Floor structure for a railway freight wagon

Abstract: The invention relates to a flat floor (1) for a railway freight wagon, comprising longitudinal beams (5) along the lengthwise sides of a freight wagon, floor supports (4) therebetween comprising just a number of hat profiles (3) transverse to a freight wagon, which are fastened at ends (7) thereof to the longitudinal side beams of a freight wagon and which are downwards open. A floor panel is bonded with an adhesive to an upward-facing joint flange included in each hat profile (3) and connecting profile webs (8a, 8b).

Description: The invention relates to an at least substantially flat floor for a railway freight wagon, comprising longitudinal beams along the lengthwise sides of a freight wagon, floor supports therebetween, as well as a floor panel on top of the floor supports. Typically, the floors for railway freight cars, including support members therefor, are composed of a flat floor panel, either sheet steel or boards or the like, which is supported from below first by a number of lengthwise joists which are in turn supported by a number of crosswise joists which are in turn secured at the ends thereof to two longitudinal beams present along the sides of a railway freight wagon and having a length which covers the entire wagon. Examples of such conventional floor structures are described in the publication US-3,856,344, describing a road trailer, or in broad outlines in the publication DE-33 12 001 A1, wherein a floor panel is supported by a number of I-beams lengthwise of the wagon and adjacent to each other, and those are in turn supported by I-beams crosswise of the wagon, which are again secured to longitudinal girders present along the sides of a wagon. Thus, the floor structure disclosed in the cited publication is based on a truss frame system. The above-described floor is indeed rigid, as traditionally required, and such a floor may possess a sufficient strength, but it is complicated and extremely heavy and its manufacture is quite a tedious process. In addition, the floor supports include spots that are prone to collect, not so much water, but certain amounts of mud or the like. It is an object of the invention to provide a floor for a railway freight wagon, which would have a structure as simple as possible and easy to assemble and which would furthermore be clearly lighter than prior known truss frame floor structures. In this specification, the floor refers to a combination, comprising a structural element constituting a surface for the floor and beams and/or profiles supporting the floor within the confines thereof. A second object of the invention is that the floor strength must nevertheless be sufficiently good. A yet third object of the invention is a floor structure of the above type, which would have as few spots as possible to collect corrosion-activating media, such as water and dirt. The above problems can be resolved and the above objects can be accomplished by means of a floor structure of the invention, which is characterized by what is defined in the characterizing clause of claim 1. The most important benefit gained by the invention is that the inventive floor is extremely lightweight, yet sufficiently strong. This is partly based on the surprising discovery that the floor of a railway wagon need not be absolutely rigid, but it may have some resilience in a loaded condition and during running, and partly on the use of profile forms of the invention. At the same time, despite this resilience or elasticity, it has been possible to provide the inventive floor with a high-grade strength. Another surprising discovery has been that the bonding and riveting of structural floor elements securely to each other and to supports external of the floor results in a simple and strong, as well as a durable structure. The invention will now be described in detail with reference made to the accompanying drawings. Fig. 1 shows a floor of the invention generally in a view from below, i.e. upwards from railway tracks, and in an axonometric view. Fig. 2 shows a floor of the invention in a lengthwise elevation along a plane I-I in figs. 3 and 4. Fig. 3 shows a floor of the invention in a plan view from a direction II in figs. 1, 2 and 4. Fig. 4 shows a floor of the invention in a crosswise elevation along a plane III-III in figs. 1,2 and 3. The figure visualizes an at least substantially flat floor 1 for a railway freight wagon, comprising longitudinal beams 5 along the lengthwise sides of a freight wagon, floor supports 4 therebetween, as well as a floor panel 2 on top of the floor supports. According to the invention, the floor supports 4 only consist of a number of hat profiles 3 transverse to a freight wagon, which are secured at ends 7 thereof to said longitudinal side beams 5 of a freight wagon and which are downwards open. Thus, the inventive floor 1 does not include any freight-wagon length LL compliant, i.e. lengthwise supporting joists or bearing profiles between the two longitudinal side beams 5 of a wagon, but only crosswise hat profiles typically transverse to the longitudinal side beams. Each hat profile 3 consists of two webs 8a, 8b at a horizontal distance W1 from each other, a joint flange 10 connecting the same at the top edges thereof, as well as a bottom flange 9a, 9b pointing away from each other at the bottom edge of each web, such that the hat profile 3 is more or less in the shape of . Moreover, according to the invention, the floor panel 2 is bonded with an adhesive 6 to the upward-facing joint flange 10 of each hat profile connecting the webs 8a, 8b of a profile. Hence, the floor panel 2 only supports itself essentially on the joint flanges 10 of hat profiles. The hat profile 3 has a height H1, which is less, and preferably substantially less than a height H2 of said longitudinal beams 5. Typically, the height H1 of hat profiles is no more than 80% and often no more than 60% of the height H2 of longitudinal beams. The mutual ratio between the maximum height H1 of the hat profiles 3 and the maximum width W2 thereof, including the bottom flanges 9a, 9b, is within the range of 1:4-3:1, preferably within the range of 1:3-2:1. The adjacent and parallel hat profiles 3 have a distance W3 between the webs thereof closest to each other, which is 50%-200% of the distance W1 between two of said webs of a hat profile. It is obvious from this that the number of hat profiles 3 is in the order of twenty to forty in the floor of a freight wagon for the duty of supporting the floor panel 2. In order to fasten the hat profiles 3 against the longitudinal side beams 5 of a wagon, each hat profile is provided at each end thereof as an extension to each web 8a, 8b with elbows 13 pointing towards or away from each other. These elbows are set against the face-to-face surfaces of the webs of the longitudinal beams 5 and secured to said longitudinal beams 5 by means of rivets 14 extending through said elbows 13 and webs 15 of the longitudinal beams. The hat profiles 3 are only fastened to the longitudinal beams at the webs 15 thereof, not at all to top flanges 17 of the longitudinal beams, thereby avoiding the development of discontinuities which could in turn lead to an adverse condition, for example with regard to fatigue stress. According to the most preferred embodiment of the invention, each joint flange 10 of hat profiles comprises a row or rows J1 and J2 of circular or oblong holes 11, which is/are substantially parallel to a length L1 of the hat profile 3. In the embodiment of fig. 3, the holes 11 present in various rows J1, J2 are in line with each other or side by side along the length L1 of a hat profile. Alternatively, the holes 11 of various rows J1, J2 are in alternating positions along the length L1 of a hat profile. Regarding the hat profiles, each web 8a, 8b is also preferably provided with a row, or optionally, rows of circular or oblong holes 12, which is/are substantially parallel to the length L1 of a hat profile. The figures only depict a single row of web holes 12, but obviously there may be more than that, the successive holes 12 being at alternating levels in the web or coinciding with each other as in the joint flange 10. The bottom flanges 9a, 9b may also include holes, or be intact, depending on other dimensions. It is obvious that the joint flange 10, the webs 8a, 8b, and the bottom flanges 9a, 9b may all be intact or just one type of section thereof may include holes or two different types of sections may include holes, as in the illustrated embodiment, or all types of sections may include holes, without departing from the scope of the invention. In principle, the hat profiles 3 may be asymmetrical in numerous ways, but the most preferred solution is to use a symmetrical hat profile. Likewise, it is preferred that just one type of hat profile be used across the entire length LL of a wagon floor, although there is nothing to prevent the use of various types of hat profiles in various sections of the floor. In hat profiles, each bottom flange 9a, 9b has preferably an equal width for a symmetrical hat profile, as described above. Moreover, each individual bottom flange 9a and 9b has a width W4, which as measured from its web 8a and 8b, respectively, is 15%-50% of the inter-web distance W1, equalling the width of a joint flange. It should be appreciated that the dimensions set forth in this context, as well as those foregoing dimensions regarding the floor along with its supports, are merely given in the way of guidelines and the dimensioning can be carried out as required by a particular situation and railway freight wagon. Said floor panel 2 is preferably made in water-proof plywood or the like and said adhesive 6 comprises at least somewhat elastic synthetic polymer, available in a plurality of types suitable for this purpose, such as polyurethane adhesives or the like. Hence, this adhesive 6 is not described in more detail. Said longitudinal beams 5 comprise a vertical web 15 and a bottom flange 16, as well as a top flange 17. The longitudinal beams present along the opposite sides of a wagon have the top flanges 17 thereof extending from the webs 15 thereof towards each other, forming a space L2 therebetween, and the top flanges have an effective thickness H3a which is substantially equal to a thickness H3b of said floor panel. In this embodiment, the top flanges 17 of longitudinal beams have a material thickness H4 which is less than the floor panel thickness H3b and the top flange has its face-to-face edges bent downwards for an elbow having a height which is equal to the floor panel thickness, the top flange being in contact with the entire thickness of the floor panel 2. Of course, it is possible to provide the longitudinal beams with an even thicker top flange. The floor panel or floor panels 2 is/are adapted to have such a width that the space L2 between the top flanges of longitudinal beams is/are filled thereby. In addition, each longitudinal side beam 5 of a wagon is provided with more or less triangular reinforcements 19 set between its web 15 and top flanges 17 pointing away from each other. The web 15 of said longitudinal beams is provided with lightening holes 20 in the mid-section of its height H2. It is obvious that both the hat profiles 3 and the longitudinal side beams 5 of a wagon, as well as the floor panel 2, have thicknesses thereof dimensioned according to loads existing in a railway wagon. However, as long as a railway freight wagon is properly designed in terms of its other details, the wagon floor can be made more elastic or resilient than what it used to be.

Claims: An at least substantially flat floor (1) for a railway freight wagon, comprising longitudinal beams (5) along the lengthwise sides of the freight wagon, floor supports (4) therebetween, as well as a floor panel (2) on top of the floor supports, characterized in that the floor supports (4) only consist of a number of hat profiles (3) transverse to a freight wagon, which are secured at ends (7) thereof to said longitudinal side beams (5) of the freight wagon and which are downwards open; and that the floor panel (2) is bonded with an adhesive (6) to an upward-facing joint flange (10) included in each hat profile and connecting webs (8a, 8b) of the profile. A freight wagon floor as set forth in claim 1, characterized in that the hat profile (3) consists of two webs (8a, 8b) at a horizontal distance (W1) from each other, a joint flange (10) connecting the same at the top edges thereof, as well as a bottom flange (9a, 9b) pointing away from each other at the bottom edge of each web; and that the hat profile (3) has a height (H1) which is less than a height (H2) of said longitudinal beams (5). A freight wagon floor as set forth in claim 1 or 2, characterized in that the hat profile (3) has a maximum height (H1) and a maximum width (W2), including the bottom flanges (9a, 9b), the ratio therebetween being within the range of 1:4-3:1, preferably within the range of 1:3-2:1; and that the closest-together webs of adjacent hat profiles (3) have a distance (W3) therebetween, which is 50% - 200% of the distance (W1) between two webs of a hat profile. A freight wagon floor as set forth in claim 1 or 2, characterized in that the hat profiles have each bottom flange (9a, 9b) equal in width and each individual bottom flange has a width (W4) extending from its web, which is 15%-50% of the inter-web distance (W1) or the width of a joint flange. A freight wagon floor as set forth in any of the preceding claims, characterized in that the hat profiles have each joint flange (10) comprising a row or rows (J1, J2) of circular or oblong holes (11), which is/are substantially parallel to a hat profile length (L1), or in which the holes (11) of various rows are located in an alternating fashion along the length of a joint flange. A freight wagon floor as set forth in any of the preceding claims, characterized in that the hat profiles have each web (8a, 8b) comprising a row or rows of circular or oblong holes (12), which is/are substantially parallel to a hat profile length (L1), or in which the successive holes (12) are located at alternating levels in a web. A freight wagon floor as set forth in any of the preceding claims, characterized in that the hat profiles (3) have the ends thereof provided, as an extension to the webs (8a, 8b), with elbows (13) directed either towards each other or away from each other; and that the hat profiles are in contact with said longitudinal beams (5) by means of rivets (14) extending through the elbows and the longitudinal beams. A freight wagon floor as set forth in any of the preceding claims, characterized in that said floor panel (2) is made in water-proof plywood or the like; and that said adhesive (6) comprises some elastic synthetic polymer. A freight wagon floor as set forth in claim 1 or 8, characterized in that said longitudinal beams (5) comprise a vertical web (15) and a bottom flange (16), as well as a top flange (17), that the top flanges (17) of the longitudinal beams present along the opposite sides of the wagon extend from the webs thereof towards each other and have a thickness (H2) which is substantially equal to that of said floor panel; and that the floor panel(s) (2) fills/fill a space (L2) between these top flanges of the longitudinal beams.

Inventors: HEIKKINEN JAAKKO, MAEENPAEAE OLAVI, HEIKKINEN, JAAKKO, MAEENPAEAE, OLAVI, Mäenpää, Olavi
Applicants: TALGO TRANSTECH OY, TALGO-TRANSTECH OY
Application year: 2001
Main classification: B61D17
IPC codes: B61D17, B62D25