DE102014013522A1 - Method and device for carrying out an integrity test on a flexible test container - Google Patents

Abstract

In a method for carrying out an integrity test on a flexible test container (1), the test container (1) is arranged in a test container (5) which can be closed in a fluid-tight manner, a negative pressure is provided in the interior of the sealed test container (5), a test fluid is introduced into the test container (5 filled test vessel, detected in the interior of the test container (5) existing test fluid and before filling the test fluid in the test container (5) arranged test container (1) provided a negative pressure.

Description

The invention relates to a method and a device for carrying out an integrity test on a flexible test container.

Hermetically sealed flexible containers such. B. Plastic bags are often used especially in bioprocessing. In many applications, flexible containers are used to hold cell culture solutions, blood conserves, bioreactor solutions, etc. Especially in bioprocessing, sterilized containers are often used to keep their sterility during use.

In order to be able to recognize a damaged container which is thus unsuitable for sterile use, the flexible container can be subjected to a leak test and / or an integrity test before use. In this case, a flexible test container to be tested is filled with a test gas and arranged in a sealable test container. In the test container, a vacuum is generated. If the test container has a leak, the test gas escapes from the test container due to the pressure difference between the test container and the test container due to the leak and can be detected in the test container.

If no test gas is detected in the test container, the test container passes the leak test and / or integrity test. If test gas is detected in the test container, the test container is unsuitable for use as a sterile container.

The invention has for its object to improve the performance of an integrity test on a flexible test container.

The object is solved by the subject matters of the independent claims. The dependent claims relate to preferred embodiments.

• – der Testbehälter in einem fluiddicht verschließbaren Prüfbehälter angeordnet wird,
• – ein Unterdruck im Innenraum des verschlossenen Prüfbehälters bereitgestellt wird,
• – ein Prüffluid in den im Prüfbehälter angeordneten Testbehälter eingefüllt wird,
• – der Innenraum des Prüfbehälters auf Vorhandensein von Prüffluid überprüft wird und
• – vor dem Einfüllen des Prüffluids in dem im Prüfbehälter angeordneten Testbehälter ein Unterdruck bereitgestellt wird.

A first aspect relates to a method for performing an integrity test on a flexible test container, wherein

• - The test container is placed in a fluid-tight sealable test container,
• A negative pressure is provided in the interior of the sealed test container,
• A test fluid is introduced into the test container arranged in the test container,
• - the interior of the test container is checked for the presence of test fluid and
• - Before the filling of the test fluid in the test container arranged in the test container, a negative pressure is provided.

With the method, the integrity of the test container can be checked, in particular a leak of the test container can be detected. As a test container, a test container with flexible walls is used, for. B. a plastic bag. The test container can have an opening at at least one point, via which the test fluid can be introduced into the test container. For this purpose, the test container may have at its opening a coupling for coupling to a supply line.

To carry out the method, the test container is arranged in the test container which can be closed in a fluid-tight manner. The interior of the test container is larger than the test container in unfolded form, so that the test container can be completely introduced into the test container without wrinkling. Alternatively, the test container can be assisted with a supporting device permeable to the test fluid in the test container and thus the complete unfolding can be prevented. The test container can walls of a dimensionally stable material such. B. metal walls that withstand a high vacuum. The test container can be opened to receive the test container and then closed again fluid-tight. The test container may have suitable seals at its openable location.

After the test container is arranged in the interior of the test container, the test container is closed again and generates a negative pressure in the interior of the test container. The negative pressure refers to a pressure gradient between the interior of the test container and the test container filled with test fluid. During a test period, the pressure in the interior of the test container is less than the pressure in the test fluid-filled test container. The negative pressure in the test container may relate in particular to a negative pressure relative to the atmospheric pressure.

In particular, the negative pressure can be provided by means of a test container pump, which sucks air from the closed test container. The test container pump can be connected via lines to the interior of the test container. Thus, the negative pressure in the test container z. B. be provided by a vacuum, in particular by a high vacuum. The more pronounced the negative pressure is compared with the test container filled with test fluid, the more reliably a leak of the test container can be detected.

The negative pressure in the test container can z. B. be set to a value between 5E-2 mbar and 1E-1 mbar

The test fluid is filled into the test container while the test container is in the test container located. The test fluid is preferably introduced into the test container after the interior of the test container has been placed in negative pressure. The test fluid may be directed from a test fluid source via a feed line into the opening of the test container. The test fluid source itself can be arranged outside or inside the test container.

The term test fluid here refers to a test gas and / or a test liquid. The test fluid may in particular be designed as a test gas that does not occur or only in very small form in the normal air mixture. This avoids that a leak of the test container is erroneously suspected by the detection of residual air in the test container. As a test fluid can z. B. helium can be used.

The test container can be filled with the test fluid to a predetermined and / or predeterminable test pressure.

If the test container has a leak, a portion of the test fluid enters the interior of the test container due to the pressure difference between the interior of the test container and the test container filled with test fluid through the leak. The interior of the test container is checked for the presence of test fluid. In particular, it is checked whether test fluid has penetrated through a leak of the test container into the interior of the test container. Thus, it can be checked whether and / or how much a concentration of test fluid in the test container increases. In this review, in addition to the absolute determination of whether any test fluid is present in the test container, continue to the level of the concentration of test fluid in the interior of the test container z. B. be determined depending on the elapsed time.

If an increase in the concentration of test fluid in the interior of the test container is detected which exceeds a predetermined and / or predeterminable limit value, then the test container does not pass the integrity test. This z. B. a predetermined, low diffusion through the flexible walls of the test container may be allowed, which leads to a small increase in the concentration of test fluid in the interior of the test container. However, if the concentration of test fluid in the interior of the test container within a predetermined period of time exceeds a predeterminable and / or predetermined limit value, the test container is classified as defective. Depending on the evaluation method, the course of the concentration of test fluid in the test container can also be determined and compared with a target course of the concentration of test fluid expected with undamaged test containers.

Experiments have shown that it can sometimes lead to damage of the test container in carrying out such a leak test. In particular, when providing the negative pressure in the test container, the flexible test container can greatly expand. This can cause damage to the test container.

During the process, however, a vacuum is provided prior to charging the test fluid in the test container disposed in the test container. This avoids that the test container is damaged when providing the negative pressure in the test container. The negative pressure in the test container can essentially correspond to the height after the negative pressure in the test container. The negative pressure in the test container can be provided via a test container pump, which pumps off the interior of the test container via its test container opening. The negative pressure in the test container may refer to a negative pressure relative to the atmospheric pressure.

The negative pressure in the test container with respect to the atmospheric pressure may be at least half as strong as the negative pressure in the interior of the test container relative to the atmospheric pressure in order to already significantly reduce the risk of damage to the test container when carrying out the method.

Thus, the method reduces the rejection of test containers as test items. By setting high standards for the sterility of the test containers, the rejects can be relatively large, so a reduction of the scrap represents a significant financial advantage.

According to one embodiment, the negative pressure is provided in the test container before and / or while the negative pressure is provided in the interior of the test container. This avoids swelling of the test container during the provision of the negative pressure in the test container. In particular, the negative pressure in the test container can be provided at least partially simultaneously with the negative pressure in the test container, as a result of which the load on the test container is particularly greatly reduced. In other words, a negative pressure in the interior of the sealed test container and the test container arranged in the test container can be provided at the same time.

According to one embodiment, during the provision of the negative pressures in the test container and in the test container, the height of the negative pressure in the test container is adjusted to the level of the negative pressure in the test container. This z. B. both negative pressures are actively monitored and / or controlled, both negative pressures are generated by a common vacuum pump, and / or during of pumping open a connecting valve between the two interiors. In particular, in this case a compliance with a pressure difference upper limit between the pressure in the interior of the test container and the pressure in the interior of the test container can be provided and provided.

According to a development of this embodiment, during the provision of the negative pressures in the test container and in the test container, a pressure equalization takes place between the interior of the test container and the interior of the test container. This can be z. B. via an opening of a separating valve between the two said interiors. The pressure equalization avoids a damagingly high pressure difference between the two mentioned internal spaces.

The pressure balance between the interior of the test container and the interior of the test container can be done by a vote between a test container pump for pumping the interior of the sealed test container and a test container pump for pumping the interior of the test container. So z. B. during operation, at least one of the two pumps mentioned are controlled so that the negative pressures in the two interiors are matched. The activation of the at least one pump may include a throttling, temporary switching off, and / or an amplification of the pumping power.

Alternatively or additionally, the pressure compensation can take place by means of a separating valve. The separating valve is arranged so that it separates the interior of the test container from the interior of the test container. The isolation valve can be arranged in a corresponding connection line. The isolation valve is controllable and can be opened and closed.

According to one embodiment, a substantially equal negative pressure is provided in the test container and in the test container.

According to one embodiment, the negative pressure in the test container is provided via a feed line via which the test fluid is also filled into the test container. In this case, at least the supply line, which is subsequently arranged on the test container, used for two purposes. The supply line can be coupled to the opening of the test container and have a splitting to a test container pump for providing the negative pressure on the one hand and to a Prüffluidquelle for filling the test fluid on the other. The test container pump and / or the test fluid source can be arranged outside the test container. To control individually controllable valves can be provided for the individual line sections. By using the same supply line to the test container, the number of total required supply lines is kept as small as possible.

According to one embodiment, the interior of the test container is rinsed after test fluid has been detected in the test container. If a test object, ie a test container, is deficient, test fluid from the test container enters the interior of the test container during the test procedure. In order to avoid damage to the test container due to contamination with the test fluid, it is cleaned by rinsing after a test container that has not been tested properly. After testing an integrity test container, flushing is not essential and can be saved. Thus, the interior of the test container can be rinsed in particular only after each test in which a test container was classified as defective.

According to one embodiment, a background concentration of test fluid in the test container is adjusted. Under certain circumstances, the provision of the negative pressure in the test container can take a long time, in particular when outgassing occurs from the test container. In this case, the background leak rate can also fall sharply. Although this is generally more positive for performing the integrity test, it can alter the dynamic increase in the leak rate at the beginning of the measurement. Depending on the evaluation method of the integrity test, it may therefore be advantageous if the background leak rate at the beginning of the measurement is in a predefined range and / or window. If this predefined range should be undershot, z. B. test fluid are introduced into the test container. This actively adjusts the background concentration of test fluid in the test container prior to starting the measurement to verify the integrity of the test container.

A second aspect relates to a test device for carrying out an integrity test on a flexible test container, comprising a test container closable in a fluid-tight manner in which the test container can be arranged, a test container pump for pumping the interior of the sealed test container, a test fluid source from which a test fluid is arranged in the test container Test container can be filled, a test fluid detector for detecting test fluid in the interior of the test container and a pump port through which the interior of the test container arranged in the test container can be pumped.

The test fluid source may be formed as a Prüfluluidbehälter having a supply of Püffluid, which is fillable via a supply line in the test container. The test fluid source can be arranged in particular outside the test container and be connected only via a supply line through a wall of the test container with the interior of the test container. In the test container, an opening of the test container can be coupled to a supply connection of this supply line.

The pump connection can be arranged in the interior and / or exterior of the test container and designed and provided to be connected to an opening of the test container. For this purpose, the pumping port can have a suitable coupling. About the pumping port, the interior of the test container with a test container pump can be connected via which a negative pressure in the interior of the test container is provided. Preferably, the test container pump is arranged outside of the test container, whereby a compact dimensioning of the test container is made possible.

The pump connection can be designed as a supply connection, so that the interior of the test container can both be pumped off via a dual-functional connection and / or a dual-functional supply line, and can later be filled with the test fluid. The test device may have one or more valves via which a supply line from the test container pump to the interior of the test container, a supply line from the test container pump to the interior of the test container, a supply line from the test fluid source to the interior of the test container, etc. are controllable and / or controllable.

The test device may further include a controller for driving the valves and / or pumps of the test device. The controller may include a computer processor.

In particular, the test device makes it possible to provide a negative pressure in the test container and in the test container at the same time.

In one embodiment, the test device has a separating valve between the interior of the test container and the interior of the test container. Pressure equalization can take place via the separating valve, which reduces load on the test container when the negative pressure is formed to a different degree.

A third aspect relates to the use of the test device according to the second aspect for carrying out an integrity test on a flexible test container according to the method according to the first aspect.

The invention will be explained in more detail with reference to embodiments shown in FIGS. Individual aspects of the embodiments illustrated in the figures may be combined with other embodiments. Show it:

1 a schematic representation of a first test device for performing an integrity test on a flexible test container;

2 a schematic representation of a second test device for performing an integrity test on a flexible test container;

3 a flow chart of a first method for performing an integrity test on a flexible test container;

4 a flow chart of a second method for performing an integrity test on a flexible test container and

5 a graph of a time course of the expected concentrations of test fluid in the test container of dense and defective tested test containers.

1 shows a schematic representation of a first test device 10 to perform an integrity test on a flexible test container 1 ,

The test device 10 has a test container 5 on, which is designed openable and fluid-tight closable. The test container 5 can be dimensionally stable and z. B. metal and / or plastic walls. The test container 5 is designed and intended to withstand a vacuum, in particular a vacuum, in its interior. A (in 1 not shown) opening of the test container 5 may have seals to ensure a fluid-tight seal.

In the test container 5 is the flexible test container 1 removably arranged. The test container 5 can provide mechanical support, especially one on the test container 1 matched bearing surface, on which the test container 1 essentially wrinkle-free can be placed. The mechanical support may be formed of a porous material, whereby blocking of leakage of the test container by the support can be prevented.

The flexible test container to be tested 1 may be formed as a single container, or as an arrangement of a plurality of containers, the z. B. are interconnected by hoses. The test container 1 is at least partially flexible.

The test container 1 has an opening which is coupled to a test container supply line L1. About the test container lead L1 can the interior of the test container 1 Be supplied with fluids or pumped out of it. The Test container feed line L1 passes through an opening in the test container wall of the test container 5 in the outer space of the test container 5 ,

The interior of the test container 5 is connected to two supply lines, namely to a Prüfbehälterzuleitung L2 and to a vent line L3. About the Prüfbehälterzuleitung L2 and a Prüfbehälterpumpventil V2 is the interior of the test container 5 with a test container pump 4 connectable. Furthermore, the interior of the test container 5 via the test container feed line L2 and a detector valve V1 with a test fluid detector 2 connectable. The test fluid detector suitable for the test fluid used 2 serves to detect the from the test container 1 leaking test fluid in case of leakage in the test container 1 ,

The test fluid detector 2 is designed and provided, the concentration of a predetermined test fluid in the interior of the test container 5 to detect.

The test container pump 4 can be designed as a high vacuum pump, which is the interior of the test container 5 can evacuate to a high vacuum with a maximum pressure of 10 ^-3 mbar, z. B. at a very low background leakage rate in the test container 5 provide. A low background leak rate allows fast measurement. The smaller the background leak rate in the test container 5 is formed, the more obvious is the dynamic behavior of the leak rate through the test container 1 in case of a defect of the test container 1 pronounced at the beginning of the measurement. Such a dynamic increase in the concentration of test fluid in the interior of the test container 5 , in particular before a permeation through side walls of the test container 1 Occurs, may be to detect a leak in the test container 1 be evaluated.

In the test container feed line L1, a test container filter F1 is arranged, which is designed as a particle filter and inhibits the passage of particles through the test container feed line L1.

About the Testbehälterzuleitung L1 and a test container pump valve V4 is the interior of the test container 1 with a test container pump 6 connectable, the negative pressure, in particular a vacuum, in the test container 1 can generate.

The test container pump 6 is designed and intended to coincide with the evacuation of the test container 5 the evacuation of the test container 1 to cause, what an overpressure in the test container 1 and thus damage can be avoided. At the end of the test, the test container pump 6 used to return the test fluid from the test container 1 to evacuate.

Furthermore, the interior of the test container 1 via the test container feed line L1 and a test fluid valve V3 with a test fluid source 3 connectable. This way is the test container 1 filled with a test fluid, in particular a test gas such as a noble gas. There is a supply of test fluid in the test fluid source 3 arranged. The test fluid source 3 can be designed as a reservoir. The test fluid in the test fluid source 3 may be biased under a predetermined and / or predeterminable test pressure to by relaxing the test fluid in the test container 1 to produce the test print almost immediately. This is particularly advantageous when using test gases such. As helium, which have very small atomic or molecular sizes and therefore very fast through the wall of the test container 1 permeate. The main measurement can therefore be started as quickly as possible.

The interior of the test container 5 can be vented via the vent line L3. The venting can be controlled via a test vessel venting valve V5 arranged in the venting line L3. In the vent line, a test container filter F2 is further arranged, which may be formed as a particle filter.

Via a test container ventilation valve V6 and the test container supply line L1 is also the interior of the test container 1 vented.

In the 1 shown test device 10 is used to perform an integrity test on the flexible test container 1 , The test container 1 is exchangeable and not part of the test device 10 , The test device 10 Rather, it can be used repeatedly to check a plurality of different flexible test containers.

The sequence of the corresponding test procedure is shown in a schematic flowchart in FIG 3 shown. In this flowchart, individual method steps of a method for carrying out an integrity test on a flexible test container are given, which are shown in the flow chart of FIG 3 to control the in 1 shown test device 10 are shown.

With method step A, the integrity test begins. At the beginning all pumps of the test device, in particular the test container pump, run 4 and the test container pump 6 , Furthermore, all valves of the test device are at the beginning of the process 10 closed.

In step B, both the test container 5 as well as the test container 1 emptied, more precisely, in these two containers each one Vacuum provided to the atmospheric pressure, z. B. a high vacuum. This is done by opening the Prüfbehälterpumpventils V2 and the Testbehälterpumpventils V4, whereby the two pumps 4 and 6 be switched. The evacuation of the test container 1 takes place parallel to the evacuation of the test container 5 ,

If a predetermined and / or predeterminable reduced pressure is reached as the vacuum pressure p _vacuum in the test container, in method step C the test fluid detector 2 switched on the detector valve V1. This occurs when the vacuum pressure in the test container 5 is less than a predetermined and / or predeterminable first pressure limit Limit1_p _vacuum . p _vacuum designates the pressure in the test container 5 , In method step C, a recording of a background leak rate begins by pre-measuring the concentration of test fluid in the interior of the test container 5 , The first pressure limit Limit1_p _vacuum may depend on the working pressure of the test fluid detector 2 be predetermined. The measurement of the concentration of test fluid in the test container 5 begins as a pre-measurement of the background leak rate, also referred to as background concentration, even before the actual main measurement.

In method step D, a compliance with the starting conditions for the main measurement is checked. It can be checked in particular whether the predetermined negative pressure, in particular a predetermined high vacuum, is reached in the test container, ie whether p _vacuum ≤ Limit2_p _vacuum applies, wherein Limit2_p _vacuum defines a second pressure limit as the minimum allowable limit for the pressure in the interior of the test container. Furthermore, it can be checked whether a maximum allowable background leak rate is undercut, namely whether LeakRate ≤ Limit1_LeakRate applies, whereby LeakRate the actually measured background leak rate in the test container 5 and Limit1_LeakRate a first allowable leakage limit for the background leak rate.

If all starting conditions are met, in method step F, the valves V2 and V4 are closed in order to enable the start of the leak test with the main measurement.

During process step G, the test fluid enters the test container 1 filled. This is the test container 1 filled with test fluid by opening the test container valve V3 and brought to a predetermined and / or predeterminable test pressure p_test. This can be done in a fraction of a second, eg. B. by a suitable ratio of pressure to volume between the test container 1 and the preloaded test fluid source 3 , This type of filling, that is to say a pressure filling with pretensioned puffing fluid from the test fluid source, enables a very rapid start of the main measurement before the permeation occurs. The increase in background leakage in the event of a defect on the test container 1 occurs almost immediately, the increase by permeation a little time-delayed. This delay depends on the selected test fluid and the barrier behavior of the test vessel wall.

With the method step H, the actual main measurement begins. In method step H, an evaluation of the test container takes place 1 , After a predetermined and / or predeterminable test time TestTime without exceeding a third leakage limit of the test container 1 rated as tight (method step H2). Will the third leak limit Limit3_LeakRate in the test container 5 exceeded, then the test container 1 rated as defective (step H1). In this case, the method can already be stopped before the end of the test time to increased contamination of the test container 5 to avoid.

In method step I, the test fluid detector 2 disconnected and the main measurement stopped. The test fluid detector 2 is decoupled by closing the detector valve V3, which stops the measurement.

Subsequently, in step J, the test fluid is evacuated. In the process, the test fluid is removed from the test container by opening the test container pump valve V4 1 evacuated.

Is the evacuation a predetermined and / or predeterminable _test container pressure p _test in the _test container 1 undershot (and the condition p _test ≤ Limit1_p _test met, wherein Limit1_p _test defines a pressure limit of the _test container pressure) and thus evacuated almost the entire test gas, carried out in step K, a ventilation of the test device 10 , In the process, the test container pump valve V4 is closed and the complete system of the test apparatus, ie the test container circuit and the test container circuit, is vented to atmospheric pressure by opening the valves V5 and V6.

After the test vessel pressure p _{vacuum has reached} the atmospheric pressure p _ath , the valves V5 and V6 are closed and the test device 10 in method step M is set in the starting position.

2 shows a schematic representation of a second test device 20 to perform an integrity test on a flexible test container 1 ,

The second test device 20 has all the components of the first test device 10 on. The corresponding components of the two test devices have the same reference numerals.

The second test device 20 has some additional components, the different and independent additional functions of the second test device 20 in comparison with the first test device 10 provide.

A first additional function is provided by a flushing fluid source 7 provided. In the flushing fluid source 7 a pre-stressed flushing fluid is arranged, with which a contamination of the test container due to permeation or defect can be rinsed off by the test fluid.

From the flushing fluid source 7 is the flushing fluid via a purge valve V9 and a purge line L4 in the interior of the test container 5 recoverable. This allows the components flushing fluid source 7 , Purge valve V9 and purge line L4 a purge function as the first additional function. The flushing takes place via the flushing line V4, through the test container 2 , wherein the existing test fluid and the flushing fluid via the lines L2 and L3 through the open vent valves V5 and V6 and the isolation valve V7 from the test container 2 be rinsed.

As an alternative to the connection via the purge line L4, the purge fluid source could 7 via the purge valve V9 also be coupled to another line, z. B. with the Prüfbehälterzuleitung L2. The existing test fluid and the flushing fluid would in this embodiment via the line L3 through the open Prüfbehälterbelüftungsventile V5 from the test container 2 be rinsed. In this case, the isolation valve V7 may be closed to a defined rinse cycle through the test container 2 to provide.

A second additional function of the second test device 20 is by means of an additional connection of the test fluid source 3 via a test fluid inlet valve V8 into the interior of the test container 5 provided. In the in 2 As shown embodiment, a coupling via the purge line L4, alternatively, the coupling could also be done via one of the other leads or another additional supply line.

The second additional function makes it possible to set a background concentration (and thus background leak rate) of test fluid in the interior of the test container 5 what u. U. can accelerate the beginning of the test process.

A connection which can be activated via an isolating valve V7 between the test container feed line L1 and the test container feed line L2 makes it possible to equalize the pressure between the test container 1 and the test container 5 as a third additional function.

In the 2 shown test device 20 is used to repeat an integrity test on a flexible, replaceable test container 1 , The sequence of the corresponding test method for controlling the second test device 20 is in a schematic flowchart in 4 shown. The individual method steps for controlling the second test device 20 are essentially the same as in 3 shown method steps. The three additional functions of the second test device 20 However, allow some additional process steps and the extension of some of the process steps described above.

In the following, only the additional or modified method steps will be described in comparison with the method steps described above. The modified method steps are characterized by a dash (such as B 'in comparison to B), the additional method steps are characterized by a new letter (here method steps E and L).

Thus, in process step B 'when emptying the test container 5 and the test container 1 additionally via the separating valve V7, the test container circuit and the test container circuit short closed to an overpressure in the test container 1 and thus to avoid possible damage. By opening the separating valve V7 thus takes place a pressure equalization between the interior of the test container 1 and the interior of the test container 5 , Thus, a substantially high negative pressure is provided in the two containers substantially.

In step C ', the isolation valve V7 is additionally closed, whereby the two circles are separated from each other.

In method step D ', that is to say when checking the starting conditions, a more coordinated reaction to different measurement results takes place during the pre-measurement, that is to say before the start of the main measurement. Under certain circumstances, it may happen that the evacuation to the negative pressure in the test container 5 , in particular to a high vacuum, takes a very long time (eg due to outgassing from the test container 1 ). In this case, the background leak rate in the test container can also be 5 fall very much. Although this is basically not negative for the measurement, it also alters the dynamic increase in the background leak rate at the beginning of the main measurement. Depending on the method of evaluation, it may thus be advantageous for the background leak rate to be at the start of the main measurement in a defined window. If this window is undershot, test fluid may be added to the test container 5 be introduced.

Thus, when the background leak rate LeakRate becomes a second limit2LeakRate limit falls below, a step E interposed. In method step E, the background concentration of test fluid in the test container 5 elevated. For this purpose, the test fluid inlet valve V8 is opened until the start condition LeakRate ≥ Limit2 LeakRate is fulfilled.

In step F 'in addition, the isolation valve V7 and possibly the Prüffluideinlassventil V8 is closed to provide a readiness for the main measurement and leak test.

The method steps G, H, I and J correspond to the method steps described above.

In the aeration in step K ', however, the isolation valve V7 may additionally be opened to allow more thorough and faster ventilation.

In the case of a negative test piece evaluation in method step H1 and the associated contamination of the test container 5 an additional rinsing is carried out in method step L. In this case, the entire test container circuit is rinsed via the opened valves V5, V7 and V6 and the lines L2, L4 and L3 by opening the rinsing valve V9.

Accordingly, when the method is terminated in method step M ', additionally the valves V7 and V9 are closed.

5 shows in a diagram several time courses of the expected concentration of test fluid in the test container for four different test containers.

A first time course 1-0 shows the expected concentration ("Leak rate in mbar · l per s") of helium as the test gas of an undamaged test container. The main measurement begins after about 4 seconds, during which the concentration of the background leak rate below 2 · 10 ^-7 mbar · l / s to about 6 · 10 ^-6 mbar · l / s after about 12 seconds (corresponds to max_TestTime) slowly increases.

A second time course 1-2 shows the expected concentration of helium as the test gas of a test container with a leak of about 2 μm in diameter. In this case, the concentration already increases before the actual main measurement (ie, before method step H, during process step G) via the background leak rate to about 4 × 10 ^-7 mbar · l / s after about 4 seconds. During the test time during the main measurement, the concentration increases to approx. 1 · 10 ^-5 mbar · l / s after approx. 12 seconds.

A third time course 1-5 shows the expected concentration of helium as the test gas of a test container with a leak of approximately 5 μm in diameter. Here, too, the concentration rises above the background leak rate to about 2.3 · 10 ^-6 mbar · l / s after about 4 seconds, even before the start of the main measurement. During the test period, the concentration increases to approx. 2.3 · 10 ^-5 mbar · l / s after approx. 12 seconds.

A fourth time course 1-7 shows the expected concentration of helium as the test gas of a test container with a leak of approximately 7 μm in diameter. The concentration above the background leak rate increases to about 8 · 10 ^-6 mbar · l / s after approx. 4 seconds before the main measurement starts. During the test period, the concentration increases to approx. 5 · 10 ^-5 mbar · l / s after approx. 12 seconds.

The main measurement could also begin at time t = 0 s. The range between t = 4 s and t = 12 s is in the embodiment shown a predetermined test time range, during which a reliable differentiation between defective and defect-free test containers is possible.

Depending on the evaluation method, in the event of a faulty test container as the test item, the measurement may be terminated even before the end of the full test time, eg. B. if in addition to the absolute value and a course of the concentration is detected.

LIST OF REFERENCE NUMBERS

1

test container

2

Prüffluiddetektor

3

Prüffluidquelle

4

Prüfbehälterpumpe

5

test container

6

Test container pump

7

irrigation fluid

10

first test device

20

second test device

F1

Test tank filter

F2

Prüfbehälterfilter

L1

Test container supply

L2

Prüfbehälterzuleitung

L3

vent line

L4

flushing line

V1

detector valve

V2

Prüfbehälterpumpenventil

V3

Prüffluidventil

V4

Test tank pump valve

V5

Prüfbehälterbelüftungsventil

V6

Test tank ventilation valve

V7

isolation valve

V8

Prüffluideinlassventil

V9

flush valve

p _test

Test tank pressure

p _vacuum

Prüfbehälterdruck

Claims (11)

Method for carrying out an integrity test on a flexible test container ( 1 ), wherein - the test container ( 1 ) in a fluid-tight sealable test container ( 5 ) is arranged, - a negative pressure in the interior of the sealed test container ( 5 ), - a test fluid in the test container ( 5 ) arranged test containers ( 1 ), - in the interior of the test container ( 5 ) existing test fluid is detected and - before filling the test fluid in the test container ( 5 ) arranged test containers ( 1 ) A negative pressure is provided. Method according to claim 1, wherein the negative pressure in the test container ( 1 ) is provided before and / or during the negative pressure in the interior of the test container ( 5 ) provided. Method according to claim 1 or 2, wherein during the provision of the negative pressures in the test container ( 1 ) and in the test container ( 5 ) the level of negative pressure in the test container ( 1 ) to the level of negative pressure in the test container ( 5 ). Method according to claim 3, wherein during the provision of the negative pressures in the test container ( 1 ) and in the test container ( 5 ) a pressure equalization between the interior of the test container ( 1 ) and the interior of the test container ( 5 ) he follows. Method according to claim 4, wherein the pressure equalization between the interior of the test container ( 1 ) and the interior of the test container ( 5 ) by - a vote between a test container pump ( 4 ) for pumping the interior of the sealed test container ( 5 ) and a test container pump ( 6 ) for pumping the interior of the test container ( 1 ) and / or - by means of a separating valve (V7). Method according to one of the preceding claims, wherein the negative pressure in the test container ( 1 ) is provided via a supply line (L1) via which the test fluid is also introduced into the test container (L1). 1 ) is filled. Method according to one of the preceding claims, wherein the interior of the test container ( 5 ) is rinsed after in the test container ( 5 ) Test fluid was detected. Method according to one of the preceding claims, wherein a background concentration of test fluid in the test container ( 5 ) is set. Test device ( 10 ; 20 ) to perform an integrity test on a flexible test container ( 1 ), with - a fluid-tight sealable test container ( 5 ), in which the test container ( 1 ), - a test container pump ( 4 ) for pumping the interior of the sealed test container ( 5 ), - a test fluid source ( 3 ) from which a test fluid is placed in the test container ( 5 ) arranged test containers ( 1 ), - a test fluid detector ( 2 ) for detecting test fluid in the interior of the test container ( 5 ) and - a pump connection, via which the interior of the in the test container ( 5 ) arranged test container ( 1 ) is pumpable. Test device ( 10 ; 20 ) according to claim 9 with a separating valve (V7) between the interior of the test container ( 1 ) and the interior of the test container ( 5 ). Use of the test device ( 10 ; 20 ) according to claim 9 or 10 for carrying out an integrity test on a flexible test container ( 1 ) according to the method of any one of claims 1 to 8.

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