JP3046188B2 - Method and apparatus for testing airtight leakage of containers - Google Patents
Method and apparatus for testing airtight leakage of containersInfo
- Publication number
- JP3046188B2 JP3046188B2 JP5304502A JP30450293A JP3046188B2 JP 3046188 B2 JP3046188 B2 JP 3046188B2 JP 5304502 A JP5304502 A JP 5304502A JP 30450293 A JP30450293 A JP 30450293A JP 3046188 B2 JP3046188 B2 JP 3046188B2
- Authority
- JP
- Japan
- Prior art keywords
- container
- drum
- compressed air
- airtight leak
- inspection
- Prior art date
- 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.)
- Expired - Lifetime
Links
Landscapes
- Examining Or Testing Airtightness (AREA)
Description
【0001】[0001]
【産業上の利用分野】本発明は鋼製ドラム等容器の気密
漏洩試験方法及びその装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for testing airtight leakage of containers such as steel drums.
【0002】[0002]
【従来の技術】従来、鋼製ドラムはJIS Z−160
1(鋼製ドラム)に規定しているように、鋼板を円筒形
に成形した後、溶接をした胴体の上下端に注入口及び換
気口となる口金を取り付けた天板と底になる地板を巻き
締めて製造される。その容器は通常20〜200lまで
あり、液体の容器として用いられている。この容器の機
能として最も重要なことは、内容物をドラムに収納した
後、運搬或いは保管中に内容物が漏洩しないことであ
る。そのために、ドラム等容器の製造工程の中で行われ
る気密試験は重要な品質管理試験であり、JIS Z
1901にもゲージ圧30kPaの圧縮空気を容器内に
送り込み、水中に浸す(水没試験)かまたは石鹸水を塗
布して漏れの有無を検査する気密試験及び容器内に水を
注入して、250kPaのゲージ圧で5分間試験し、漏
れの有無を調べる水圧試験の規定がある。2. Description of the Related Art Conventionally, steel drums have been used in accordance with JIS Z-160.
As specified in 1 (steel drum), after a steel plate is formed into a cylindrical shape, a top plate with a base serving as an inlet and a vent is attached to the upper and lower ends of the welded fuselage, and a base plate serving as a bottom is attached. It is manufactured by winding. The container usually has a capacity of 20 to 200 l and is used as a liquid container. The most important function of the container is to prevent the contents from leaking during transportation or storage after the contents are stored in the drum. Therefore, the airtightness test performed in the manufacturing process of containers such as drums is an important quality control test, and JIS Z
Also in 1901, compressed air with a gauge pressure of 30 kPa is sent into the container and immersed in water (submerged test) or applied with soapy water to check for leaks, and water is injected into the container, and water is injected into the container at 250 kPa. There is a provision of a water pressure test for testing for 5 minutes at a gauge pressure to check for leaks.
【0003】また、鋼製ドラム等容器の製造ラインの中
で、気密試験の全数試験が行われているのが一般的であ
る。このライン内での試験に用いられる方法には、容器
内に圧縮空気を封入し、試験個所に石鹸水を塗布すると
漏れがある場合に生ずる泡を肉眼で見て検査する石鹸水
試験、容器内に圧縮空気を封入するか、もしくは容器の
外側を覆う密閉外蓋内を減圧して容器内の圧力変化を検
知して漏れの有無を検査する差圧式漏洩試験機及び容器
内に封入したヘリュウムガスの漏洩程度を検知して漏れ
の有無を検査するヘリュウム式漏洩試験機の3通りがあ
る。[0003] In a production line for containers such as steel drums, it is common practice to carry out a 100% airtightness test. The method used for testing in this line includes a soap water test, in which compressed air is sealed in a container, and when a test solution is applied with soapy water, bubbles generated when there is a leak are visually inspected. A differential pressure type leak tester and a helium gas sealed in a container, in which compressed air is filled in, or the inside of a sealed outer lid that covers the outside of the container is depressurized to detect a change in pressure inside the container and to check for leaks. There are three types of helium-type leak testers that detect the degree of leakage and check for the presence or absence of leakage.
【0004】[0004]
【発明が解決しようとする課題】上述した従来から広く
用いられている漏洩試験のうち、石鹸水試験は熟練した
検査者が行うと、極めて鋭敏な検査方法であって、容器
に生じた直径が0.005mm程度の微小な孔まで検出
することが出来て、実用的には全く問題がない。しか
し、漏洩箇所から発生する石鹸水の微小な泡を肉眼で観
察して漏洩の有無を検査するので、検査者の熟練度合い
や疲労度合いによって検査結果に変動を生じる点が問題
である。Among the above-mentioned leak tests that have been widely used in the past, the soapy water test is an extremely sensitive inspection method performed by a skilled inspector, and the diameter generated in the container is small. As small as 0.005 mm can be detected, and there is no problem in practice. However, since the presence or absence of leakage is inspected by visually observing minute bubbles of soap water generated from the leak location, there is a problem in that the inspection result varies depending on the skill level and fatigue level of the inspector.
【0005】また、容器に生じた孔が直径で1mm前後
の大きな孔の場合には漏れる空気量が多く、石鹸水の泡
が直ぐに破壊してしまうために漏れを見逃し易いという
欠点がある。差圧式漏洩試験機は検知可能な孔が直径で
0.2mm以上の比較的大きな場合には有効であるが、
微小な孔の場合には検知精度が悪い。また、検知精度を
上げるためには鋭敏な圧力センサーが必要である。一
方、ヘリュウム式漏洩試験機は検知する孔の大きさは直
径0.005mm程度の微小な孔まで検出は可能であ
り、検査機器としては優れているが、装置費用が高価で
あること、及び容器内に封入するヘリュウム使用による
経費が他の試験方法に比較して高いという欠点がある。[0005] Further, when the hole formed in the container is a large hole having a diameter of about 1 mm, a large amount of air leaks, and there is a disadvantage that the leak is easily overlooked because the soapy water bubbles are destroyed immediately. The differential pressure type leak tester is effective when the detectable hole is relatively large with a diameter of 0.2 mm or more,
In the case of minute holes, the detection accuracy is poor. In addition, a sharp pressure sensor is required to increase the detection accuracy. On the other hand, the helium-type leak tester is capable of detecting holes as small as 0.005 mm in diameter, and is excellent as an inspection device, but the equipment cost is high, and The disadvantage is that the cost of using helium encapsulated inside is higher than other test methods.
【0006】[0006]
【課題を解決するための手段】そこで発明者らは鋭意工
夫を重ねた結果、これらの問題点を解消すべき開発した
もので、容器内に封入した圧縮空気が孔から漏れる時に
振動によって生じる超音波を検知する方法で漏れの有無
を自動的に検査する方法及びその装置である。その発明
の要旨とするところは、 (1)容器内に圧縮空気を封入又は減圧、或いは容器を
覆う密閉外蓋内に圧縮空気を封入又は減圧して、容器の
内圧と外圧との差を0.5〜2.0kgf/cm 2 にす
ることによって、容器の内部から外部に又は逆方向に空
気が漏れる時に生ずる容器本体を伝播する100〜30
0kHzの波動を容器に接触するセンサーにより検知し
て、容器の気密漏洩を検査することを特徴とする容器の
気密漏洩試験方法。Means for Solving the Problems Therefore, the inventors have eagerly worked.
As a result of repeated husbands, we developed to solve these problems
When the compressed air enclosed in the container leaks from the hole
Leakage is detected by detecting ultrasonic waves generated by vibration
And a device for automatically inspecting the data. The invention
(1) Enclose or decompress compressed air in the container, or place the container
Enclose or reduce the pressure of compressed air in the sealed outer lid to
The difference between the internal pressure and the external pressure is 0.5 to 2.0 kgf / cm TwoNasu
To empty from the inside of the container to the outside or in the opposite direction.
Propagating the container body that occurs when air leaks 100-30
0kHz wave is detected by a sensor that contacts the container.
Inspection of the container for leaks.
Airtight leak test method.
【0007】(2)容器の天板部及び地板部を弾性体物
質を介した治具で容器を保持固定して、他の機械装置か
らの振動を遮断した状態で、容器内に圧縮空気を注入或
いは容器外で容器を覆う密閉外蓋内の空気を排出して、
容器の気密漏洩を検査することを特徴とする容器の気密
漏洩試験装置。 (3)前記(1)による気密漏洩試験において、容器の
内面または外面もしくは内外面の一部または全面を液状
体で濡らした状態で容器の気密を検査することを特徴と
する気密漏洩試験方法にある。(2) With the top and bottom plates of the container held and fixed by means of a jig via an elastic material, compressed air is blown into the container while vibrations from other mechanical devices are cut off. Inject or vent the air in the sealed outer lid that covers the container outside the container,
An airtight leak test apparatus for a container, which inspects the airtight leak of the container. (3) In the airtight leak test according to (1),
Liquid inside or outside or part or whole of inside and outside
It is characterized by inspecting the airtightness of the container while wet with the body
The leak test method .
【0008】[0008]
【作用】以下本発明について詳細に説明する。物が破壊
するときに音が発するが固体が破壊に至る以前の小さな
変形や振動、微小なクラックの発生や進展に伴って、人
には聞こえない数kHzから数MHzの微弱な超音波が
発生する。これをアコーステイック・エミッション(以
下AEと略記する)といわれ、「固体の変形及び破壊に
伴って開放されるエネルギーが音響パルスとなり、伝播
する現象」と定義されている。これまで材料の塑性変形
や破壊機構の解明のための研究や切削・研磨中の工具損
傷監視用として応用されていたが、このAEを容器の気
密漏洩試験機に適用したのが本発明のAE式気密漏洩試
験機で、容器の内部から空気が漏れるときに生じる微細
な容器本体の振動や容器の表面を濡らす液体の膜が破壊
するときに生じる微小な破壊音が容器本体を伝播するの
を検知して容器の漏洩を検知する方式である。The present invention will be described below in detail. A sound is emitted when an object is destroyed, but weak ultrasonic waves of several kHz to several MHz that cannot be heard by humans are generated due to small deformation and vibration before the solid is destroyed, and the generation and development of minute cracks. I do. This is called acoustic emission (hereinafter abbreviated as AE), and is defined as "a phenomenon in which energy released due to deformation and destruction of a solid becomes an acoustic pulse and propagates". Until now, the AE of the present invention has been applied to research for elucidating the plastic deformation and fracture mechanism of materials and for monitoring tool damage during cutting and polishing. With the airtight type leak tester, it is possible to prevent the minute vibration of the container body that occurs when air leaks from the inside of the container and the minute breaking sound that occurs when the film of the liquid that wets the surface of the container breaks, from propagating through the container body. This is a method of detecting leakage of a container by detecting.
【0009】図1はAE式気密漏洩試験機の概略図であ
る。図1(A)はAE式気密漏洩試験機の横断面図であ
り、図1(B)は同正面断面図である。このAE式気密
漏洩試験機を使用したAE式気密漏洩試験機のブロック
図とフローチャートを鋼製ドラムへの適用例をもとに図
2及び図3で説明する。すなわち、図2はAE式気密漏
洩試験機の信号処理ブロック図である。また、図3は検
査のフローチャート図である。なお、以下の説明ではド
ラムが横置きにした状態で搬送する製缶工程であるが、
これは横置きに限定されるものではなく、ドラムは竪置
きの状態で搬送される製缶工程では、それに応じた対応
をすれば良く、特にいずれかにも限定されるものではな
い。而して、図1(A)及び(B)に示すように、ドラ
ム1は横置きにした状態でチェーンコンベア2上を搬送
されて気密漏洩試験機3の所に搬送される。ここで上下
に昇降する架台4に支えられて所定の位置にドラムの高
さを設定してから、油圧又は空気圧で左右に開閉するデ
ィスク5或いはアーム等の治具によってドラムの天板6
及び地板側を保持固定し架台は下降する。FIG. 1 is a schematic view of an AE type airtight leak tester. FIG. 1A is a cross-sectional view of the AE type airtight leak tester, and FIG. 1B is a front cross-sectional view of the same. A block diagram and a flow chart of the AE type airtight leak tester using the AE type airtight leak tester will be described with reference to FIGS. 2 and 3 based on an example of application to a steel drum. That is, FIG. 2 is a signal processing block diagram of the AE type airtight leak tester. FIG. 3 is a flowchart of the inspection. In the following description, the drum making process in which the drum is transported in a horizontal state,
This is not limited to the horizontal placement, and the drum making process in which the drum is transported in the vertical position may be performed in accordance with the process, and is not particularly limited to any one. Thus, as shown in FIGS. 1A and 1B, the drum 1 is conveyed on the chain conveyor 2 in a state of being laid horizontally, and conveyed to the airtight leak tester 3. Here, the height of the drum is set at a predetermined position while being supported by the gantry 4 that moves up and down, and then the top plate 6 of the drum is set by a jig such as a disk 5 or an arm that opens and closes left and right by hydraulic or pneumatic pressure.
Then, the base plate is held and fixed, and the gantry descends.
【0010】固定治具はゴム板7等の弾性体物質を介し
てドラムを保持固定する。ドラムにディスクやその他の
装置部品を構成する金属部品が接触していると、搬送コ
ンベアの動きや同じ工場内にある他の機械類の動き、或
いはドラム同志の接触に伴って発生する超音波が伝播し
て雑音として入り、検査精度を低下させるので好ましく
ない。ゴムは周辺の振動や音を遮断でき、一方、ドラム
の天板及び地板をクランプする圧力で圧縮されない程度
の硬さが必要であり、スプリング式硬さ試験機A型で7
0〜90の硬さの材料が好ましい。The fixing jig holds and fixes the drum via an elastic material such as a rubber plate 7. If the drum is in contact with the metal parts that make up the disc or other device parts, the ultrasonic waves generated by the movement of the conveyor, the movement of other machinery in the same factory, or the contact between the drums This is undesirable because it propagates as noise and lowers the inspection accuracy. The rubber can block the vibration and sound of the surroundings. On the other hand, the rubber needs to have a hardness not to be compressed by the pressure for clamping the top plate and the base plate of the drum.
Materials with a hardness of 0 to 90 are preferred.
【0011】固定治具がディスクの場合にはドラムのチ
ャイム8の高さより厚い30mm程度のゴム板が取り付
けてあり、ドラムの天地板の面上で保持固定する。ドラ
ムの中に高圧の圧縮空気を封入すると、天地板側が先に
膨張し、次いで胴体部が膨張して永久変形を起こすの
で、適切な圧力に設定する必要があるが、この保持固定
方式では最も変形し易い天地板の膨張を抑制する効果が
あるので、比較的高い内圧で検査が出来るので検査の精
度が高くなるという特徴がある。ゴム板はチャイム部の
先端でドラムを保持してもよいが、大きな圧力で押し付
けられてゴム板の損耗が大きいので天地板の平面部で保
持する方が良い。この場合ゴム板は天地板の全面に接触
するのではなく、ゴム板に部分的に孔をくり貫いておい
ても良い。When the fixing jig is a disc, a rubber plate of about 30 mm thicker than the height of the drum chime 8 is attached, and is held and fixed on the top plate of the drum. If high-pressure compressed air is sealed in the drum, the top and bottom plates expand first, and then the body expands and causes permanent deformation, so it is necessary to set an appropriate pressure. It has the effect of suppressing the expansion of the top plate which is easily deformed, so that the inspection can be performed with a relatively high internal pressure, so that the inspection accuracy is improved. The rubber plate may hold the drum at the tip of the chime portion, but it is better to hold the drum on the top surface of the top plate because the rubber plate is pressed by a large pressure and the rubber plate is greatly worn. In this case, the rubber plate does not come into contact with the entire surface of the top and bottom plates, but may partially penetrate the rubber plate.
【0012】ゴム板が天地板の全面に接していると、も
し天地板に孔があった場合には、その孔をゴム板で塞い
でしまい孔が検出できなくなるので、天地板の面との接
触はドラムを保持する強度上可能な限り狭い方が望まし
い。また、ドラムの天地側には注入口9と換気口10に
なる口金が取り付けてあり、天地側のディスクに取り付
けた配管により注入された圧縮空気が口金からドラム内
に封入されるか、空気を排出するために、その口金を塞
がないようにしてゴム板には口金部に相当する孔をくり
貫き、空気の通路を確保しておく必要がある。If the rubber plate is in contact with the entire surface of the top plate, if there is a hole in the top plate, the hole is closed with the rubber plate and the hole cannot be detected. It is desirable that the contact be as narrow as possible in terms of strength for holding the drum. Further, a base serving as an inlet 9 and a ventilation opening 10 is attached to the top and bottom sides of the drum, and compressed air injected by a pipe attached to the top side disk is sealed in the drum from the base or the air is supplied. In order to discharge the air, it is necessary to open the hole corresponding to the base portion in the rubber plate so as not to cover the base and to secure an air passage.
【0013】固定治具がアームの場合には、ゴムで覆わ
れたアームの先端でドラムを保持固定するので、ドラム
表面の開放部面積が大きく、検査出来る容器の面積が大
きくなるという特徴がある。しかし、この方法では封入
する圧縮空気の圧力が大きくなると、ドラムの天地板の
変形を抑制出来ないので、内圧は低くせざるを得ない。
また、この方式で容器の天地側の保持固定する場合に
は、口金の換気口側は予め密栓をしておき、注入口側か
ら空気を注入、或いは排出する配管を直接に接続する装
置とする。When the fixing jig is an arm, the drum is held and fixed at the tip of the arm covered with rubber, so that the area of the open portion of the drum surface is large and the area of the container that can be inspected is large. . However, in this method, if the pressure of the compressed air to be filled becomes large, the deformation of the top plate of the drum cannot be suppressed, so that the internal pressure must be reduced.
In addition, in the case of holding and fixing the container on the top and bottom sides by this method, the ventilation port side of the base is sealed in advance, and a device for directly injecting or discharging air from the injection port side is used as a device. .
【0014】容量200lの鋼製ドラム1種は厚さが
1.0mmから1.6mmの鋼板を使用するL級からH
級まであり、また、ドラムの外面は一般的に塗装されて
いるが、内面は化成処理のままの場合と化成処理をした
後で塗装をしたものとある。また、鋼板には亜鉛めっき
鋼板或いはステンレス鋼板を使用して製缶し、内外面が
無塗装のものがある。これらの各種のドラムについて各
種条件で試験を行った結果を基に、内部に圧縮空気を封
入する場合、圧力はゲージ圧で0.5〜2.0kgf/
cm2 、望ましくは0.7〜1.2kgf/cm2 の空
気を封入する。空気圧は高い程漏洩の検査精度は高まる
が、一方、内圧が大きくなるとドラムの変形を防止する
ための天地板の保持固定用ディスクの油圧機構を大きな
能力にする必要があるので、適切な圧力を選定すること
が望ましい。One type of steel drum having a capacity of 200 liters uses a steel plate having a thickness of 1.0 mm to 1.6 mm and uses a class of L to H.
The outer surface of the drum is generally coated, but the inner surface may be left as it is after the chemical conversion treatment or may be coated after the chemical conversion treatment. Further, some steel sheets are made of galvanized steel sheet or stainless steel sheet, and the inner and outer surfaces are unpainted. Based on the results of tests performed on these various drums under various conditions, when compressed air is sealed inside, the pressure is 0.5 to 2.0 kgf / gauge.
The air of cm 2 , desirably 0.7 to 1.2 kgf / cm 2 is enclosed. The higher the air pressure, the higher the leakage inspection accuracy.On the other hand, if the internal pressure increases, the hydraulic mechanism of the disk holding and fixing the top and bottom plates to prevent deformation of the drum must have a large capacity. It is desirable to select.
【0015】また、各種ドラムについて鋼板や溶接部、
或いは巻き締め部に生じた漏洩部分や孔の大きさについ
て漏洩試験を行い、発生するAE信号を分析した結果、
100kHz〜400kHzまでの超音波が発生してお
り、ドラムの塗装の有無や漏洩箇所及び孔の大きさによ
って強弱の違いはあるが、いずれも200kHz前後の
信号の発生が顕著であることが判明した。すなわち、2
00kHzの信号を優先的に検知するようなフイルター
を使用すれば、他の機械や衝突音による雑音は比較的効
果的に除去できて検査精度が向上することがわかった。Further, for various drums, a steel plate, a welded portion,
Alternatively, a leak test was performed on the size of the leaked portion and the hole generated in the tightened portion, and as a result of analyzing the generated AE signal,
Ultrasonic waves from 100 kHz to 400 kHz are generated, and there is a difference in strength depending on the presence or absence of coating on the drum, the leakage location and the size of the hole, but it was found that the generation of signals around 200 kHz was remarkable in each case. . That is, 2
It was found that if a filter that preferentially detects a signal of 00 kHz is used, noise due to other machines or collision noise can be removed relatively effectively, and inspection accuracy improves.
【0016】AEセンサー11は容器の表面に接触し
て、容器本体を伝播してくる弾性振動を電気的な信号に
変換するもので、セラミックス圧電体から出来ている直
径10mm程度の円形体である。どの方向のAE信号も
検知出来るように無指向性になっている。センサーを容
器の表面に接触する際に、センサーと容器の表面との間
に空気層があると信号の減衰が生じるので、センサーの
表面をグリセリン或いは界面活性剤の水溶液か水の薄層
を設ける必要がある。本発明の実施例ではドラムの製造
ライン内での連続的な検査が可能なように、水の薄層を
設ける方式を採用している。すなわち、センサーの周辺
に高さで0.8mmだけ高いゴム製のリングとそれに接
続する注水配管を設けており、注水配管から供給された
水はゴムリングで囲まれたセンサーの表面に一定量分が
留まり、過剰分はゴムリングの一部に設けたスリットか
らオーバーフローして排出される。The AE sensor 11 converts an elastic vibration propagating through the container body into an electrical signal by contacting the surface of the container, and is a circular body having a diameter of about 10 mm made of a ceramic piezoelectric body. . It is omnidirectional so that AE signals in any direction can be detected. When contacting the sensor with the surface of the container, if there is an air layer between the sensor and the surface of the container, signal attenuation will occur, so provide a thin layer of glycerin or a surfactant aqueous solution or water on the sensor surface. There is a need. The embodiment of the present invention employs a method of providing a thin layer of water so that a continuous inspection can be performed in a drum production line. That is, a rubber ring high by 0.8 mm in height and a water injection pipe connected to the rubber ring are provided around the sensor, and a certain amount of water supplied from the water injection pipe is distributed on the surface of the sensor surrounded by the rubber ring. Remains, and the excess is discharged by overflowing from a slit provided in a part of the rubber ring.
【0017】このような構造のセンサーをエアーシリン
ダー12で昇降出来るようにしており、容器本体の下部
からセンサーを押し付けると、センサーはゴムリングの
厚さ分だけ一定の間隔を置き、容器に水の層を介して接
触するこことなる。鋼製ドラムであれば検査する容器1
個に対してセンサーは1個で十分であるが、センサーの
誤動作による検査ミスを回避するために、本実施例では
センサーと以下に述べる電気回路も含めて2系統を設け
て、少なくとも、いずれかの1個で漏洩が検知出来たら
不合格と判定することにしている。また、センサーは発
生する超音波の周波数に応じて、適当な周波数特性や感
度をもつものを選択するが、本実施例では前述のように
鋼製ドラムでは200kHzの周波数が最も顕著であっ
たので、周波数帯域が50kHz〜1MHzで200k
Hz共振型で防水型のものを使用している。The sensor having such a structure can be moved up and down by the air cylinder 12. When the sensor is pressed from the lower part of the container body, the sensor is placed at a fixed interval corresponding to the thickness of the rubber ring, and water is supplied to the container. It will come in contact through the layers. Container 1 to be inspected if it is a steel drum
Although one sensor is sufficient for each sensor, in order to avoid an inspection error due to a malfunction of the sensor, in this embodiment, two systems including a sensor and an electric circuit described below are provided, and at least one of the sensors is provided. If a leak is detected by one of the above, it is determined to be rejected. In addition, a sensor having an appropriate frequency characteristic and sensitivity is selected according to the frequency of the generated ultrasonic wave. In the present embodiment, the frequency of 200 kHz is most prominent in the steel drum as described above. , 200k in the frequency band of 50kHz to 1MHz
Hz resonance type and waterproof type are used.
【0018】次いで、図2に示すようにセンサーで弾性
振動を電気信号に変換した微小電圧をプリアンプで増幅
した後、AE信号とともに入って来た周辺の機械的な雑
音をフィルターを通すことによって、妨害する雑音を押
さえて必要な周波数成分の信号だけを取り出す。機械的
振動等の環境雑音は低周波数のものが多いので、フィル
ターによって数10kHz以下の周波数信号を遮断す
る。周辺雑音の中の容器の漏洩に基づく信号に最も類似
した周波数で誤判定し易いのは、容器に中に圧縮空気を
注入する時に発生する雑音である。そこで後述のように
圧縮空気を注入する間に、センサーの動作が正常か否か
のテストする装置診断を行うことにしている。すなわ
ち、圧縮空気を注入する0.5〜0.7秒の間にAE信
号を検知すればセンサーの動作は正常と判断し、信号の
検知がなければセンサーの動作不良と判断して装置の点
検を行うことにしている。Next, as shown in FIG. 2, a minute voltage obtained by converting the elastic vibration into an electric signal by the sensor is amplified by a preamplifier, and then the surrounding mechanical noise coming in with the AE signal is passed through a filter. Suppress the disturbing noise and extract only the signal of the necessary frequency component. Many environmental noises such as mechanical vibrations have low frequencies, so that a filter blocks a frequency signal of several tens of kHz or less. A noise that is likely to be erroneously determined at a frequency most similar to a signal based on leakage of a container in ambient noise is noise generated when compressed air is injected into the container. Therefore, as will be described later, while injecting the compressed air, a device diagnosis for testing whether or not the operation of the sensor is normal is performed. In other words, if the AE signal is detected within 0.5 to 0.7 seconds during which compressed air is injected, the sensor operation is determined to be normal, and if no signal is detected, the sensor operation is determined to be malfunctioning and the device is inspected. I'm going to do.
【0019】圧縮空気を注入して所定の圧力に達してか
ら0.1秒ないし2秒後に漏洩検査を開始する。検査は
1.0秒ないし2.5秒間行い、100m秒毎に予め設
定した閾値よりも大きな信号を検知した回数を計測(設
定値を超えたピークの数をリング・ダウン、略してRD
という)して検査時間内の累積値を自動的に求め、更に
予め設定した警報設定値と比較して、それよりも大きな
RD値の場合は不合格と判定して警報を発する。大きな
孔からの漏洩の場合には、短時間でRDが警報設定値を
超えるが、微小な孔の場合には、濡れがあっても所定の
検査時間内ではRDは警告設定値に達しないので合格と
判定する。従って、検査に掛けられる時間が長い程、漏
洩を検知出来る孔の大きさは小さくなり、検査精度は良
くなるが、検査時間は直接生産性に影響するので、適切
なところで検査時間を決めることが必要である。The leak inspection is started 0.1 second to 2 seconds after the predetermined pressure is reached by injecting the compressed air. The inspection is performed for 1.0 to 2.5 seconds, and the number of times that a signal larger than a preset threshold is detected every 100 ms is measured (the number of peaks exceeding the set value is ring-down, abbreviated as RD).
Then, the accumulated value within the inspection time is automatically obtained, and is compared with a preset alarm set value. If the RD value is larger than the set value, it is determined to be unacceptable and an alarm is issued. In the case of leakage from a large hole, the RD exceeds the alarm set value in a short time, but in the case of a small hole, the RD does not reach the alarm set value within a predetermined inspection time even if there is wetness. Judge as pass. Therefore, the longer the time taken for the inspection, the smaller the size of the hole where the leak can be detected and the higher the inspection accuracy, but the inspection time directly affects productivity, so it is necessary to determine the inspection time at an appropriate place. is necessary.
【0020】また、漏洩する容器の内面或いは外面が水
や界面活性剤の水溶液のような液体で濡れているとき
に、圧縮空気が注入されると、漏洩箇所から空気が漏れ
るよりも先に容器を濡らしている液体の膜が破壊して、
その際にも同様のAE信号を発する。従って、2秒間の
検査時間では所定の警報設定値に達するRD値が発生し
ないような微小な孔がある容器でも、容器の内面或いは
外面が液体で濡れている場合は短時間で警報設定値を超
える信号を検知することが出来る。すなわち、容器の内
面或いは外面を液体で濡らすことによって、検知出来る
孔の大きさの限界が向上し、検査時間を短縮できる効果
がある。Further, when the compressed air is injected when the inner or outer surface of the leaking container is wet with a liquid such as water or an aqueous solution of a surfactant, the container may leak before the air leaks from the leak location. The film of liquid wetting breaks down,
At this time, a similar AE signal is issued. Therefore, even if the container has minute holes so that the RD value does not reach the predetermined alarm setting value in the inspection time of 2 seconds, if the inner surface or the outer surface of the container is wet with the liquid, the alarm setting value is quickly set. It is possible to detect a signal exceeding it. That is, by wetting the inner surface or the outer surface of the container with the liquid, the limit of the size of the hole that can be detected is improved, and the inspection time is shortened.
【0021】このような効果を具体的に活用するため
に、本発明では次のような装置を工夫している。すなわ
ち、鋼製ドラムの場合、最も漏洩検査が必要で、かつ、
微小な孔を生じ易い胴の溶接線部と天板及び地板の巻き
締め部には、検査直前に容器の下部及び上部両端部に設
けたノズル13、14から水を噴霧又は滴下して当該箇
所が水で濡れるようにしてある。当然のことながら、こ
の後で濡れた水を拭い取るか、乾燥をする装置が必要が
ある。この結果、乾燥した容器の場合に、2秒の検査時
間内でRD値は13であったが、水で濡らした場合は2
57であった。AE信号の発生度合いは、前述のように
影響されるので、生産速度が大きい工場での検査では、
検査時間を短縮する必要があるので、内圧を高くして、
容器の外面を濡らす方案が有効であるが、それだけ設備
費用は高くなる。一方、生産速度が小さい工場では検査
時間を長くすることが可能なので、内圧を小さくし、水
で濡らすことも必要でないので設備費用を易くすること
ができる。それぞれの事情によって適切な設備仕様と検
査条件を設定出来る。In order to specifically utilize such effects, the present invention devises the following apparatus. That is, in the case of a steel drum, the leak inspection is most necessary, and
Water is sprayed or dropped from the nozzles 13 and 14 provided at the lower and upper ends of the container immediately before the inspection at the weld line portion of the body where small holes are likely to be formed and the tightened portion of the top plate and the base plate. Is made to get wet with water. Of course, after this, a device for wiping or drying the wet water is required. As a result, the RD value of the dried container was 13 within the inspection time of 2 seconds.
57. Since the degree of occurrence of the AE signal is affected as described above, in the inspection at a factory where the production speed is high,
Since it is necessary to shorten the inspection time, raise the internal pressure,
The method of wetting the outer surface of the container is effective, but increases the equipment cost accordingly. On the other hand, in a factory where the production speed is low, the inspection time can be lengthened, so that the internal pressure is reduced and it is not necessary to wet with water, so that the facility cost can be simplified. Appropriate equipment specifications and inspection conditions can be set according to each situation.
【0022】[0022]
【実施例】JIS Z1601に規定してある試験法に
従って、ゲージ圧30kPa(0.3kgf/cm2 )
の圧縮空気を送り込み、これを水中に浸して漏れの有無
を検査する気密試験で不合格であった鋼製ドラム1種M
級(板厚1.2mm)で内面は無塗装、外面は塗装した
缶を、図3に示すような操作手順によって気密漏洩試験
装置に移動・停止し、センサーを上昇後、内圧0.7k
gf/cm2 の圧縮空気を封入してセンサーテスト開始
し、異常のないことを確認後で、センサーテスト停止
し、引続き漏洩検査を開始した。100msec毎にR
Dを測定し、警報設定値と比較して異常な警報を出力し
検査値をメモリに記憶させ、その結果は2秒間でRD値
335をカウントして不合格である結果を得た。その後
は漏洩検査を停止し、容器の空気を排除しセンサーを下
降し終了する。EXAMPLE According to the test method specified in JIS Z1601, the gauge pressure is 30 kPa (0.3 kgf / cm 2 ).
1 type of steel drum M which failed in the airtightness test to send compressed air and immerse it in water to check for leaks
After moving the cans of grade (plate thickness 1.2mm) with no coating on the inner surface and painted on the outer surface to the airtight leak tester according to the operation procedure shown in Fig. 3, raising the sensor, the internal pressure was 0.7k.
The sensor test was started by injecting compressed air of gf / cm 2 , and after confirming that there was no abnormality, the sensor test was stopped and the leak test was subsequently started. R every 100 msec
D was measured and compared with the alarm set value, an abnormal alarm was output, and the inspection value was stored in the memory. The result was that the RD value 335 was counted in 2 seconds and the result was rejected. After that, the leak inspection is stopped, the air in the container is eliminated, the sensor is lowered, and the process ends.
【0023】[0023]
【発明の効果】以上述べたように、本発明による容器内
に封入した圧縮空気が孔から漏れる時に振動によって生
じる超音波を検知する方法によって、人手を必要とせず
自動的に精度良く容易に容器の気密漏洩を検査すること
が出来る、工業上極めて有利な方法及びその装置を提供
することある。As described above, according to the method of the present invention for detecting ultrasonic waves generated by vibration when compressed air enclosed in a container leaks from a hole, a container can be automatically and accurately and easily prepared without requiring any manual operation. It is an object of the present invention to provide an industrially advantageous method and apparatus capable of inspecting for airtight leaks.
【図1】AE式気密漏洩試験機の概略図、FIG. 1 is a schematic diagram of an AE type airtight leak tester,
【図2】AE式気密漏洩試験機の信号処理ブロック図、FIG. 2 is a signal processing block diagram of an AE type airtight leak tester,
【図3】検査のフローチャート図である。FIG. 3 is a flowchart of an inspection.
1 ドラム 2 チェーンコンベア 3 気密漏洩試験機 4 架台 5 ディスク 6 天板 7 ゴム板 8 チャイム 9 注入口 10 換気口 11 AEセンサー 12 エアーシリンダー 13、14 ノズル DESCRIPTION OF SYMBOLS 1 Drum 2 Chain conveyor 3 Airtight leak tester 4 Stand 5 Disk 6 Top plate 7 Rubber plate 8 Chime 9 Inlet 10 Ventilation port 11 AE sensor 12 Air cylinder 13, 14 Nozzle
フロントページの続き (56)参考文献 特開 昭63−249033(JP,A) 特開 昭50−2589(JP,A) 特開 平4−25739(JP,A) (58)調査した分野(Int.Cl.7,DB名) G01M 3/24 G01M 3/26 Continuation of the front page (56) References JP-A-63-249033 (JP, A) JP-A-50-2589 (JP, A) JP-A-4-25739 (JP, A) (58) Fields investigated (Int .Cl. 7 , DB name) G01M 3/24 G01M 3/26
Claims (3)
は容器を覆う密閉外蓋内に圧縮空気を封入又は減圧し
て、容器の内圧と外圧との差を0.5〜2.0kgf/
cm2 にすることによって、容器の内部から外部に又は
逆方向に空気が漏れる時に生ずる容器本体を伝播する1
00〜300kHzの波動を容器に接触するセンサーに
より検知して、容器の気密漏洩を検査することを特徴と
する容器の気密漏洩試験方法。1. A method in which compressed air is sealed or decompressed in a container, or compressed air is sealed or decompressed in a closed outer cover for covering a container, so that a difference between an internal pressure and an external pressure of the container is 0.5 to 2.0 kgf /.
cm 2 to propagate through the container body when air leaks from the inside of the container to the outside or in the opposite direction.
An airtight leak test method for a container, wherein a wave of 00 to 300 kHz is detected by a sensor contacting the container, and the airtight leak of the container is inspected.
介した治具で容器を保持固定して、他の機械装置からの
振動を遮断した状態で、容器内に圧縮空気を注入或いは
容器外で容器を覆う密閉外蓋内の空気を排出して、容器
の気密漏洩を検査することを特徴とする容器の気密漏洩
試験装置。2. Compressed air is injected into the container in a state where the container is held and fixed with a jig via an elastic material on a top plate portion and a base plate portion of the container, and vibration from other mechanical devices is cut off. Alternatively, an airtight leak test apparatus for a container, characterized in that the air inside the sealed outer lid that covers the container is discharged outside the container and the airtight leak of the container is inspected.
容器の内面または外面もしくは内外面の一部または全面Part or all of the inner or outer surface or inner or outer surface of the container
を液状体で濡らした状態で容器の気密を検査することをTo inspect the airtightness of the container with the liquid wet.
特徴とする気密漏洩試験方法。Characteristic airtight leak test method.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5304502A JP3046188B2 (en) | 1993-12-06 | 1993-12-06 | Method and apparatus for testing airtight leakage of containers |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5304502A JP3046188B2 (en) | 1993-12-06 | 1993-12-06 | Method and apparatus for testing airtight leakage of containers |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH07159270A JPH07159270A (en) | 1995-06-23 |
JP3046188B2 true JP3046188B2 (en) | 2000-05-29 |
Family
ID=17933810
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP5304502A Expired - Lifetime JP3046188B2 (en) | 1993-12-06 | 1993-12-06 | Method and apparatus for testing airtight leakage of containers |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3046188B2 (en) |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR100411329B1 (en) * | 2001-08-21 | 2003-12-18 | 한국과학기술원 | Detector of pin-holes on vessel using microphone |
CN112977288B (en) * | 2019-12-12 | 2022-08-12 | 上汽通用汽车有限公司 | Acoustic performance development device for steering column via hole sealing member |
-
1993
- 1993-12-06 JP JP5304502A patent/JP3046188B2/en not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
JPH07159270A (en) | 1995-06-23 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP2008064745A (en) | Seal testing method, object to be inspected, and test stand | |
US6591680B2 (en) | System and method for ultrasonic immersion inspection of components | |
US11680857B2 (en) | Ultrasonic test device and test method for service stress of a moving mechanical component | |
EP1077370A2 (en) | A method of testing for a leak | |
JP2000214042A (en) | Non-pressure type leakage inspecting device | |
JP3046188B2 (en) | Method and apparatus for testing airtight leakage of containers | |
US5070724A (en) | Method for checking the tightness of a casing, and device for carrying out said method | |
GB2208713A (en) | Non-destructive elastic wave inspection method | |
JP3181811B2 (en) | Container airtight leak test method | |
JPS63285438A (en) | Test of air leak in liquid | |
JP3387577B2 (en) | Beer barrel leak inspection device | |
JPH11142279A (en) | Leak-inspecting apparatus of ultrasonic type | |
JP3680990B2 (en) | Acoustic reflector | |
JPS6128097B2 (en) | ||
JPS6359093B2 (en) | ||
KR100287706B1 (en) | Air cleaner testing apparatus | |
EP0390232B1 (en) | Process for checking the tightness of a casing, and device for carrying out said process | |
SU1709435A1 (en) | Method of testing of leak-proofness of chemical source of current | |
KR101416620B1 (en) | Leakage test apparatus using ultrasonic and air pressure | |
JPS60186753A (en) | Inspecting device for packing container | |
JPH11183303A (en) | Leak detecting method and device for container | |
JPS5817336A (en) | Inspecting method for air leakage in hose and device thereof | |
JPH08110329A (en) | Apparatus and method for inspecting pinhole | |
JP3725748B2 (en) | Ultrasonic pressureless leak tester | |
JPH0486537A (en) | Method and device for inspecting airtightness of casing |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20000307 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090317 Year of fee payment: 9 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100317 Year of fee payment: 10 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100317 Year of fee payment: 10 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110317 Year of fee payment: 11 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120317 Year of fee payment: 12 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130317 Year of fee payment: 13 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130317 Year of fee payment: 13 |
|
S533 | Written request for registration of change of name |
Free format text: JAPANESE INTERMEDIATE CODE: R313533 |
|
FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130317 Year of fee payment: 13 |
|
R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |