Patent Application
20050188774
The present invention relates to a sampling device comprising a sampling container for reception of a sample volume and a connecting piece adapted to be connected to a fitting mounted on a vessel or pipe of a processing installation or the like, the connecting piece having a sample passage which is provided with a stationary valve part and a corresponding valve member which is displaceable between a closed position, in which it abuts the stationary valve part and closes the sample passage, and an open position, in which the sample passage is open, whereby the valve member is spring-loaded towards its closed position and adapted to be automatically displaced to its open position upon connection of the connecting piece with the fitting.
EP 0141. 940 codesponding to U.S. Pat. No. 4,580,452 discloses a sampling container being connected through a pipe to a manually operated sampling valve which way be screwed into a fitting mounted on a conduit forming part of a chemical plant installation. The fitting is also provided with a manually operated valve in order to close the outlet from the conduit when the sampling valve is not connected to the fitting. To take a sample, firstly the sampling valve must be screwed into the fitting, the two valves must be opened and subsequently closed, and the sampling valve must be disconnected from the fitting. Obviously, this procedure is time-consuming, and furthermore there is a risk of forgetting to close one of the valves after having taken a sample, whereby possibly hazardous product could escape from the sampling system. Additionally, the configuration of the sampling container and its connected valve is awkward to handle and susceptible to damages if dropped, which may result in product spillage. Furthermore, the device is suitable for the sampling of fluids only, as products such as powder or granules would clog up the passages through the valves and the pipe.
DE 40 34 700 describes a dual-valve system for the taking of a fluid sample from a pipe system. A first valve member in the form of a truncated cone is arranged in a pipe rotatably about an axis perpendicular to the direction of flow in the pipe and has a through passage in-line with the pipe opening when set to its open position. In this open position, a sample may be taken from the pipe through a second valve arranged in a connection piece inserted in the lower side of the truncated cone. After having taken a sample, both valves are closed, and the internal product-contaminated surfaces which are situated between the two closed valves are cleaned by means of a spray device. However, this procedure is most cumbersome and time-consuming. Furthermore, the system also has the disadvantage that the second valve must be closed manually in order to prevent spillage of the product sampled. The sampling container protrudes radially from the second valve and makes the device awkward in use.
DE 43 01 174 discloses a sampling valve having a semi-cylindrical valve member arranged rotatably in a bore extending tangentially to the inner surface of a pipe wall. An external sampling container is screwed into a fitting which is mounted on the outside of the pipe wall and is in fluid connection with the bore through a passage. When the valve member is in its open position, a fluid may pass from the pipe to the sampling container. After removing the sampling container from the fitting, the container is open to the surroundings and consequently product may be spilled.
DE 197 35 586 shows a sampling valve having an outlet opening through the wall of a pipe and a corresponding valve member which by means of a spindle is manually operable from the outside of the pipe. A sampling container for the reception of a fluid may be held under the outlet opening when the valve is opened.
U.S. Pat. No. 4,689,306 describes a device for sterile sampling from a fermenter. The device comprises a sample collector having a normally closed valve mounted on its neck inside a valve housing and a sampler having a normally closed valve, also located in a valve housing, and being positioned on the fermenter. To take a sample, the neck of the sample collector is positioned against the sampler, whereby rods of said valves press against each other, thereby opening the valves and allowing product to enter the sample collector through the valve housings.
U.S. Pat. No. 4,699,356 describes a fluid sampling valve, within the body of which there is a central bore interconnecting a sample end and a vessel end, thereby allowing fluid communication through the valve. Within the central bore, there is a cylindrical valve stem having at one end proximate to the sample end a conically-faced head being urged toward a sealing ring in the sample end by a spring, thereby closing the central bore against the surroundings. By inserting a hollow cylindrical sampling probe through said sealing ring, the conically-faced valve head is lifted from the sealing ring, and fluid communication is provided through a hole in the wall of the hollow sampling probe to the fluid sample container.
U.S. Pat. No. 4,150,575 describes a fluid sampling system comprising a fluid coupling and a sampler in which the coupling is included. The fluid coupling comprises a coupling valve that includes an annular valve seat axially slidable within a valve housing of the fluid coupling. The seat has a conical central opening, within which a valve closure member is slidable and includes a tapered head shaped and dimensioned to fit tightly within the seat. In order to take a sample, the coupling is connected to a coupling receiver comprising a receiver housing and a plug which form a fluid tight seal in a manner similar to that of the coupling valve. Upon connection, the valves open, and fluid can then enter a cross-bore in the closure member of the valve leading to a small diameter axial bore by which it exits from the opposite end of the coupling.
The sampling device according to the invention is characterized in that the stationary valve part or the valve member is formed as a conical face forming part of a wall surrounding the inside volume of the sampling container, and in that the other one of said stationary valve part and said valve member has the form of a truncated cone carried by a spindle extending coaxially through the inside volume of the sampling container.
Because the integrated design ensures a short and unimpeded path for the product to be sampled, the sampling device according to the present invention is very suitable for the sampling of powders, granules and the like, as well as any type of fluid or flowable product.
The sampling container will always be automatically closed by means of the valve member upon disconnection of the container from the fitting, and product spillage through the connection piece may be hindered, even if the container should be dropped. Furthermore, the integrated design of the stationary valve part and the valve member in the sampling container provides for a more robust construction and a device which is easier and therefore safer to handle. Consequently, also the risk of dropping the device is reduced.
The displaceable valve member has a conical sealing surface corresponding to a conical sealing surface on the stationary valve part. This ensures a good sealing effect.
In a simple and therefore reliable embodiment, the connecting piece is adapted to be displaced in a longitudinal direction of the container during at least part of the operation of connecting it to the fitting, and the displaceable valve member is adapted to abut an edge of the fitting during at least part of said displacement. The valve member will then be displaced in the sampling container to its open position as a result of the displacement of the connecting piece in the direction against the fitting.
In a preferred embodiment, the connecting piece is adapted to be screwed onto the fitting. This ensures a strong connection between the connecting piece and the fitting. The device may in this way be designed explosion proof, for instance in order to be able to withstand an internal pressure of 10 bar
In an advantageous embodiment, the sampling container comprises an outer container and an inner container, the inner container is arranged displaceably in a longitudinal direction of the outer container, the outer container is at a first end formed integrally with the connecting piece and is at a second end provided with a bottom, the inner container is at a first end formed integrally with an annular sealing surface, thereby forming the displaceable valve member, and has at a second end a bottom in which a spindle passage is provided, a spindle has a first end which is provided with the stationary valve part and a second end which is fixed to the bottom of the outer container, and the spindle passage is arranged tightly around and displaceably along the spindle. By the provision of two containers arranged one inside the other, an even more robust construction is achieved, especially in terms of the ability to withstand a high internal pressure, but also considering the risk of dropping the container. Furthermore, the device is simple to manufacture because very few components are required.
In an embodiment, the outer length of the outer container is between 100 mm and 300 mm, the outer diameter of the outer container is between ½ and ⅔ of the outer length of the outer container, and the smallest diameter of the annular sealing surface of the inner container is between ¼ and ⅔ of the outer diameter of the outer container.
In an advantageous embodiment, the outer container and the inner container are formed from Plexiglass (registered trademark), glass, tempered glass or the like, and the stationary valve part is formed from polytetrafluoroethylene or the like. This configuration allows visual inspection of the product sample through the Plexiglass or glass, and a good sealing effect is obtained between Plexiglass or glass and polytetrafluoroethylene.
In a further embodiment, the sampling device comprises a fitting mating the connecting piece and having an installation end adapted to be installed onto the vessel or pipe of said processing installation or the like, and the fitting has a tubular part provided with an inner shielding member adapted to shield the stationary valve part in the connected state of the connecting piece and the fitting. Thereby the outward surface of the stationary valve part is shielded against the sample product during taking of the sample and consequently this surface will be free from product after removal of the sampling container from the fitting. This may be an advantage especially in case of hazardous products.
Further, the product flow may be guided and thereby facilitated by the shielding member.
In a further embodiment, the tubular part of the fitting is provided with a covering member adapted to cover the displaceable valve member in the connected state of the connecting piece and the fitting. Thereby also the displaceable valve member will be free from product after removal of the sampling container from the fitting and the cleanliness of the device is further improved.
In a further embodiment, the shielding member is adapted to seal against the covering member in the disconnected state of the connecting piece and the fitting. This prevents product from leaking from the fitting after removal of the sampling container from the fitting. Especially in case of toxic products, this may be an advantage.
In a further embodiment, a circumferential contour of the shielding member fits a circumferential contour of the stationary valve part, the shielding member is adapted to be displaced with the stationary valve part against a spring-load during at least part of the operation of connecting the connecting piece to the fitting, a circumferential contour of the covering member fits a circumferential contour of the displaceable valve member, the covering member is fixedly mounted in the fitting, the circumferential contour of the shielding member fits the circumferential contour of the covering member, and the circumferential contour of the stationary valve part fits the circumferential contour of the displaceable valve member. Thereby a product sample may be taken out from a processing installation in a fully contained way, so that, after disconnection of the sampling container from the fitting, substantially no product will leak to the surroundings of the fitting and the sampling container. In this way, the operator will practically not be exposed to the product sampled.
The shielding member may have a conical sealing surface corresponding to a conical sealing surface on the covering member. This ensures improved sealing effect.
In a further embodiment, the shielding member is spring-loaded against the covering member by means of a spring located in a tube element in which a spindle of the shielding member is guided, the tube element is guided axially in the tubular part of the fitting, and the tube element is fixed in a plate adapted to abut an edge of a flange on the vessel or pipe of the processing installation or the like, in the mounted state of the fitting on said flange. Thereby the shielding member will be automatically spring-loaded against the covering member upon installation of the fitting on the flange.
In an advantageous embodiment, the fitting comprises a shut-off valve. This may especially be advantageous if no shielding and covering members are provided in the fitting, or if both high and low pressures may occur in the vessel or pipe of the processing installation. In the latter case the shut-off valve ensures that the shielding member is not lifted from the covering member as a result of a pressure difference between the internal of the processing system and the exterior surroundings.
In a further embodiment, the sampling device comprises a nozzle adapted to be connected to the fitting and having an internal projection adapted to keep the shielding member displaced against the spring-load in the connected state of the nozzle to the fitting, and the nozzle has a tube connection for supply or discharge of cleaning or washing fluid. Thereby the interior of the fitting may be cleaned or washed after the taking of a sample.
The present invention also relates to a sampling method for taking a sample of a product from a processing installation or the like, comprising the steps of connecting a connecting piece of a sampling device to a fitting mounted on a vessel or pipe of the processing installation or the like, displacing a valve member in a sample passage of the connecting piece from a closed position, in which it closes the sample passage, to an open position, in which the sample passage is open, allowing product to pass from the processing installation or the like, through the sample passage, and into a sampling container of the sampling device, displacing the valve member from its open position to its closed position, and disconnecting the connecting piece from the fitting, whereby the valve member is displaced from its closed position to its open position against a spring-load, and whereby the valve member is automatically displaced to its open position upon connection of the connecting piece with the fitting.
The sampling method is characterized by that, in the open position of the valve member, the product passes trough a conical annular passage formed between a conical face forming part of a wall surrounding the inside volume of the sampling container and a truncated cone carried by a spindle extending coaxially through the inside volume of the sampling container. Thereby the above-mentioned advantages are obtained.
In a further embodiment of the sampling method, the valve member is displaced to its open position by means of a covering member fixedly mounted in the fitting and abutting the valve member during at least part of the operation of connecting the connecting piece to the fitting, whereby a circumferential contour of the covering member fits a circumferential contour of the valve member, by that a shielding member mounted displaceably in the fitting abuts the stationary valve part, whereby a circumferential contour of the shielding member fits a circumferential contour of the stationary valve part, and whereby the shielding member is displaced against a spring-load during at least part of the operation of connecting the connecting piece to the fitting, and by that, after disconnecting the connecting piece from the fitting, the circumferential contour of the shielding member fits the circumferential contour of the covering member, and the circumferential contour of the stationary valve part fits the circumferential contour of the displaceable valve member. Thereby a sample may be taken out in a fully contained way as explained above.
In a further embodiment of the sampling method, a shut-off valve of the fitting is opened and subsequently closed in the fully connected state of the connecting piece and the fitting in order to allow the product to pass through the fitting. Thereby the above-mentioned advantages are obtained.
In a further embodiment of the sampling method, in the disconnected state of the connecting piece and the fitting, a nozzle is connected to the fitting, whereby an internal projection in the nozzle keeps the shielding member displaced against the spring-load in the connected state of the nozzle to the fitting and a cleaning or washing fluid is supplied to or discharged from the fitting through the nozzle. Thereby the above-mentioned advantages are obtained.
The invention will be described in more detail below by means of examples of embodiments with reference to the schematic drawing, in which
The sampling device 1 and the method of sampling according to the invention may be used in all industries, e.g. such as pharmaceutical, biotechnological and chemical, for all kinds of processing equipment or storage containers as well as pipe systems, and for all kinds of products, e.g. such as powders, granules, liquid products and gaseous products, as well as any possible combination of products. For powders and granules, the processing installation to take samples from may e.g. be fluid bed equipment, granulation equipment, agglomeration equipment, coating equipment, layering equipment, extrusion equipment, spray drying equipment, packaging equipment etc. Furthermore, heavy, sticky or viscous products or products having limited flow capabilities may be sampled by means of the device and the sampling method according to the invention.
At a first end, the outer container 5 is formed integrally with a connecting piece 7 in the form of an internal thread 8 which in
At a first end, the inner container 6 is formed integrally with a displaceable valve member 14 in the form of a conical sealing surface 15 facing away from the interior of the sampling container 4 and corresponding to the conical sealing surface 13 of the stationary valve part 12. At a second end, the inner container 6 has a bottom 16 in which is formed a concentric spindle passage 17 sealed displaceably against the spindle 11 by means of an O-ring 18.
Between the bottom 16 of the inner container 6 and the bottom 10 of the outer container 5 is arranged a compression spring 19 around the spindle 11, thereby spring-loading the inner container 6 with its integral valve member 14 towards a closed position of the displaceable valve member 14, in which position the conical sealing surface 15 of the valve member 14 abuts the conical sealing surface 13 of the stationary valve part 12, as shown in
In the connected state of the connecting piece 7 to the fitting 2, as shown in
In order to take a sample from the vessel 3, the closed sampling container 4 shown in
In a typical execution, the outer container 5 has an outer length of approximately 130 mm, an outer diameter of approximately 75 mm and a wall thickness of approximately 10 mm and the inner container 6 has an inner diameter of approximately 40 mm and an inner length between its bottom 16 and its annular sealing surface 15 of approximately 65 mm. In this execution, the length of the internal thread 8 of the outer container 5 is approximately 18 mm and the outer length of the fitting 2 is approximately 53 mm. The diameter of the circumferential contour 32 of the covering member 31 fitting the circumferential contour 29 of the shielding member 25 is approximately 34 mm. In another typical execution, said dimensions have been multiplied by two. The dimensions and the materials may also typically be chosen so as to ensure that the device is explosion proof for a required pressure.
The embodiments of the sampling device 1 shown in FIGS. 1 to 3 and 6 to 8 are especially suitable if the pressure in the vessel or pipe of the processing installation to be sampled from is below atmospheric, as substantially the same pressure will be present in the sampling container 4 after having taken the sample. Consequently, the pressure difference between the surroundings and the internal of the sampling container 4 will assist the spring 19 in keeping the valve member 14 in its closed position after taking the sample and disconnecting the container 4 from the fitting 2.
The embodiments shown in
FIGS. 9 to 11 show an embodiment of the sampling device 1 comprising a nozzle 41 comprising a connecting piece 42 which may be connected with the fitting 2 and which has a tube connection 43 for the supply of or discharge of cleaning or washing fluid to or from the fitting 2. The tube connection 43 comprises an internal projection 44 which in the connected state of the nozzle 41 on the fitting 2 maintains the shielding member 25 in its open position, thereby allowing cleaning or washing fluid to pass in or out through the fitting 2.
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/IB03/00447 | 2/11/2003 | WO | 8/26/2004 |
