Field of the Invention The present invention relates to a ductwork for leading at least one pipe through a cir cular opening in a partitioning wall as well as a method for installing such a ductwork in a partitioning wall and the use of such ductwork and such method.

The ductwork includes: - a flange member, where said flange member has a pipe section with an inner diameter, wherein connected to the pipe section adjacent one end of said pipe is arranged a flange, said flange extending radially away from said pipe section in a plane substantially or thogonal to a longitudinal direction of the pipe section, and where one or more apertures are provided through said flange; - a gasket dimensioned to be positioned on said flange, where a first aperture is arranged centrally in said gasket, said aperture having a diameter larger than the inner diameter in the pipe section, and in use arranged on the flange such that the aperture is superposed the pipe section, and where further one or more second apertures are provided through the gasket, such that in use the one or more second apertures may be aligned/superposed with the one or more apertures in the flange;

- a counter plate, which in use is to be positioned on the opposite side of the partitioning as to the flange member and the gasket, where the counter plate has a central aperture, and where the counter plate in a plane orthogonal to the aperture, has a non-circular cross-section, having a minor dimension across the counter plate and a major dimension across the counter plate in a direction different from the minor dimension, and where one or more studs extends from a first surface of the counter plate, such that the one or more studs may be inserted through the one or more second apertures in the gasket and the one or more apertures in the flange of the flange member. Background of the Invention

An example of a ductwork of this type is known from the same applicant’s prior patent EP 2,635,831 B1 in which a ductwork is described for leading a pipe through a hole in a partitioning. The ductwork comprises a flange and a number of connecting arrange ments such that the flange may be arranged in the opening in the partitioning. The con necting arrangement includes a force transmission means which cooperate with the flange by means of a bolt connection such that the force transmission means may be pivoted from a position where they are able to pass through the opening in the partition ing wall to a position where they are extending radially from the centre of the ductwork on a rear side of the partitioning wall. Thereafter by tightening the bolts it is possible to fasten the ductwork to the hole in the partitioning. This system although being easy to operate and very reliable does not facilitate the use of a tightening means, for example in the shape of a gasket or other joint materials and furthermore relies on three substan tially separate connecting arrangements in order to achieve a firm mounting on the par titioning wall.

WO 2019/057855 A1 disclose a ductwork of the type is of the type defined by way of introduction and as defined in the preamble of claim 1. There is no disclosure of the use of an intermediate plate having apertures arranged such that the one or more studs in the counter plate may pass through one or more apertures in the intermediate plate.

Object of the invention The present invention aims at alleviating these drawbacks and providing further ad vantages.

Description of the invention

Consequently, the present invention provides a ductwork for leading at least one pipe through a circular opening in a partitioning wall, the ductwork is of the type defined by way of introduction and as defined in the preamble of claim 1 and which ductwork is peculiar in that an intermediate plate member is provided, said intermediate plate mem ber being provided with one or more apertures, said apertures arranged such that the one or more studs in the counter plate may pass through the one or more apertures.

With this construction of a ductwork it is possible to create a very tight and firm fit around the opening in the partitioning and at the same time by relatively simple means a few separate parts, assure that the ductwork is mounted in the correct position in the correct manner. The flange member does include a pipe section and foresee that the pipe which is desired to pass through the partitioning wall is safely guided through the wall and received in a proper manner in the pipe section already arranged in the flange. The combination of flange and pipe section allows for a sturdy and strong ductwork and as such allows for a very reliable pipe transition through a partitioning wall. At the same time by proving a relatively large gasket retained by the flange and furthermore kept in place by the studs being threaded through the apertures (both in the gasket and flange) it is assured that the gasket is correctly placed with respect to the pipe section and the opening in the partitioning wall and that although being manipulated in order to fit the ductwork into the proper position relative to the apertures in the partitioning wall, the gasket remains in place and is able to fulfil its purpose, namely creating a substantially tight connection between the partitioning wall and the ductwork allowing the pipe to be led through the partitioning wall. Furthermore, the counter plate being provided with studs, which studs may be threaded through the apertures provided in the gasket and in the flange of the flange member, provides for easy assembly and a safe and very intui tive manner in which to assemble the three parts without welding or cutting.

Furthermore, by providing the counter plate with a non-circular cross-section such that a minor dimension is smaller than the opening in the partitioning wall, it is possible to insert the counter plate through the hole in the partitioning. Due to the counter plate having a major dimension across the counter plate in a direction, different from the minor direction, it is possible to manipulate the counter plate into a position on the other side of the partitioning wall, from which the flange member is to be arranged and as the major dimension being larger than the opening in the partitioning wall, assuring that the counter plate provides resistance when the flange member is mounted on the studs ex tending from the counter plate. One possible shape of the counter plate may be oval such that the major dimension is the largest dimension and the minor dimension is the smallest cross dimension in an oval shape counter plate. A further possible shape might be rectangular or any variation as long as the relationship between the minor dimension and the major dimension facilitates the above mechanisms, i.e. that it is possible to insert the counter plate through the aperture in the partitioning wall by arranging the counter plate with its minor dimension to pass through the apertures, thereafter assuring that the major dimension provides overlap on the other side of the partitioning wall whereby it becomes possible to tighten the flange member against the partitioning wall, such that the counter plate will provide the necessary resistance.

At the same time the apertures in the gasket and the flange member being positioned such that the studs from the counter plate may be threaded through apertures, assures that the gasket is retained in the correct position relative to the flange member such that a correct fit and mounting may be obtained.

The intermediate plate member is also provided with apertures such that the studs of the counter plate may be threaded through the intermediate plate member and thereby re tained the intermediate plate member in a substantially fixed position with respect to the counter plate, the gasket and the flange member. In this manner the intermediate plate member may assist in stabilizing the gasket and thereby reinforcing the flange member as such, whereby a tight and stable fit is further improved by the provisioning of the intermediate plate member.

The intermediate plate member may in a further advantageous embodiment have an outer periphery defining a first shape, and where the gasket is provided with a substan tially flat central region suitable to accommodate the first shape, and where the gasket outside the central region is provided with one or more concentrically arranged ridges circumscribing the central region, said ridges being raised relative to the flat central region.

In this embodiment of the intermediate plate member the intermediate plate member is active in positioning the gasket and at the same time the ridges provided in the gasket, for example extending above the gasket central area to such a degree that they also extends more than the thickness of the intermediate plate member, will in addition to retaining the gasket in its correct position with respect to the through going aperture in which the pipe through the partitioning wall is to be fit, also assures that the gasket does not buckle or fold. The intermediate plate thereby retains the gasket with its tightening function, when the flange member is fastened through a partitioning wall by means of the studs from the counter plate. The intermediate plate member may also, in a further advantageous embodiment be provided on the side which use is intended to face away from the gasket, with a pack aging or gasket material, which packaging or gasket material when exposed to fire will expand. In this manner the intermediate plate member also becomes an additional gas- ket having special properties for special situations. This is particularly advantageous when this type of ductwork is used in partitioning walls, for example in ships or other places where it might be difficult to gain access such that the additional protection against spread of fire will provide an extra barrier. In a further advantageous embodiment the flange along an outer periphery is provided with a bent rim thereby forming an edge upstanding from the flange, where the inner dimension of the flange delimited by the bent rim can accommodate the gasket. In this manner a shallow dish shape suitable to accommodate the gasket is provided on the flange, whereby mounting of the gasket and retaining the gasket in its correct position is further facilitated.

When assembling the ductwork according to the present invention by manipulating the counter plate through the opening in the partitioning wall and threading the gasket and flange member over the studs extending from the counter plate, the ductwork may be tighten, for example by providing a thread on the studs and after having threaded the studs through the apertures of the intermediate plate the gasket and the flange member be tighten together by means of nuts. Also, other means of tightening may be used in order to urge the counter plate towards the flange member once the ductwork is installed around a hole and a partitioning wall.

The invention is also directed to a method of installing a ductwork as described above for creating a pipe transition through a partitioning wall, the method comprising the following steps: a) creating a circular hole in the partitioning, where the hole in size corresponds to at least the outside diameter of the pipe which shall pass through the partitioning; b) selecting ductwork having the desired pipe dimensions, corresponding to the pipe diameter which it is desired to pass through the partitioning; c) manipulating the counter plate where the counter plate has a central aperture having a diameter larger than the inner diameter of the pipe section, and where the counter plate in a plane orthogonal to the aperture, has a non-circular cross-section, where a minor dimension across the counter plate is smaller than the opening in the partitioning wall, and a major dimension across the counter plate in a direction different from the minor dimension, is larger than the opening in the partitioning wall, and where one or more studs extends from a first surface of the counter plate, through the hole in the partition ing by inserting the counter plates minor dimension through the hole in the partitioning and arranging the studs so they extend through the hole; cl) threading an intermediate plate member over the studs and pushed against the par titioning wall; d) threading the apertures in the gasket over the studs; e) threading the apertures in the flange of the flange member, over the studs; f) providing means on the studs such that it is possible to urge the counter plate towards the flange member. The method of course utilizes and enjoys the advantageous of the ductwork as already described above.

A further embodiment of the inventive method is described in the further claims. The present invention is also directed to the use of the ductwork for leading at least one pipe through a circular opening in a partitioning wall, which use involves that the distance from the center of the central aperture to the one or more studs is smaller than the radius of the circular opening in the partitioning. The present invention is also directed to the use of the ductwork for leading at least one pipe through a circular opening in a partitioning wall, which use alternatively involves that the minor dimension across the counter plate is smaller than the opening in the partitioning wall, and the major dimension is larger than the opening in the partitioning wall.

The present invention is also directed to the use of the method for leading at least one pipe through a circular opening in a partitioning wall, which use involves that the minor dimension across the counter plate is chosen smaller than the opening in the partitioning wall, and the major dimension is chosen larger than the opening in the partitioning wall. Description of the drawing

The invention will now be described with reference to the accompanying drawing, wherein

Figure 1 illustrates a cross-section through a ductwork according to the present invention

Figure 2 illustrates an exploded view of the ductwork Figure 3 illustrates the ductwork from the assembly side of the partitioning wall Figure 4 illustrates the assembly from the opposite side of the partitioning wall, i.e. the side of the partitioning wall which has not been accessed

Figure 5 illustrates a cross-section through a bulkhead in which an assembly according to the invention has been installed. In Figure 1 is illustrated a cross-section through a ductwork according to the present invention. The ductwork 1 comprises a flange member 2, which flange member 2 com prises an integral pipe section 3. The pipe section 3 is in one end connected to a flange 4 which flange extends radially away from the pipe section 3. The flange section 4 is furthermore provided with a bent rim 5 such that the flange 4,5 is shaped like a shallow dish.

Inside the shallow dish delimited by the bent rim section 5 and the flange 4 is provided a resilient gasket 6. The gasket 6 fits inside the bent rim portion 5 such that the bent rim portion 5 will assist in guiding the gasket into a correct position. In this position a central aperture 7 provided in the gasket 6 will be superposed the opening in the pipe section 3. Furthermore, the gasket 6 is provided with upstanding ridge portions 8, 8’ which are concentrically arranged with respect to the apertures 7 such that the ridge portions 8, 8’ are equidistantly spaced from the rim section 5 of the flange 4. The ductwork 1 is furthermore provided with an intermediate plate member 9 which intermediate plate member 9 is provided with a central aperture 10. The central aperture is positioned substantially centrally in the intermediate plate member 9 such that a con tinuous opening is provided through the aperture 10 of the intermediate plate member 9 and the aperture 7 in the gasket 6 and the pipe section 3. In this embodiment the intermediate plate member 9 has an outer dimension such that it will fit inside the innermost ridge member 8’ in the gasket, i.e. in a flat central section of the gasket. In this manner the intermediate plate member will help to stabilize the gasket such that, as the ductwork is installed in a partitioning wall (not illustrated) the intermediate plate member will make sure that the gasket is not displaced, folded or otherwise manipulated into a position which does not fulfil the gasket’s function.

The intermediate plate member 9 is in this embodiment constructed as a triple member. The first part 13 may be a steel plate or other rigid member which may fulfil the function as described above by keeping the gasket 6 in its correct position. The upper layer 12 is an intumescent (fire protective) layer which will expand when exposed to heat, for ex ample a fire. A secondary fire protective layer 11 is a fire impregnated foam, for exam ple a polyurethane foam. In this case the layer 12 will expend and cover any irregulari ties in the fit between the ductwork of the present invention and the partitioning wall to which it is mounted. For example a steel partitioning wall may deform when exposed to fire, and by providing the fire protective expansive layer, it will to a certain degree be possible to maintain the tight fit even with considerable deformation of the partition ing wall. The first layer may have a thickness of 4 mm whereas the second layer is approx. 10 mm.

Examples of suitable intumescent material may be obtained as Envirograf® Multigraf, but also other makes are useful.

Finally, the ductwork as illustrated in Figure 1 comprises a counter plate 15. The counter plate is as will be explained with reference to Figures 2 and 3 in this embodiment shaped with an oval cross-section orthogonal to the aperture 16 provided in the counter plate. Furthermore, the counter plate is provided with a number of studs 17. These studs ex tend substantially perpendicular from the plane of the counter plate 15. Furthermore, the intermediate plate 9, the gasket 6 and the flange 4 are all provided with apertures which may be superposed such that the studs may be inserted through the overlapping apertures in the intermediate plate 9, the gasket 6 and the flange 4 such that the studs on the free side of the flange 4 may be provided with nuts 18. In the embodiment described with reference to the Figures, the counter plate 15 is provided with four studs 17 ar ranged perpendicular to the counter plate. Naturally, any suitable number of studs may be arranged, for example 3, 5 or more depending on the size of the ductwork and the necessity to assure that the counter plate 15 is able to provide sufficient pressure to the ductwork around the partitioning wall in order to create a watertight connection. Also, more than one pipe section may be provided extending from the flange. The skilled person will realise to arrange the inventive features accordingly in order to real ise the invention with more pipe sections. This will naturally require a gasket with ap ertures, an intermediate plate with more apertures etc. The counter plate shall naturally retain its properties relating to major and minor axis, but otherwise be designed to ac- commodate the plurality of pipe sections.

The ductwork is illustrated in an exploded view in Figure 2 where the same parts of the ductwork are provided with the same reference numbers. The pipe section 2 is provided with a circular pipe 3 connected to the flange 4. In order to assure a tight connection with the pipe to be inserted into the pipe section, an internal gasket 20 is provided, in this embodiment in the zone where the flange 4 interfaces the pipe section 3. Further more, the flange 4 is provided with four apertures 21 which have a size and are distrib uted such that it will be able to receive the studs 17 from the counter plate 15. Likewise, the gasket 6 is provided with apertures 2G as is the intermediate plate member with apertures 21 ” . In this manner once the gasket 6 is positioned on the flange 4 inside the bent rim portion 5 and the intermediate plate member 9 is arranged on the gasket 6 it is possible to insert the studs 17 through the overlapping second apertures 21, 21’, 21” and in this manner access the distal ends of the studs 17 from underneath the flange 4 (in the orientation illustrated in the fig).

In order to accommodate the intermediate plate member 9, the gasket is provided with a flat central region 23 which extends from the first aperture 7 provided in the gasket towards ridge members 8 arranged concentrically around the aperture 7. This flat central region 23 is provided in order to accommodate the intermediate plate member 9 such that a flat and tight fit will be provided between the intermediate plate member 9 when arranged inside the central flat section 23 of the gasket 6. For this reason the flat section 23 has a radial extend sufficient to accommodate the intermediate plate member 9. The counter plate is provided with an oval cross-section in a plane perpendicular to a central axis 50 through the ductwork. The oval shape is defined by a minor axis 25 and a major axis 27.

When arranging the ductwork around a circular aperture in a partitioning wall the cir cular opening in the partitioning wall shall have a diameter corresponding to the dimen sion of the counter plate along the minor axis 25. In this manner it is possible to manip ulate the counter plate 15 through the opening in the partitioning wall and then when flattening the counter plate 15 against the surface of the partitioning wall (on the oppo site side to where the work is carried out from), the dimension of the counter plate 15 along the major axis 27 is larger than the diameter of the aperture in the partitioning wall such that the counter plate may be tighten against the partitioning wall due to the overlap of the counter plate along the major axis 27.

When mounting the ductwork according to the present invention the counter plate 15 is initially arranged as described above on one side of the partitioning wall. Once the coun ter plate 15 is arranged, the studs 17 will extend through the aperture in the partitioning wall after which the intermediate plate member 9 is threaded onto the studs followed by the gasket and the pipe section 2 (with the flange). Once these members are in place the distal ends of the studs 17 will extend on the rear side of the flange 4. At this time it is possible to thread nuts (see Figure 1) onto the distal ends of the studs and by tightening the nuts compressing the ductwork around the aperture in the partitioning wall.

At this time the ductwork according to the present invention will, from the assembly side of the partitioning wall, look like the illustration in Figure 3.

From the opposite side of the partitioning wall, i.e. the side of the partitioning wall which has not been accessed, the assembly will look like the illustration in Figure 4. In this illustration the partitioning wall is invisible. The counter plate 15 with the oval shape with fastening means for the studs 17 as well as the aperture 7 going through the partitioning wall and potentially the gasket 20 inside the pipe section 3 will be visible inside the aperture 7. The gasket 6 will be hidden by the partitioning wall, but for illus trative purposes the partitioning wall has been made invisible such that it is possible to view the gasket and the concentrically arranged ridges 8, 8’. In fig 5 is illustrated a cross-section through a bulkhead wherein an assembly according to the invention is mounted. The parts of the assembly/ductwork are identified by the same reference numbers as used above. As appears from the description above the counter plate 15 is oval having specific di mensions relative to the aperture in the bulkhead or partitioning 25 in which the duct work is to be installed. After having been manipulated into place the counter plate will be positioned such that a portion of the counter plate will overlay the bulkhead 25. In the illustration in fig. 5, the counter plate 15 is illustrated in a cross section along the shorter axis 25 (see fig. 2) - therefore the counter plate does not overlap the bulkhead, as would be the case had the cross-section been made along the longer axis 27 (see fig 2 again).

By further tightening the nuts 18 on the studs 17, the counter plate is forced against the bulkhead 25 and at the same time the gasket 6 is also forced against the bulkhead - thereby creating a tight transition of ductwork through a bulkhead/partitioning.

Above a particular embodiment of the invention has been described; however, it will be clear to a person skilled in the art that many variations of the invention are possible. For example, the number of ridges provided in the gasket may be more or less as well as the number of studs projecting from the counter plate 15 may also be any suitable number. A further aspect which should also be clear to a person skilled in the art is that the thickness and resiliency of the gasket 6 shall be chosen according to circumstances, and although the intermediate plate member has been described above, it is clear that in some embodiments it may be advantageous not to have an intermediate plate member or as in other embodiments, particularly where the requirements are such that the risk of fire spreading should be avoided, an intermediate member with a fire gasket com pound should be used. In some embodiments of the invention the complete and assembled ductwork is deliv ered to the personnel who shall have to install the ductwork in-situ. This of cause has the great advantage that the installer does not have to keep track of the parts of the ductwork, does not risk assembling the various parts incorrectly etc. Furthermore due to the inventive geometrical relationship of the counter plate with respect to the opening in the bulkhead, it is not necessary to disassemble the ductwork, and all operations may be performed from one side of the ductwork.

Also, it is contemplated that the studs may be in the shape of bolts. In those embodi- ments the counter plate is either provided with means for hindering the bolt heads to rotate during the mounting procedure, or it is necessary to have access to both sides of the bulkhead.