efficiency.

The purpose of the utility model is realized like this: the utility model provides a many seal structure of big cavity container gas tightness detection device, including many seal structure of big cavity container, set up first through-hole in many seal structure of big cavity container one side, first through-hole is connecting the vacuometer that has the standard small opening in proper order through the connecting line, first valve and lobe pump, connect the rotor plate pump through the second valve on the pipeline that the second through-hole of this side device is connected, the third through-hole is being set up to the opposite side at many seal structure of big cavity container, connect the leak detector through the molecular pump on the pipeline of third through-hole connection, the helium cover is being installed respectively in each sealed position outside that distributes on many seal structure of big cavity container.

The reaction time of the leak detection system is determined by the leak detection system, and in order to shorten the reaction time of the system and improve the leak hole positioning capability, the leak detection system with high leak detection sensitivity and short system reaction time is designed.

The utility model discloses according to the reaction time of system, at leak hunting position installation helium cover, confirm according to the reaction of system and wait to examine the time, just can accurately judge the position of small opening. Finally, the efficiency is improved by reasonably using the pump sets of different types and correctly switching the opening and closing orders of the different pump sets, and the leak detection time is shortened.

The utility model is suitable for an explosion container, big cavity volume such as spacecraft (& gt 100L) or the gas yield is great like plastics, and grease etc. are examined the leakproofness of position and are detected, and leak hunting sensitivity is superior to 10^-8Pa·m³And/s, the leakage link can be accurately positioned. The vacuum pump is connected in series with the front end of the leak detector, and all gas pumped by the vacuum pump enters the leak detector, so that the problems that the leak detection sensitivity of a system is not influenced by a high-pumping-speed vacuum pump any more and the reaction time of the system is only shortened are solved; an independent helium cover is arranged at each sealing part, so that the leakage link can be accurately positioned; the relationship between the pumping speed and the vacuum degree of various vacuum pumps is correctly mastered, so that the pumping time of the system can be shortened, and the leak detection efficiency is improved.

The utility model discloses the technological effect who produces:

1 improvements in vacuum pumping systems

The method comprises the steps of detecting the sensitivity of a leakage detecting system and the response time of the leakage detecting system by two key parameters in the leakage detecting system, wherein the sensitivity of the leakage detecting system is related to the partial pressure P in the leakage detecting system, and the system response time tau is related to the volume V of the leakage detecting system and the effective pumping speed S of the leakage detecting system. The helium partial pressure in the original leakage detecting system is P, the system reaction time is tau, the helium partial pressure of the existing leakage detecting system is P ', the system reaction time is tau ', Q ' is the leakage rate of the detected part, S₁For pumping speed, S, of leak detectors₂For assisting the pumping speed of the pump_、S₁' is the pumping speed, S, of the molecular pump₂' is the pumping speed of the leak detector.

The helium partial pressure of the original leak detection system is related to the pumping speed of the leak detector and the auxiliary pump, and a part of helium gas is pumped away by the auxiliary pump. The utility model discloses a helium partial pressure is only relevant at the extraction rate of leak detector, and the helium is whole to get into the leak detector, does not have the influence to leak hunting sensitivity. So the utility model discloses a sensitivity is higher than former system. The system response time of former system and the pump-out rate of auxiliary pump and the pump-out rate of leak detector, the utility model discloses a response time only with can establish ties at the leak detector and the pump-out rate of the vacuum pump of examined the piece is relevant. Therefore, a vacuum pump with a large pumping speed can be selected, so that the system reaction time is shortened, and the problem that the original system cannot select an auxiliary pump with a large pumping speed (which influences the leak detection sensitivity) to shorten the system reaction time is solved.

2 local helium shroud accurate positioning

In the conventional leak detection method, the leak tightness of a local part is detected by using a helium cover method, but the leak detection method is difficult to realize for a large-volume detected piece, and once a leak point is found, the leak time is long, and accurate positioning is required. And the utility model discloses can realize accurate positioning in 5 minutes, prior art judges that the positioning time of small opening needs 55 minutes.

The utility model discloses a key technology point:

(1) the vacuum molecular pump is connected in series in the leak detection system, so that the flow dividing ratio is reduced, the leak detection sensitivity is improved, and the reaction time of the system is shortened.

(2) The local helium cover is accurately positioned, the reaction time of the leak detection system is effectively shortened, and the accurate positioning of the large-cavity multi-seal-link helium cover method is realized.

The utility model discloses a to leaking the link accurate positioning, improve leak hunting sensitivity, local helium cover accurate positioning effectively shortens the reaction time of leak hunting system, shortens the air-bleed time of system, improves leak hunting efficiency.

Drawings

It is right to refer to the accompanying drawings below the utility model discloses do further description, fig. 1 is the utility model discloses connection structure schematic diagram, fig. 2 is former leak hunting system principle schematic diagram, fig. 3 is the utility model discloses leak hunting system principle schematic diagram.

Detailed Description

A large-cavity multi-seal structure container airtightness detection device is shown in figures 1, 2 and 3 and comprises a large-cavity multi-seal structure container 11, wherein a first through hole is formed in one side of the large-cavity multi-seal structure container 11, the first through hole is sequentially connected with a vacuum gauge 4 with a standard leak hole 3, a first valve 5 and a roots pump 6 through a connecting pipeline, a rotary vane pump 7 is connected to a pipeline connected with a second through hole of the large-cavity multi-seal structure container 11 through a second valve 8, a third through hole is formed in the other side of the large-cavity multi-seal structure container 11, a leak detector 9 is connected to a pipeline connected with the third through hole through a molecular pump 10, and helium covers 1 are respectively installed on the outer sides of sealing parts 2 distributed on the large-cavity multi-seal structure container 11.

The volume of the large-cavity multi-seal structure container is more than 100L.

A detection method of a large-cavity multi-seal structure container air tightness detection device comprises the following steps of 1) firstly starting a rotary vane pump 7, vacuumizing a large-cavity multi-seal structure container 11 to be detected, and closing the rotary vane pump 7 when the vacuum degree reaches 8000 Pa;

2) starting the roots pump 6, continuously vacuumizing the large-cavity multi-seal-structure container 11 to be detected, and closing the roots pump 6 when the vacuum degree reaches 100 Pa;

3) starting the leak detector 9, and then starting the molecular pump 10 to enable all gas discharged by the molecular pump 10 to enter the leak detector 9;

4) after the background of the leak detector 9 is stable, opening the standard leak hole 3, calibrating the sensitivity of the detected system, and estimating the system reaction time;

5) then, corresponding to the position of the leak detector 9, helium covers 1 are respectively arranged on the outer sides of all sealing parts 2 distributed on the large-cavity multi-sealing structure container from top to bottom in sequence from near to far, helium is respectively added into each helium cover 1, the time for adding the helium is 3 times of the reaction time of the leak detection system, and the position of a leak hole can be accurately judged according to the change of the reaction time of the leak detection system.

The helium partial pressure of the leak detection system is

The reaction time of the leak detection system is

Where Q' is the sensitivity of the leak detection system, S₂'is the pumping speed after the pump of the leakage detection system, V is the volume of the system to be detected, and S' is the pumping speed before the pump.

The system response time is the time required from when the helium gas enters the leak until the output meter variation reaches 63% of its maximum value.

Claims

1. The utility model provides a many seal structure of big cavity container gas tightness detection device, includes many seal structure of big cavity container (11), characterized by: set up first through-hole in big many seal structure container of cavity (11) one side, first through-hole is connecting in proper order vacuum gauge (4) that have standard small opening (3), first valve (5) and lobe pump (6) through connecting line, connecting rotor pump (7) through second valve (8) on the pipeline of the second through-hole connection of this side device, the opposite side in big many seal structure container of cavity (11) is setting up the third through-hole, connect leak detector (9) through molecular pump (10) on the pipeline of third through-hole connection, helium cover (1) are being installed respectively in each seal part (2) outside that distributes on big many seal structure container of cavity (11).

2. The device for detecting the air tightness of the large-cavity multi-seal-structure container according to claim 1, wherein: the volume of the large-cavity multi-seal structure container is more than 100L.