Title of Invention

FIXTURE FOR ROAD TRANSPORT OF LARGE TG STATOR WITH WEIGHT AROUND 270 TONS AND SUPPORT WIDTH MORE THAN TRAILER WIDTH

Abstract

This invention relates to fixture for road transport of large turbogenerator stator with weight around 270 tons having support width more than trailer width, comprising at least four structural members configured as a closed box type structure characterized in that; a plurality of support plates for releasably coupling by means of locking means on the turbo generator stator at predetermined heights; and at least one stopper plate for rigidly fixing the multi part cab structure device to the bed of the transportation means to prevent axial movement of the turbo generator stator, wherein a middle portion of the cab structure is designed at a longitudinally lower plane and wherein at least two side structural members forming side boxes are configured to extend outwardly longitudinally in an inclined plane. at least four structural members configured as a closed box type structure; a plurality of support plates for releasably coupling by means of locking means on the turbo generator stator at predetermined heights; and at least one stopper plate for rigidly fixing the multi part cab structure device to the bed of the transportation means to prevent axial movement of the turbo generator stator, wherein a middle portion of the cab structure is designed at a longitudinally lower plane and wherein at least two side structural members forming side boxes are configured to extend outwardly longitudinally in an inclined plane.

Full Text

FIELD OF INVENTION The present invention relates to built-in support structures for transportation of over-dimensional cargo (ODC). The invention particularly relates to fixture for road transport of large turbogenarator stator with weight around 270 tons having support width more than trailer width. BACKGROUND OF THE INVENTION The large size turbo generator stators with weight around 270 tons have length more than 7 meters and width as well as height more than 4 meter each. In the past, such large turbo generator stators have been transported by RAIL using specially-designed rail wagons. The large size turbo generator stators constitute Over-Dimensioned Cargo (ODC) of class/category *C due to restrictions over width and height profile of the consignment in rail transport. A very few of such specially-designed rail wagons are available in India which require approval by M/s. RDSO, Lucknow (Research and Development wing of Indian Railways). Further, many of the Thermal Power stations do not have railway tracks laid up to the power plant erection area and thus require that an alternative method be developed for transportation of ODC-cargo. Un-availability of adequate number of specialized rail wagons and /or owing to non-availability of the wagons preoccupied with transportation of another stator, maintenance etc. often causes large delays in dispatch, erection and commissioning of ODC-project equipment like turbo generator stators leading to time and cost over-run of projects/plants. Another disadvantage is that the turbo generator stators have their bottom surface curved like a cylinder and with projections for terminal bushing box and several flanges of various gas and water supply/drain connections. Hence turbo generator stators are required to be provided with suitable support plates at certain height for load transfer. Further, configurating a suitable cab structure for structural fastening of such irregular shaped over-dimensional equipment by maintaining dynamic structural stability poses a serious problem for the manufactures/logistics managers. OBJECTS OF THE INVENTION It is therefore an object of the present invention to provide fixture for road transport of large turbogenerator stator which is capable of structurally fastening ODC-cargo for example, turbo generator stators for safe transportation by trailors and / or wagons. Another object of the invention is to provide fixture for road transport of large turbogenerator stator which can sustain the load transfer from the turbo generator stator during the real time transportation phase. A further object of the invention is to provide fixture for road transport of large turbogenerator stator which comprises structural sections and plate sections of lighter weight so that the overall weight of the cab structure device remains optimum. A still further object of the present invention is to provide fixture for road transport of large turbogenerator stator which eliminates the above disadvantages of the prior art. Yet another object of the present invention is to provide fixture for road transport of large turbogenerator stator which is simple to fabricate and cost effective. SUMMARY OF THE INVENTION Accordingly, there is provided fixture for road transport of large turbogenarator stator with weight around 270 tons having support width more than trailer width, comprising at least four structural members configured as a closed box type structure; a plurality of support plates for releasably coupling by means of locking means on the turbo generator stator at predetermined heights; and at least one stopper plate for rigidly fixing the multi part cab structure device to the bed of the transportation means to prevent axial movement of the turbo generator stator, wherein a middle portion of the cab structure is designed at a longitudinally lower plane and wherein at least two side structural members forming side boxes are configured to extend outwardly longitudinally in an inclined plane. The stress analysis of the cab structure device for the loads coming on it during transportation has been worked out using Finite Element Method technique. An optimum design has been developed through a large number of variants analyzed out and using plates of different thickness and carrying out stress analysis on each variant. The finite element model has been prepared using symmetry for one quarter of the cab structure. During the analysis, adequate safety of the design has been ensured. BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS Further features and advantages of the invention become clear from the following description and drawings : Fig. 1 is a schematic arrangement showing large size turbogenerator stator and complete fixture with fixing arrangement and stopper plates. Fig. 2 is an end view of the Fixture when placed above a Road Trailer. Fig. 3 is a perspective view of Finite Element Model of one quarter of the Fixture created for carrying out an analysis of strength and design adequancy of Fixture against loads coming on it during transportation. Fig. 4 is a front view of the fixture of the invention. DETAILED DESCRIPTION OF A PREFFERED EMBODIMENT OF THE INVENTION As shown in Fig. 1, the fixture (2,3) has a closed box type of structure formed using steel plates with a long box of less height in the middle portion. All plates are connected at appropriate places with high quality welding using Supertherma electrodes. The side boxes (3) are inclined outwards since the width of the support plates of the turbogenerator stator is more than the available trailer width. The top plates of these side boxes are machined to provide proper seating and load transfer from turbogenerator stator support plates. Fixing of Fixture top plates with stator support plates is done using alloy steel bolts and nuts of high strength. Atleast one stopper plate (1) is welded onto the road trailer (4) in positions all around the Fixture structure (2,3) to prevent axial as well as transverse movement between the Fixture (2,3) and the Road Trailer (4). The lower part (2) of the fixture is placed on the trailor (4). The width of the stator at center and at its support plates is more than 4 meter while the typical width of a road trailer (4) is only about 3 meter. Hence the fixture (2,3,) is designed to have a V-type sides with a flat base (2) in middle, which matches with road trailer (4) width. The stator is supported on four independent fixtures (2,3) placed transversely, two at Turbine end and the other two at Exciter end. The Stopper plates (1) are provided in both axial and transverse directions for welding on the trailor (4) on the sides of the base plate (2) of the fixture, maintaining the fixture position on the trailer (4) during transportation. The fixture construction constitutes multi-box type being fabricated using high thickness steel plates so as to have sufficient strength against bending moments coming from the weight of the stator acting on the v-shape (3) portions of the fixture (2,3) overhanging from the trailer (4). The middle portion of the base plate (2) is contoured to accommodate the stator bottom circular portion including Exciter End projection. Finite Element Analysis has been carried out to design the geometrical details of fixture parts (2,3). Various design variants have been studied for achieving the optimum configuration of the fixture parts having adequate strength and without excessive load addition from the fixtures itself. Four steel plates of 60mm thick have been used in bottom portion (2) of the fixture. Lower thickness of plates has been used in upper portion (3) of the fixture. Welding sequences used in the box type structure (2,3) to ensure weld seams on both sides of steel plates carrying higher loads. Butt welds are used instead of fillet welds at selected locations to be subjected to high stresses. Besides forces and bending moments from the stator weight, axial and transverse forces coming from breaking/accelerating wind and path stoppage etc. have also been analyzed. This ensures that the fixtures (2,3) have adequate strength to bear all pertinent loads with adequate safety. The finite element model has been prepared using symmetry for one quarter of the fixture. During the analysis, adequate safety of the design has been ensured. An isometric view of the finite element model used is given in Fig. 3. WE CLAIM: 1. Fixture for road transport of large turbogenerator stator with weight around 270 tons having support width more than trailer width, comprising: ■ at least four structural members configured as a closed box type structure characterized in that; ■ a plurality of support plates for releasably coupling by means of locking means on the turbo generator stator at predetermined heights; and ■ at least one stopper plate for rigidly fixing the multi part cab structure device to the bed of the transportation means to prevent axial movement of the turbo generator stator, wherein a middle portion of the cab structure is designed at a longitudinally lower plane and wherein at least two side structural members forming side boxes are configured to extend outwardly longitudinally in an inclined plane. 2. Fixture for road transport of large turbogenerator stator with weight around 270 tons having support width more than trailer width as substantially herein described and illustrated with reference to the accompanying drawing.

Documents:

1748-del-2004-Abstract-(06-04-2010).pdf

1748-del-2004-abstract.pdf

1748-del-2004-Claims-(06-04-2010).pdf

1748-del-2004-claims.pdf

1748-del-2004-Correspondence-Others-(06-04-2010).pdf

1748-del-2004-correspondence-others.pdf

1748-del-2004-description (complete).pdf

1748-del-2004-description (provisional).pdf

1748-del-2004-Drawings-(06-04-2010).pdf

1748-del-2004-drawings.pdf

1748-del-2004-form-1.pdf

1748-del-2004-form-18.pdf

1748-del-2004-form-2.pdf

1748-del-2004-form-3.pdf

1748-del-2004-form-5.pdf

1748-del-2004-GPA-(06-04-2010).pdf

1748-del-2004-gpa.pdf