Patent Application
20140191537
The present disclosure relates to a grating, more particularly to a platform grating for large machines.
Platform gratings are used as floor members for machine platforms provided on large machines. These platforms provide ingress and egress to various parts of the machine for operational and/or maintenance purposes. Besides large machines, such platforms are also widely used in industrial premises and on process equipment.
Currently known methods of manufacturing of the platform gratings includes arranging a plurality of plates or bearing bars parallel to each other in a spaced apart arrangement. The plates are securely held in position by a plurality of hollow tubes or rods which are placed perpendicular to the plates and parallel to one another. The hollow tubes are fastened or attached to the plates by welding, bolting, riveting, or any combination thereof. However, individually welding each of the joints of the hollow tube and the plate proves to be time consuming and expensive activity.
Hence, there is a need to provide an improved manufacturing method for the platform gratings which overcomes the above mentioned shortcomings.
In one aspect of the present disclosure, a platform grating is provided. The platform grating includes an array of plates placed in a spaced apart arrangement. Each of the array of plates includes a plurality of apertures which are provided in transverse alignment with the apertures in the adjacent plate. The platform grating also includes an array of hollow tubes positioned within the apertures provided in the array of plates. Each of the array of hollow tubes is mechanically connected to the array of plates.
In another aspect of the present disclosure, a method of manufacturing a platform grating is provided. The method provides a plurality of apertures in each of an array of plates. The method arranges each of the array of plates in a spaced apart arrangement in such a manner that the apertures of one plate are provided in transverse alignment with the apertures in the adjacent plate. Further, the method positions an array of hollow tubes through the provided apertures. An outer diameter of the hollow tube is less than a diameter of the aperture. Thereafter, the method expands the diameter of the each of the array of hollow tubes to mechanically secure the hollow tube with the plate.
Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.
Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.
Referring to
More specifically, the platform grating 204 may include a mesh type configuration including an array of plates 208 and an array of hollow tubes 210 placed in a spaced apart arrangement. The present disclosure relates to the platform grating 204 in which each of the hollow tubes 210 is mechanically connected to the plates 208.
Referring to
In one exemplary case, the plate 208 may have the width “W” of approximately 1500 mm, the height “H” of approximately 40 mm, and the thickness of approximately 4 mm. Also, the aperture 302 provided on the plate 208 may have the diameter of approximately 13 mm. The spacing provided between any two adjacent apertures 302 may be approximately 30 mm in one exemplary case.
Additionally, as shown in
Moreover, the hollow tube 210 is configured to be positioned within the aperture 302 provided on the plate 208. An exploded view of the hollow tube 210 is shown in
In the present disclosure, the hollow tube 210 is mechanically connected to the plate 208 by expanding the inner diameter “ID1” of the hollow tube 210. It should be noted that expansion of the inner diameter “ID1” causes an outer surface of the hollow tube 210 to cooperate with an inner surface of the aperture 302. More specifically, the hollow tube 210 forms an interference fit within the one or more apertures 302. In order to expand the hollow tube 210, a mandrel 500 (shown in
As shown in
In one embodiment, a taper 506 may be provided on a surface of the mandrel 500 such that there is a change in the diameter of the mandrel 500 on either side of the taper 506. Alternatively, the mandrel 500 may have a conical shaped configuration to provide a continuous graduation in the diameter between the first and second ends 502, 504 of the mandrel 500. In another embodiment, the first and second ends 502, 504 may have the same diameter. The mandrel 500 may be made of metal, such as, flame hardened mild steel.
It should be noted that dimensions and material used for the mandrel 500 may vary depending upon the manufacturing process needs and system requirements. In one example, the diameter of the second end 504 may be approximately 10.55 mm. Moreover, the mandrel 500 may have an axial hole 508 drilled through it. In one embodiment, a steel cable (not shown) may be passed through the hole 508 of the mandrel 500 to enable pulling of the mandrel 500 along an inner surface of the hollow tube 210.
Once fitted within the hollow tube 210, the mandrel 500 may be pulled or pushed through the full length “L” of the hollow tube 302 in a variety of ways. In one embodiment, the cable is attached to the second end 504 of the mandrel via the hole 508 present in the mandrel 500. The cable may be attached to the mandrel 500 by a hook, clasp, knot, or any other known method. The cable is made to pass through the hollow tube 210. The mandrel 500 and the attached cable may then be pulled through the full length “L” of the hollow tube 210. Alternatively, in another embodiment, the mandrel 500 may be pushed through the full length “L” of the hollow tube 210 using a hydraulic press, a pneumatic press, or any other similar method known in the art.
Due to the expansion of the hollow tube 210, there may be an increase in the initial inner diameter “ID1” of the hollow tube 210 by approximately 3 to 7%. One of ordinary skill in the art will appreciate that the increase in the inner diameter “ID1” of the hollow tube 210 causes a corresponding increase in the outer diameter “OD1” of the hollow tube 210, shown as an outer diameter “OD2” in
In one embodiment, the outer diameter “OD1” of the hollow tube 210 may expand by approximately 2 to 5%. Correspondingly, the wall thickness “T1” of the hollow tube 210 may decrease by approximately 1 to 5%. Accordingly, a shoulder height “SH” (see
The interference fit shown in
An exemplary method 900 for the manufacture of the platform grating 204 will be described in connection with
Platforms making use of a grating as a floor member are generally provided on large machines for ingress and access to the operator cabin and other sections of the machine. Known platform gratings make use of methods like welding, bolting, riveting, and the like at an intersection of the hollow tube and the plate, in order to hold the grating structure in place. Since the platform grating has a number of such intersections, individually joining each intersection is a laborious and expensive activity. The present disclosure provides a cost efficient and simpler approach for the manufacture of the platform grating 204, further reducing assembly time involved therein.
At step 902, the apertures 302 are provided in each of the plates 208 in an equally spaced arrangement. The spacing between each of the apertures 302 may be based on the application. Further, parameters like size of the apertures 302, number of the apertures 302, and the like may vary. At step 904, the plates 208 are arranged parallel to each other in a spaced apart arrangement within the apertures 302 of one plate 208 which are transversely arranged with respect to the apertures 302 of the adjacent plates 208.
Thereafter, at step 906, the array of hollow tubes 210 are positioned within the apertures 302 in such a manner that each of the hollow tubes 210 is spaced apart from each other in a parallel arrangement. The mandrel 500 is then directed through the full length “L” of the hollow tube 210. In one embodiment, the cable is attached to any one end of the mandrel 500. The mandrel 500 and the attached cable are then pulled through the full length “L” of the hollow tube 210. In another embodiment, the mandrel 500 may be pushed through the full length “L” of the hollow tube 210 using the hydraulic press, pneumatic press, or any other method known in the art.
At step 908, the inner diameter “ID1” of the hollow tube 210 is expanded in order to mechanically secure the hollow tube 210 with the plate 208. One of ordinary skill in the art will appreciate that the diameter of the mandrel 500 may be relatively larger than the inner diameter “ID1” of the hollow tube 210. This may result in the expansion of the inner diameter “ID1” the hollow tube 210 when the mandrel 500 is passed through it. To this end, the interference fit between the outer surface 702 of the hollow tube 210 and the inner surface 704 of the aperture 302 is created at the joint 700. It should be understood that the disclosure described herein can be used in a variety of applications making use of the platform grating 204.
While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.
