A longitudinal vibration damping device and method for a long shafting system of a ship

Abstract

The present invention provides a longitudinal vibration damping device for a ship's long shafting system, which includes a longitudinal shafting vibration damper and a vibration damper base. The ship's long shafting passes through the longitudinal shafting vibration damper, and the moving part on the longitudinal shafting vibration damper is installed in interference fit with the ship's long shafting. The longitudinal shafting vibration damper is fixed on the vibration damper base, and the outer side wall of the vibration damper base is connected to the hull structure. The present invention also relates to a method for longitudinal vibration damping of the ship's long shafting system using the longitudinal vibration damping device for the ship's long shafting system. The longitudinal vibration damping device for the ship's long shafting system of the present invention can be used as a remedial measure for longitudinal shafting vibration damping after the ship is built, and can also be used as a preventive measure during the ship design process, improving the shafting stability and extending the service life. Compared with other solutions, it has a relatively small cost and good effect.

Description

Technical Field

[0001] The present invention belongs to the technical field of ship production, and particularly relates to a longitudinal vibration damping device and a vibration damping method for a long ship shafting system. Background Art

[0002] In the construction of civil ships, a design with a long shafting system for the propulsion system often appears. The length of the shafting system can reach 50m or more. The longer the shafting system, the more serious the longitudinal vibration will be, which affects the stability of the shafting system and reduces the service life of the shafting system. Due to limited conditions during the design process, it is impossible to accurately predict, and it is difficult to detect during the design stage. The longitudinal vibration phenomenon often appears during the sea trial after the ship is built, especially the longitudinal vibration of the long shafting system. There are many factors causing the vibration of the shafting system, the causes are complex, the solutions are complex and diverse, and the cost is high. Summary of the Invention

[0003] In view of the above problems, the present invention provides a longitudinal vibration damping device and a vibration damping method for a long ship shafting system, which can be used as a remedial measure for longitudinal vibration damping of the shafting system after the ship is built, and can also be used as a preventive measure during the ship design process, improving the stability of the shafting system and extending the service life. Compared with other solutions, the cost is relatively small and the effect is good.

[0004] To achieve the above object, the present invention adopts the following technical solutions: A longitudinal vibration damping device for a long ship shafting system includes a shafting longitudinal shock absorber and a shock absorber base. The long ship shafting system passes through the shafting longitudinal shock absorber. The moving part on the shafting longitudinal shock absorber is installed in interference fit with the long ship shafting system. The shafting longitudinal shock absorber is fixed on the shock absorber base, and the outer side wall of the shock absorber base is connected to the hull structure.

[0005] Further, the shock absorber base includes a U-shaped support piece connected to the hull structure. On the inner side wall of the U-shaped support piece, there is a U-shaped fixing plate for fixing the shafting longitudinal shock absorber. The outer side wall of the U-shaped fixing plate is perpendicular to the inner side wall of the U-shaped support piece. On the U-shaped fixing plate, there are a plurality of first screw holes for fixing the shafting longitudinal shock absorber. The plurality of first screw holes are distributed in a U shape around the U-shaped groove of the U-shaped fixing plate. On the shafting longitudinal shock absorber, there are a plurality of second screw holes corresponding to the first screw holes on the U-shaped fixing plate. The shafting longitudinal shock absorber is located inside the U-shaped support piece and is fixed on the shafting longitudinal shock absorber installation fitting surface of the U-shaped fixing plate by bolts passing through the screw holes.

[0006] Further, the shafting longitudinal shock absorber installation fitting surface is the side surface of the U-shaped fixing plate close to the stern of the ship.

[0007] Further, on the side surface of the U-shaped fixing plate close to the bow of the ship, there is a U-shaped hull reinforcing rib. The U-shaped hull reinforcing rib is arranged parallel and spaced from the U-shaped support piece. The plurality of first screw holes are located on the side of the U-shaped hull reinforcing rib away from the U-shaped support piece.

[0008] Further, a plurality of transverse hull stiffeners are provided between the U-shaped support piece and the U-shaped hull stiffener, and the plurality of transverse hull stiffeners are arranged relatively with respect to the vertical central axis of the shock absorber seat.

[0009] Further, the U-shaped support piece includes a flat portion at the bottom and curved portions arranged oppositely with respect to the flat portion.

[0010] Further, the device further includes two drain collection covers. A plurality of drain collection cover mounting holes with central axes parallel to the ship length direction are evenly distributed on the longitudinal shafting shock absorber. The drain collection cover mounting holes penetrate through both side surfaces of the longitudinal shafting shock absorber. The plurality of drain collection cover mounting holes are located inside the second screw holes. The two drain collection covers are respectively connected to the front and rear side surfaces of the longitudinal shafting shock absorber through bolts passing through the drain collection cover mounting holes. The ship shafting passes through the two drain collection covers; Drain pipes communicating with their interiors are connected to both drain collection covers.

[0011] Further, a drain hole for the drain pipe to pass through is provided between the U-shaped support piece and the U-shaped hull stiffener, and the vertical central axis of the drain hole coincides with the vertical central axis of the U-shaped hull stiffener.

[0012] A method for longitudinally damping the long shafting of a ship using the above-mentioned longitudinal shafting damping device for a ship.

[0013] For the longitudinal shafting damping device of the ship of the present invention, the longitudinal shafting shock absorber is fixed to the shock absorber seat and is installed on the shafting by interference fit. The shock absorber base is connected to the hull structure. The longitudinal shafting shock absorber bears the longitudinal exciting force of the shafting, and distributes the exciting force to the hull structure through the shock absorber base, thereby reducing the longitudinal vibration of the shafting. The damping effect is between 30% and 70%; the stability of the shafting is improved and the service life is extended. Compared with other solutions, the cost is relatively small and the effect is good; the internal structure of the longitudinal shafting shock absorber of the present invention is the same as that of the shafting shock absorber used on the main engine crankshaft, and the shape, part size and the size of the shafting through hole are adaptively adjusted according to the ship shafting and are matched with the ship shafting. The installation position of the longitudinal shafting damping device of the ship of the present invention on the ship shafting is finally comprehensively considered and preferably a position far from the main engine in combination with the shafting layout diagram, the hull structure and the vibration calculation.

[0014] Shafting vibration includes torsional vibration, longitudinal vibration, whirling vibration, coupled vibration, etc. During the ship design process, shafting vibration is analyzed and calculated based on ship structure, shafting design, shafting layout, main engine characteristics, etc. If it is found that there is a possibility of excessive shafting vibration, the longitudinal vibration damping device for the long shafting of the ship in the present invention can be directly analyzed and calculated as a damping design without changing the hull structure. It is carried out along with the ship design and construction. The longitudinal vibration damper of the shafting in the present invention is divided into two semi-circular structures, so that the longitudinal vibration damper can be installed directly on the shaft without removing the shaft, and any design and original layout of the already installed shafting do not need to be changed, such as shaft diameter, flange, bearing and pedestal, and the shafting does not need to be disassembled and assembled, etc. Only the longitudinal vibration damper of the shafting is installed on the shaft under the existing conditions, and then the structure is strengthened on the original hull structure to bear and distribute the exciting force of the longitudinal vibration damper, which can be used as a remedial measure for longitudinal vibration damping of the shafting after the ship is built; in addition to having a damping effect in the longitudinal direction, it also has an obvious damping effect in other directions.

[0015] Because the longitudinal vibration damper of the shafting requires lubricating oil to play a role in lubrication and hydraulic pressure bearing between the rotating parts and the fixed parts, an external lubricating oil system needs to be supplied; the lubricating oil system can share the lubricating oil system of the main engine, adding a branch to the original lubricating oil system of the main engine, and the pressure is basically the same as that of the lubricating oil system of the main engine. An independent lubricating oil system can also be set up; it can be selected by the user according to his own situation; there is a certain gap between the moving parts and the fixed parts of the longitudinal vibration damper, which is filled with lubricating oil with a certain pressure to transmit the exciting force. The size of the gap is related to the length of the shafting and the longitudinal displacement. It is appropriately larger than the longitudinal displacement, generally less than 20 mm. The specific value can be designed by the supplier such as MAN B&W according to the shafting layout. For the completed ship, it can be obtained through actual measurement to prevent physical contact between the moving parts and the fixed parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a perspective view of the use state of the longitudinal vibration damping device for the long shafting of the ship described in the present invention;

[0017] Figure 2 is a longitudinal sectional view of the use state of the longitudinal vibration damping device for the long shafting of the ship described in the present invention;

[0018] Figure 3 is a schematic perspective structure of the damper pedestal described in the present invention Figure 1 ;

[0019] Figure 4 is a schematic perspective structure of the damper pedestal described in the present invention Figure 2 .

[0020] Among them, 1 - shock absorber base, 2 - longitudinal shafting shock absorber, 3 - ship shafting, 4 - drain collection cover, 5 - drain pipe, 11 - U-shaped support piece, 12 - U-shaped fixing plate, 13 - U-shaped hull reinforcing rib, 14 - transverse hull reinforcing rib, 15 - drain hole, 121 - first screw hole, 21 - second screw hole, 111 - straight part, 112 - bent part. Specific implementation mode

[0021] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0022] The longitudinal shafting shock absorber in this embodiment is transformed from the longitudinal shock absorber AVD (Axial Vibration Damper) used in the S40 series models of MAN-B&W. The internal structure is the same, only the appearance, part dimensions, and the size of the shafting through holes are different. The lubricating oil system has been adaptively adjusted according to the ship shafting and is matched with the ship shafting.

[0023] As Figures 1 - 4 shown, a longitudinal shock absorption device for a long ship shafting includes a longitudinal shafting shock absorber 2 and a shock absorber base 1. The longitudinal shafting shock absorber 2 is fixed on the shock absorber base 1. The ship shafting 3 passes through the longitudinal shafting shock absorber. The longitudinal shafting shock absorber 2 and the ship shafting 3 are fixedly installed on the moving parts that rotate with the shaft on the shaft by interference fit. The fixing parts are connected to the shock absorber base. The outer side wall of the shock absorber base 1 is connected to the hull structure; the shock absorber base 1 includes a U-shaped support piece 11 connected to the hull structure. On the inner side wall of the U-shaped support piece 11, there is a U-shaped fixing plate 12 for fixing the longitudinal shafting shock absorber 2. The outer side wall of the U-shaped fixing plate 12 is perpendicular to the inner side wall of the U-shaped support piece 11. On the U-shaped fixing plate 12, there are a plurality of first screw holes 121 for fixing the longitudinal shafting shock absorber 2. The plurality of first screw holes 121 are distributed in a U-shape around the U-shaped groove of the U-shaped fixing plate 12. On the longitudinal shafting shock absorber 2, there are a plurality of second screw holes 21 opposite to the first screw holes 121 on the U-shaped fixing plate 12. The longitudinal shafting shock absorber 2 is located inside the U-shaped support piece 11 and is fixed to the installation fitting surface of the longitudinal shafting shock absorber on the U-shaped fixing plate 12 by bolts passing through the first screw holes 121 and the second screw holes 21. The installation fitting surface of the longitudinal shafting shock absorber is the side surface of the U-shaped fixing plate 12 close to the stern of the ship; on the side surface of the U-shaped fixing plate 12 close to the bow of the ship, there is a U-shaped hull reinforcing rib 13. The U-shaped hull reinforcing rib 13 is arranged in parallel and spaced from the U-shaped support piece 11. The plurality of first screw holes 121 are located inside the U-shaped hull reinforcing rib 13; between the U-shaped support piece 11 and the U-shaped hull reinforcing rib 13, there are a plurality of transverse hull reinforcing ribs 14. The plurality of transverse hull reinforcing ribs 14 are arranged opposite to the vertical central axis of the shock absorber base 1; the U-shaped support piece 11 includes a straight part 111 at the bottom and bent parts 112 arranged opposite to the straight part 111.

[0024] The device further includes two discharge and collection covers 4. A plurality of discharge and collection cover mounting holes 22 with central axes parallel to the ship length direction are evenly distributed on the shafting longitudinal shock absorber 2. The discharge and collection cover mounting holes 22 penetrate through both side surfaces of the shafting longitudinal shock absorber 2. The plurality of discharge and collection cover mounting holes 22 are located inside the second screw holes 21. The two discharge and collection covers 4 are respectively connected to the front and rear side surfaces of the shafting longitudinal shock absorber 2 through bolts passing through the discharge and collection cover mounting holes 22. The ship shafting passes through the two discharge and collection covers 4. Discharge pipes 5 communicated with their interiors are connected to the two discharge and collection covers 4. A discharge hole 15 for the discharge pipe 5 to pass through is provided between the U-shaped support piece 11 and the hull U-shaped stiffener 13. The vertical central axis of the discharge hole 15 coincides with the vertical central axis of the hull U-shaped stiffener 13.

[0025] For the method of longitudinally damping the long ship shafting by using the above longitudinal damping device for long ship shafting, the damping effect is shown in the following table.

[0026] Table 1

[0027]

[0028] Those of ordinary skill in the art should understand that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A longitudinal vibration damping device for a ship's long shafting, characterized in that, It includes a longitudinal vibration damper for the shafting system and a vibration damper base. The long shafting system of the ship passes through the longitudinal vibration damper for the shafting system. The longitudinal vibration damper for the shafting system is installed with an interference fit with the long shafting system of the ship. The longitudinal vibration damper for the shafting system is fixed on the vibration damper base. The outer side wall of the vibration damper base is connected to the hull structure. The vibration damper base includes a U-shaped support piece connected to the hull structure. On the inner side wall of the U-shaped support piece, there is a U-shaped fixing plate for fixing the longitudinal vibration damper for the shafting system. The outer side wall of the U-shaped fixing plate is perpendicular to the inner side wall of the U-shaped support piece. On the U-shaped fixing plate, there are multiple first screw holes for fixing the longitudinal vibration damper for the shafting system. The multiple first screw holes are distributed in a U-shape around the U-shaped groove of the U-shaped fixing plate. On the longitudinal vibration damper for the shafting system, there are multiple second screw holes opposite to the first screw holes on the U-shaped fixing plate. The longitudinal vibration damper for the shafting system is located inside the U-shaped support piece and is fixed on the installation and fitting surface of the U-shaped fixing plate through bolts passing through the screw holes. The installation and fitting surface of the longitudinal vibration damper for the shafting system is the side surface of the U-shaped fixing plate close to the stern of the ship. On the side surface of the U-shaped fixing plate close to the bow of the ship, there is a U-shaped hull reinforcing rib. The U-shaped hull reinforcing rib is arranged parallel and at intervals to the U-shaped support piece. The multiple first screw holes are located on the side of the U-shaped hull reinforcing rib away from the U-shaped support piece. Between the U-shaped support piece and the U-shaped hull reinforcing rib, there are multiple hull transverse reinforcing ribs. The multiple hull transverse reinforcing ribs are arranged symmetrically with respect to the vertical central axis of the vibration damper base. The U-shaped support piece includes a flat part at the bottom and curved parts arranged oppositely with respect to the flat part.

2. The longitudinal vibration damping device for the long shaft system of a ship according to claim 1, characterized in that, The device further includes two drain and collection covers. On the longitudinal vibration damper for the shafting system, there are multiple drain and collection cover mounting holes with central axes parallel to the length direction of the ship. The drain and collection cover mounting holes penetrate through both side surfaces of the longitudinal vibration damper for the shafting system. The multiple drain and collection cover mounting holes are located inside the second screw holes. The two drain and collection covers are respectively connected to the front and rear side surfaces of the longitudinal vibration damper for the shafting system through bolts passing through the drain and collection cover mounting holes. The ship shafting system passes through the two drain and collection covers. On the two drain and collection covers, there are drain pipes connected to their interiors.

3. The longitudinal vibration damping device for the long shaft system of a ship according to claim 2, characterized in that, Between the U-shaped support piece and the U-shaped hull reinforcing rib, there is a drain hole for the drain pipe to pass through. The vertical central axis of the drain hole coincides with the vertical central axis of the U-shaped hull reinforcing rib.

4. A method for longitudinally damping the long shafting system of a ship using the longitudinal vibration damping device for the long shafting system of a ship according to any one of claims 1 to 3.

Images