DREDGE PUMP SET

Abstract: A dredge pump for a dredge craft, such as a trailing suction dredger in which a tubular carrier is present for the pump set and the drive set is connected to the pump shaft, whereas the shaft side of the pump body is fastened to the one end of the tubular carrier in which the pump shaft and the drive set are housed, and the other end of the tubular carrier can be fastened to a support structure. The novel apparatus comprises two or more bearings (21, 22, 23) for the pump shaft (17) of the drive set, that are housed in a tubular bearing body (20) of which the ends are sealed, whereas at least two support elements, (24) (25) that extend from the inner wall of the tubular carrier (15) in an inward direction, are fastened to the outside of the tubular bearing body (20), said pump shaft (17) being independent from the motor shaft (26) and said shafts being connected by a coupling (30), which coupling preferably being an elastic coupling.

Description: Title of the invention: Dredge pump set". The invention relates to a dredge pump set for a dredge craft, comprising a tubular carrier for the pump set and the drive set that is connected to the pump shaft, in which the shaft side of the pump body is fastened to the one end of the tubular carrier in which the pump shaft and the drive set are housed, whereas the other end of the tubular carrier can be fastened to a support structure, which tubular carrier has been provided with at least one support element, that extends from the inner wall of the tubular carrier in an inward direction and has a bearing for the pump shaft and the drive set. Dredge pump sets of this type are described in "PORTS AND DREDGING", No. 86, 1975, "centrifugal dredge pumps", No. 7, pages 8, 9; fig. 13. There are used mainly in a submerged condition as a part of a suction trailing or towing tube. The pump shaft and the motor shaft are unitary whereas the electric motor is mounted on the inside of the tubular carrier, said single shaft being supported in bearings at both ends of the electric motor. This structure has the objection, that bending forces on the trailing or towing tube have their effect on the unitary pump-motor shaft, so that -the bearings become quickly v rn out whereas the removal and replacement of these bearings require considerable labour and result in a certain amount of down time for the dredge pump set and thus the craft that has been equipped therewith. The object of the invention is providing an improved dredge pump set of the type described in the preamble, said set having on the one hand such a shaft and bearing construction, that the shaft and bearings are substantially unnfluenced by bending forces on the connected suction tube, and are on the other hand easy replacable so that the labour and the down time for replacement are substantially reduced. This object is reached according to the invention, in that the drive set comprises two or more bearings for the pump shaft, that are housed in a tubular bearing body of which the ends are sealed, whereas at least two support elements are fastened to the outside of the tubular bearing body, said pump shaft being independent from the motor shaft and said shafts being connected by a coupling. By application of the invention there is reached, that the pump shaft and the motor shaft need not be exactly aligned, whereas the bending loads on the suction end of the pump body and other bending forces due to hoi.sting and lowering the suction pipe and to the streaming of the water are not transmitted to the bearings of the pump shaft and the motor shaft, so that the life of these components is substantially enlarged. Furthermore this structure allows an easy and fast replacement of the worn out components. The invention will now be further elucidated referring to the accompanying drawing of an embodiment. Fig. 1 shows a longitudinal cross section of the dredge pump set according to the invention. Fig. 2 shows a plane view of the dredge pump set according to fig. 1. According to the drawing the dredge pump set comprises a dredge pump, which is generally indicated with 1, and a tubular carrier, which is generally indicated with 2. The dredge pump 1 has been provided with a volute body 3, in weich a suitable, rotating impeller 12 is arranged. At the inlet side a closing lid 4 is present, with a fastening flange 6, which can be fastened together with the end flange 37 of the tube 38 by means of (non shown) bolts to the edge flange 6 of the volute body 3. The closing lid 4 has also been provided with a tube end 7 having a fastening flange 8 for fastening the sucticn tube 9 of which only the end 15 shown. At the shaft side the volute body 3 has also been provided wit-h a fastening flange 10, for the edge flange 11 of the pump lid 13 and the end flange 14 of the tubular carrier 2. This tubular carrier consists of the bearing part 15, that is shown at the left side of the drawing and has a continuous,round diameter, and the motor part 16 that is shown at the right side of the drawing, that has at its end being connected to the bearing part 15 a round diameter and at its right outer end an oblong rounded form. On the impeller 12 the pump shaft 17 is fastened, said shaft extending through the pump lid 13 there having a shaft sealing 18, after which the pump shaft extends through the next shaft sealing 19 through a bearing body 20. In this bearing body 20 a number of bearings have been fastened, such as the cask bearings 21 and 22, at both sides of the bearing body 20, and the axial thrust bearing 23. The bearing body 20 has been fastened by means of the diametral supports 24 and 25 centrally inside the bearing part 15 of the tubular carrier 2. At the other end of the pump shaft 17 via the elastic coupling 16 the shaft 26 is fastened of the rotating hydraulic motor 27. This motor 27 is at its end turned away from the shaft side fastened to a motor support 28, which extends from the right, oblong rounded end flange 29 of the motor part 16 of the tubular carrier to the left side and is reinforced by means of the reinforcement plates 30. The pressure outlet tube end 31 of the volute body 3 carries a fastening flange 32, on which the pertaining -flange 33 is fastened of a bend piece 34 that is bent in two dimensions, whereas the other end flange 35 of this bend piece 34 lies in the same place vats, but at the upper side of the end flange 29 of the motor part 16 of the tubular carrier 2. The end flange 29 can be fastened to a carrying piece that is mounted as an extension of a (non shown) pressure tube line, whereas the end flange 35 can be fastened to a (non shown) reducer of this pressure line, of which the axis coincides with that of the motor 27, pump shaft 17 and impeller 12. Oblong rounded means two parallel sides witch half circles at the end. The invention is not limited to the shown and described embodiment but covers all variations thereof. Instead of a hydraulic motor also an electric or an air motor can be used or another prime mover. Although the dredge set according to the invention is in the first place intended for use in the towing or trailing suction tube of a dredge craft, it can also be applied in the submerged water suction line of a cutter head-suction dredge craft or on board of other dredge crafts.

Claims: CLAIMS 1. Dredge pump set for a dredge craft, comprising a tubular carrier for the pump set and the drive set that is connected to the pump shaft, in which the shaft side of the pump body is fastened to the one end of the tubular carrier in which the pump shaft and the drive set are housed, whereas the other end of the tubular carrier can be fastened to a support structure, which tubular carrier has been provided with at least one support element, that extends from the inner wall of the tubular carrier in an inward direction and has a bearing for the pump shaft and the drive set characterized in that the drive set comprises two or more bearings for the pump shaft, that are housed in a tubular bearing body of which the ends are sealed, whereas at least two support elements are fastened to the outside of the tubular bearing body, said pump shaft being independent from the motor shaft and said shafts being connected by a coupling. 2. The dredge pump set according to claim 1, characterized in that, the coupling being an elastic coupling. 3. The dredge pump set according to claims 1 or 2, characterized in that, the motor being fastened to a motor support, that is mounted at the end of the tubular carrier turned away from the pump body. 4. The dredge pump set according to claims 1-3, characterized in that, the closing flange at the shaft side of the pump body being fastened to a pertaining end flange of the tubular carrier. 5. The dredge pump set according to claims 1-4, characterized in that, the drive set having a hydraulic motor. 6. The dredge pump set according to claims 1-5, characterized in that, the drive set having an electric or an air motor or another prime mover. 7. The dredge pump set according to claims 1-6, characterized in that, the tubular carrier having at its end removed from the pump body an oblong rounded cross section. 8. The dredge pump set according to claims 1-7, characterized in that, the tubular carrier being fastened in the extension of the pressure tube of a trailing or towing suction installation, which pressure tube being fastened itself to a two dimensionally bent bend piece that extends from the outlet side of the pump to the upper side of the oblong rounded end of the tubular carrier. 9. The dredge pump set according to claims 1-8, characterized in that, the end of the bend piece lying in one plane with that of the tubular carrier.

Inventors: VAN DEE, NICOLAAS FRANS
Applicants: B.V. BEHEERMAATSCHAPPIJ  T. DEN BREEJEN VAN DEN BOUT
Application year: 1980
Main classification: F04D29
IPC codes: F04D29, E02F3