CH661124A5 - METHOD FOR MEASURING THE TIGHTNESS OF MULTIPLE WELDING SEAMS. - Google Patents
METHOD FOR MEASURING THE TIGHTNESS OF MULTIPLE WELDING SEAMS. Download PDFInfo
- Publication number
- CH661124A5 CH661124A5 CH1410/83A CH141083A CH661124A5 CH 661124 A5 CH661124 A5 CH 661124A5 CH 1410/83 A CH1410/83 A CH 1410/83A CH 141083 A CH141083 A CH 141083A CH 661124 A5 CH661124 A5 CH 661124A5
- Authority
- CH
- Switzerland
- Prior art keywords
- weld seams
- seams
- measuring
- tightness
- space
- Prior art date
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/82—Testing the joint
- B29C65/8207—Testing the joint by mechanical methods
- B29C65/8246—Pressure tests, e.g. hydrostatic pressure tests
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/10—Particular design of joint configurations particular design of the joint cross-sections
- B29C66/11—Joint cross-sections comprising a single joint-segment, i.e. one of the parts to be joined comprising a single joint-segment in the joint cross-section
- B29C66/112—Single lapped joints
- B29C66/1122—Single lap to lap joints, i.e. overlap joints
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/20—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines
- B29C66/23—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being multiple and parallel or being in the form of tessellations
- B29C66/232—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being multiple and parallel or being in the form of tessellations said joint lines being multiple and parallel, i.e. the joint being formed by several parallel joint lines
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/01—General aspects dealing with the joint area or with the area to be joined
- B29C66/05—Particular design of joint configurations
- B29C66/20—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines
- B29C66/24—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being closed or non-straight
- B29C66/242—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being closed or non-straight said joint lines being closed, i.e. forming closed contours
- B29C66/2424—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being closed or non-straight said joint lines being closed, i.e. forming closed contours being a closed polygonal chain
- B29C66/24243—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being closed or non-straight said joint lines being closed, i.e. forming closed contours being a closed polygonal chain forming a quadrilateral
- B29C66/24244—Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being closed or non-straight said joint lines being closed, i.e. forming closed contours being a closed polygonal chain forming a quadrilateral forming a rectangle
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C66/00—General aspects of processes or apparatus for joining preformed parts
- B29C66/40—General aspects of joining substantially flat articles, e.g. plates, sheets or web-like materials; Making flat seams in tubular or hollow articles; Joining single elements to substantially flat surfaces
- B29C66/41—Joining substantially flat articles ; Making flat seams in tubular or hollow articles
- B29C66/43—Joining a relatively small portion of the surface of said articles
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M3/00—Investigating fluid-tightness of structures
- G01M3/02—Investigating fluid-tightness of structures by using fluid or vacuum
- G01M3/26—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors
- G01M3/28—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for pipes, cables or tubes; for pipe joints or seals; for valves ; for welds
- G01M3/2884—Investigating fluid-tightness of structures by using fluid or vacuum by measuring rate of loss or gain of fluid, e.g. by pressure-responsive devices, by flow detectors for pipes, cables or tubes; for pipe joints or seals; for valves ; for welds for welds
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Examining Or Testing Airtightness (AREA)
Description
Die Erfindung bezieht sich auf ein Verfahren zur Messung der Dichtheit von zwei Bahnen aus flexiblem Kunststoffmaterial verbindenden Mehrfachschweissnähten, bei dem nach dem Anbringen von Quernähten in den Endbereichen der Mehrfachschweissnähte in den von den Schweissnähten umschlossenen Raum ein unter einem bestimmten Druck stehendes Medium eingebracht und der umschlossene Raum von der Druckmediumquelle getrennt wird. The invention relates to a method for measuring the tightness of two webs of flexible plastic material connecting multiple weld seams, in which after the application of transverse seams in the end areas of the multiple weld seams, a medium under a certain pressure is introduced into the space enclosed by the weld seams and the enclosed one Space is separated from the pressure medium source.
Insbesondere für die Isolierung von Tunnelwänden, Grundwasserwannen und Dächern werden häufig Kunststoff-Folien verwendet, wobei es notwendig ist, die einzelnen Bahnen dicht miteinander zu verschweissen. Dazu werden die Bahnen in der Regel durch zwei voneinander beabstan-dete, im wesentlichen parallel laufende Schweissnähte miteinander verschweisst. Um nun die Dichtheit einer solchen Mehrfachnaht zu überprüfen, wurden bisher nach dem Anbringen von Quernähten in den Endbereichen der Mehrfachschweissnähte in dem von den Schweissnähten umschlossenen Bereich in eine der Folien Öffnungen geschnitten und in diese ein zu einem Manometer führender Schlauch od. dgl. bzw. ein zu einer Druckgasquelle führender Schlauch eingeschweisst. Nach dem Einbringen des Druckgases in den von den Schweissnähten und den einander überlappenden Folien begrenzten Raum wurde die zur Druckgasquelle führende Leitung abgesperrt und das Manometer nach einer bestimmten Zeit wieder abgelesen, um einen gegebenenfalls über einem bestimmten Wert liegenden und daher eine Undichtheit anzeigenden Druckabfall feststellen zu können. Plastic foils are often used in particular for the insulation of tunnel walls, groundwater basins and roofs, it being necessary to weld the individual sheets tightly together. For this purpose, the webs are generally welded to one another by two weld seams which are spaced apart from one another and run essentially parallel. In order to check the tightness of such a multiple seam, openings have been cut into one of the foils in the area enclosed by the weld seams after the attachment of transverse seams in the end areas of the multiple weld seams and a hose or the like leading to a pressure gauge or the like has been cut into it. welded a hose leading to a compressed gas source. After the pressurized gas had been introduced into the space delimited by the weld seams and the overlapping foils, the line leading to the pressurized gas source was shut off and the pressure gauge was read again after a certain time in order to determine a pressure drop that was possibly above a certain value and therefore indicated a leak can.
Der Nachteil dieses Verfahrens besteht darin, dass nach Abschluss der Prüfung relativ grosse Öffnungen wieder verschweisst werden müssen, was mit erheblichem Aufwand verbunden ist. Ausserdem kann es bei Undichtheiten im Bereich der Einschweissungen der Schläuche zu unnötigen Fehleranzeigen kommen, die ein an sich unnötiges Nach-schweissen der Schweissnähte nach sich ziehen. Ziel der Erfindung ist es, ein Verfahren der eingangs erwähnten Art vorzuschlagen, das sich durch eine besonders einfache Durchführbarkeit auszeichnet und bei dem die Fehlerquellen auf ein Minimum reduziert sind. The disadvantage of this method is that relatively large openings have to be welded again after completion of the test, which is associated with considerable effort. In addition, in the event of leaks in the area of the welded-in areas of the hoses, unnecessary error displays can occur, which in themselves result in unnecessary re-welding of the weld seams. The aim of the invention is to propose a method of the type mentioned at the outset, which is particularly easy to carry out and in which the sources of error are reduced to a minimum.
Erfindungsgemäss wird dies dadurch erreicht, dass nach dem Einbringen des unter Druck stehenden Mediums an einer oder mehreren Stellen des von den Schweissnähten umschlossenen Raumes der Abstand der Aussenflächen der verschweissten Bahnen gemessen und dieser Abstand während oder nach einer vorgegebenen Zeitspanne auf eine eine Undichtigkeit anzeigende Abnahme hin untersucht wird. Auf diese Weise erübrigt sich das Einschweissen eines Anschlussschlauches für das Manometer, wodurch eine wesentliche Fehlerquelle eliminiert ist. Weiter lässt sich eine Undichtheit im Bereich der Schweissnähte durch eine Verminderung des Abstandes der Aussenflächen der verschweissten Bahnen einwandfrei nachweisen, wobei zur Messung des Abstandes z.B. übliche Messuhren, die meist eine Auflösung von 0,01 mm aufweisen, verwendet werden können. According to the invention, this is achieved in that after the introduction of the pressurized medium at one or more points in the space enclosed by the weld seams, the distance between the outer surfaces of the welded sheets is measured and this distance during or after a predetermined period of time indicating a decrease indicating a leak is examined. In this way there is no need to weld a connection hose for the pressure gauge, which eliminates a major source of errors. Furthermore, a leak in the area of the weld seams can be detected without any problems by reducing the distance between the outer surfaces of the welded sheets. Standard dial gauges, which usually have a resolution of 0.01 mm, can be used.
Nach einer weiteren Ausführungsform der Erfindung ist vorgesehen, dass das Druckmedium im Bereich einer Quernaht über eine Hohlnadel eingebracht wird. Damit wird erreicht, dass nach dem Abschluss der Prüfung der von den Schweissnähten eingeschlossene Raum leicht wieder geschlossen werden kann. Dazu genügt es, die meist sehr kurze Quernaht nachzuschweissen, was sehr einfach bewerkstelligt werden kann. Dabei ist noch zu berücksichtigen, dass bei Verwendung einer Hohlnadel zum Einbringen des Druckmediums praktisch die Anbringung eines Schweiss-punktes zum Schliessen der durch die Nadel hergestellten Öffnung in der Quernaht genügt. According to a further embodiment of the invention, it is provided that the pressure medium is introduced in the area of a transverse seam via a hollow needle. This ensures that the space enclosed by the welds can be easily closed again after the test has been completed. To do this, it is sufficient to re-weld the usually very short transverse seam, which can be done very easily. It should also be taken into account that when using a hollow needle to introduce the pressure medium, it is practically sufficient to attach a welding spot to close the opening made by the needle in the transverse seam.
Ein weiteres Ziel der Erfindung ist es, eine Messeinrichtung zur Durchführung des erfindungsgemässen Verfahrens vorzuschlagen. Erfindungsgemäss wird daher eine Messeinrichtung vorgeschlagen, die dadurch gekennzeichnet ist, dass sie durch eine zwei Backen aufweisende Klemmeinrichtung gebildet ist, bei der mindestens einer der Backen eine an der Klemmfläche offene Ausnehmung aufweist, in die ein Fühler einer Messeinrichtung eingreift. Another object of the invention is to propose a measuring device for carrying out the method according to the invention. According to the invention, therefore, a measuring device is proposed which is characterized in that it is formed by a clamping device having two jaws, in which at least one of the jaws has a recess which is open on the clamping surface and into which a sensor of a measuring device engages.
Die Erfindung wird nun an Hand der Zeichnung näher erläutert. Dabei zeigen: The invention will now be explained in more detail with reference to the drawing. Show:
Fig. 1 und 2 schematisch verschiedene Verfahrensschritte. 1 and 2 schematically different process steps.
Wie aus Figur 1 ersichtlich sind zwei Bahnen 1 und 2 von Kunststoff-Folien durch eine Doppelschweissnaht 3,4 miteinander verbunden. Ausserdem sind in den Endbereichen der Doppelschweissnaht 3,4 noch Quernähte 5,6 angeordnet. Dadurch entsteht ein von den Schweissnähten 3, 4, 5,6 begrenzter Raum zwischen den einander überlappenden Randbereichen der Bahnen 1 und 2. As can be seen from FIG. 1, two webs 1 and 2 of plastic films are connected to one another by a double weld seam 3, 4. In addition, transverse seams 5.6 are also arranged in the end regions of the double weld seam 3.4. This creates a space delimited by the weld seams 3, 4, 5, 6 between the overlapping edge regions of the webs 1 and 2.
Die Kontrolle auf Dichtheit der Doppelnaht 3,4 erfolgt erfindungsgemäss dadurch, dass z.B. an einem oder mehreren Punkten z.B. an den mit 11 und 12 bezeichneten Punkten eine Messeinrichtung angebracht wird. Eine geeignete derartige Messeinrichtung ist in Figur 2 dargestellt und besteht aus einer Schraubzwinge 14, deren einer Backen 15 eine an seiner Klemmfläche 16 offene Ausnehmung 17 aufweist, in die der Fühler 18 einer an der Schraubzwinge 14 befestigten Messuhr 13 hineinragt. Diese Messeinrichtung wird an einem beliebigen Punkt zwischen den Schweissnähten 3,4, 5 und 6 z.B. an dem Punkt 11 oder 12 festgeklemmt. The tightness of the double seam 3, 4 is checked according to the invention in that e.g. at one or more points e.g. a measuring device is attached to the points designated by 11 and 12. A suitable measuring device of this type is shown in FIG. 2 and consists of a screw clamp 14, one jaw 15 of which has a recess 17 open on its clamping surface 16, into which the sensor 18 of a dial gauge 13 attached to the screw clamp 14 projects. This measuring device is placed at any point between the weld seams 3, 4, 5 and 6 e.g. clamped at point 11 or 12.
Danach wird im Bereich der einen Quernaht 5 eine über ein Absperrorgan 9 und einen Schlauch 7 mit einer Druckgasquelle 8 verbundene Hohlnadel 10 in den von den Schweissnähten 3 bis 6 begrenzten Raum eingestochen und in diesen Druckgas eingebracht. Dadurch wölbt sich, wie aus Figur 2 ersichtlich, die eine Folie 1 auf und folgt in begrenztem Ausmass dem Verlauf der Wände der Ausnehmung 17. Then, in the area of the one transverse seam 5, a hollow needle 10 connected to a compressed gas source 8 via a shut-off device 9 and a hose 7 is inserted into the space delimited by the weld seams 3 to 6 and introduced into this compressed gas. As a result, as can be seen from FIG. 2, the film 1 bulges and follows the course of the walls of the recess 17 to a limited extent.
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661 124 661 124
Nach dem Absperren des von den Schweissnähten 3 bis 6 begrenzten Hohlraumes mittels des Absperrorgans 9 erfolgt eine Messung durch Ablesung der Messuhr 13. Nach einer vorbestimmten Zeitspanne erfolgt eine weitere Ablesung der Messuhr 13, wobei eine über einer bestimmten Toleranzgrenze liegende Verminderung des Abstandes der Aussen-seiten der beiden Folien eine unzulässige Undichtheit der Schweissnähte anzeigt. After the cavity delimited by the weld seams 3 to 6 has been shut off by means of the shut-off device 9, a measurement is carried out by reading the dial gauge 13. After a predetermined period of time, the dial gauge 13 is read again, with a reduction in the distance between the outside and a certain tolerance limit. side of the two foils indicates an impermissible leak in the weld seams.
Nach Abschluss der Prüfung wird die Nadel 10 herausgezogen und die kleine durch den Einstich bedingte Öffnung im Bereich der Quernaht 5 verschweisst. After the test is completed, the needle 10 is pulled out and the small opening caused by the puncture is welded in the area of the transverse seam 5.
Durch die Messeinrichtung gemäss Figur 2 ergibt sich der Vorteil, dass diese festgeklemmt werden kann und so sicher während der gesamten Prüfdauer an ihrem Platz verbleibt, s Auf diese Weise ist auch ein exakter Nachweis einer Änderung des Abstandes der Aussenseiten der Folien 1, 2 in dem von den Schweissnähten 3 bis 6 umgrenzten Bereich während der Prüfdauer möglich. Ausserdem ist auch die Anwendung einer solchen Messeinrichtung denkbar einfach und kann io auch von ungeschultem Personal durchgeführt werden. The advantage of the measuring device according to FIG. 2 is that it can be clamped and thus remains securely in place for the entire duration of the test. S This is also an exact proof of a change in the distance between the outer sides of the foils 1, 2 in which area bounded by welds 3 to 6 possible during the test period. In addition, the use of such a measuring device is extremely simple and can also be carried out by untrained personnel.
ß ß
1 Blatt Zeichnungen 1 sheet of drawings
Claims (3)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT106682A AT372787B (en) | 1982-03-17 | 1982-03-17 | METHOD FOR MEASURING THE TIGHTNESS OF MULTIPLE WELDING SEAMS |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CH661124A5 true CH661124A5 (en) | 1987-06-30 |
Family
ID=3505862
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CH1410/83A CH661124A5 (en) | 1982-03-17 | 1983-03-15 | METHOD FOR MEASURING THE TIGHTNESS OF MULTIPLE WELDING SEAMS. |
Country Status (3)
| Country | Link |
|---|---|
| AT (1) | AT372787B (en) |
| CH (1) | CH661124A5 (en) |
| DE (1) | DE3307945A1 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT399049B (en) * | 1990-06-27 | 1995-03-27 | Bauveg Baubetrieb Gmbh | CONNECTING PIPE |
| DE4021775A1 (en) * | 1990-07-07 | 1992-01-09 | Huels Troisdorf | METHOD FOR TESTING A WELDED CONNECTION |
| DE29620813U1 (en) * | 1996-11-29 | 1997-02-06 | Wegener Gmbh | Test device for checking the tightness of weld seams |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE7719086U1 (en) * | 1977-06-18 | 1977-12-01 | Hoechst Ag, 6000 Frankfurt | SPACE PRESSURE MEASURING DEVICE |
| DE2837997A1 (en) * | 1978-08-31 | 1980-03-13 | Manfred Ing Grad Gauchel | Gas tightness tester for plastics vessel - uses expanding vessel to move slide valve and register threshold pressure |
| GB2059381A (en) * | 1979-10-06 | 1981-04-23 | Danepak Ltd | Leak detecting of vacuum sealed packages |
-
1982
- 1982-03-17 AT AT106682A patent/AT372787B/en not_active IP Right Cessation
-
1983
- 1983-03-07 DE DE19833307945 patent/DE3307945A1/en not_active Ceased
- 1983-03-15 CH CH1410/83A patent/CH661124A5/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| DE3307945A1 (en) | 1983-09-22 |
| ATA106682A (en) | 1983-03-15 |
| AT372787B (en) | 1983-11-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PL | Patent ceased |