DEVICE FOR RAISING A RUDDER STOCK ON A SHIP

Description

Description

[0001] The present invention regards a device, and a method for raising a rudder stock on a ship, as an integrated part of the ships steering engine with the purpose of performing maintenance on the internal wearing parts of the steering engine.

Background of the invention and prior art

[0002] The purpose of the invention is to do necessary maintenance work on steering engines, more specifically "rotary vane"- steering engine (hereinafter referred to as steering engine), which are considerably easier then current practise. A representative steering engine contains the entire upper radial bearing of the rudder system and rudder radial bearing. A rudder stock on a ship is normally fasted radially at 2, 3 or 4 points and axially at one point, of which the steering engine can be the axial bearing point - also called rudder axial bearing. During maintenance of / or faults on the steering engine it must be feasible to lock the rudder stock both radially and axially, there are available two alternative methods for locking the rudder stock. Method 1, in which the rudder and the rudder stock are secured by chains or cables that normally are fastened to the rudder blade itself: and Method 2, in which the rudder stock is secured by use of equipment mountable directly around the rudder stock during installation of the steering engine at the building yard. Furthermore, there a need in the field to relieve the rudder stock so that it can be replaced.

[0003] Of prior art in the field an example is disclosed in NO 302695 B1 that comprises a locking device that may be activated to maintain a rudder stock axially and radially relative to the structure of the ship in connection with replacement or maintenance of a steering engine of a ship.

[0004] Other prior arts in the field are GB 1409245 A and JP 58008496 A that discloses other rudder systems compared to the present invention.

[0005] A further prior art example is EP 1 437 296.

[0006] The disadvantages with the prior art is that there are no easy solutions to raise the rudder stock for relieving the rudder axial bearing in a steering engine so that it may easily be replaced.

[0007] Method 1 requires resource-demanding operations, both cost-wise, time-wise and personnel wise. Furthermore, it is assumed that the ship is situated in port or is located in calm waters.

[0008] Method 2 can be split in two different variants 2a and 2b. Method 2a is a solution wherein a locking device is mounted on the deck of the ship. Method 2b is a solution wherein a locking device is mounted on the underside of the steering engine. Method 2 solves many of the disadvantages of method 1. However, method 2 is able to lock only radially and axially. It is not possible to raise the rudder stock so that the rudder axial bearing is relieved and thereby replaceable.

[0009] In order to raise rotor, rudder and rudder stock so that the rudder axial bearing and other wearable parts is relieved/unloaded and may be replaced supplementary equipment and extra anchor points for these are required, that again is resource-demanding, time-wise as well as cost-wise.

[0010] The object of the present invention is therefore to find a device that ease the work of raising of the rudder stock, rudder and rotor from the rudder axial bearing itself so that the wearable parts can be replaced in an easier way compared to current methods. This object is achieved by a top cover according to claim 1.

[0011] The present invention will further be described in detail in connection with some embodiments and with reference to drawings, wherein figure 1 shows a schematic sketch of a rotary-vane steering engine according to the invention, cross-sectioned and in side view; figure 2 is a section of details A in figure 1, and fig 3 is a section of details B in fig 1.

Detailed description

[0012] The device shown in fig 1 is symmetrical around the centre of the rotor. Exceptions are detail A and detail B. Consequently, equal parts arc numbered on one of the sides only.

[0013] In figs 1 to 3 an arrangement 1 is shown on an upper part of a rudder stock 2, of which the upper part is equipped with a steering engine attached to the hull 3 of the ship. The steering engine comprises a rotor housing 4, a rotor 5 connected to the rudder stock, a top cover 6, a bottom cover 7, a hydraulic nut 8 with removably mounted retaining ring 9, and a hydraulic cylinder 10.

[0014] The hydraulic cylinder 10 is attached to the top cover 6 using a fastening- / adjusting device 11. Furthermore, the hydraulic cylinder 10 is equipped with a hydraulic piston 12 receiving a hydraulic pressure on one side through a supply channel 13 connected to a manual pump or a hydraulic system / power source (not shown).

[0015] The at least one upper radial bearing of the rudder stock 2 is located in the steering engine and is here represented by a radial bearing 14 in the top cover and a radial bearing 15 in the bottom cover. In this embodiment a rudder axial bearing 16 is located in the bottom cover 7.

[0016] During normal operation of the steering engine all the weight of the rudder and the rudder stock is resting on the rudder axial bearing 16 since there is not much free space between the retaining ring 9 and the hydraulic cylinder 10. To be able to change the rudder axial bearing 16, radial bearing 15 or other wearing parts in the bottom cover it is necessary to raise the rudder stock so that the force on the bottom cover is removed. If not it will be difficult to loosen the securing screws holding the bottom cover 7 and the rotor housing 4 together due to the large force that the rotor, rudder stock and the rudder exerts.

[0017] To relieve the rudder axial bearing 16 the rudderstock and the rudder must be sufficiently lifted so that the force exerted on the rudder axial bearing is removed. Relevant lifting height of the rudder and rudder axial bearing is in this context only a few tenths of a millimetre since the bottom cover 7 and rudder axial bearing 16 will be moved down and away from the contact surface of the rudder stock 2.

[0018] The hydraulic nut 8 is mounted on top of the rudder stock 2 and is locked so that there are no relative motions between the nut 8, rotor 4 and rudder stock 2. During normal operation of the rudder there are a small clearance between the retaining ring 9 on the hydraulic nut and the hydraulic cylinder 10. In order to lift the rudder stock 2 it is necessary to lift the hydraulic cylinder, and the fastener- /adjusting devices 11 are loosened to allow for this.

[0019] By applying pressure on the hydraulic piston 12 through the supply channel 13 the hydraulic cylinder 10 must be raised and collided with the retaining ring 9 on the hydraulic nut 8. The hydraulic cylinder would then raise rotor 4, rudder and rudder stock 2 to the desired position, about 0,5-1,0 mm. The reactive power from rotor, rudder stuck and rudder is then transferred from the bottom cover 7 to the rotor housing 4 and further to the hull of the ship. The vertical position is maintained by maintaining the pressure in the supply channel 13 until bottom cover 7 is detached from the rotor housing. Afterward the pressure in the supply channel 13 is reduced, after which the cylinder will be brought down to the top of the top cover 6.

[0020] Subsequent to carrying out necessary repairs the supply channel 13 is pressurised so that the rudder stock 2 is raised and the bottom cover 7 can be remounted in place. When the pressure finally is released from the supply channel 13 the hydraulic cylinder 10 will once again be brought down on top of the top cover 6, and the weight of the rotor, rudder stock and rudder will again be brought down on the rudder axial bearing. The operation is ended by tightening up the fastening- / adjusting devices so that the hydraulic cylinder 10 is fastened to the cover.

Claims

1. Top cover for a steering engine to raise a rudder stock on a ship to relieve a rudder axial bearing, the steering engine being fastened to the rudder stock (2) using a hydraulic nut (8) and further being connected to a structure of the ship (3), characterized in that the top cover (6) has an hydraulic cylinder (10) attached to it, the hydraulic cylinder being arranged to raise and engage the hydraulic nut (8), thus raising the rudder stock (2), wherein the hydraulic cylinder further comprises

- a hydraulic piston (12),

- at least one supply channel (13) for hydraulic oil, and

- at least one fastening/adjusting device (11).

2. Top cover according to claim 1, characterized in that the hydraulic nut (8) is equipped with a retaining ring (9) on which the hydraulic cylinder (10) can be abutted.

3. Top cover according to claim 2, characterized in that the retaining ring (9) is divided so that it is detachable and easy to remove from the hydraulic nut (8).

4. Method for using a top cover according to claims 1-3 for raising a rudder stock (2) on a ship so that the rudder axial bearing (16) is relieved, and wherein the rudder stock (2) is equipped with a steering engine fastened to the rudder stock using a hydraulic nut (8) and further connected to with the structure of the ship (3), characterized in that

(a) loosening the at least one fastening-/adjusting device (11),

(b) connecting /supplying oil to the supply channel (13),

(c) increasing the pressure so that the hydraulic piston (12) abuts the top cover (6) and continuing until the hydraulic cylinder (10) abuts the retaining ring (9) and raises rotor (5), rudder stock (2) and rudder by around 0.5-1.0 mm,

(d) loosening the bottom cover (7),

(e) reducing the pressure in the supply channel (13) until the hydraulic cylinder (10) again abuts the top cover (7) so that the entire rudder arrangement rest on the top cover (6) via the retaining ring (9),

(f) executing necessary maintenance of wearing parts in the bottom cover (7),

(g) repeating point (c),

(h) fastening the bottom cover (7).

Ansprüche

1. Oberer Deckel für eine Rudermaschine zum Anheben eines Ruderschaftes auf einem Schiff um ein Achsiallager des Ruders entlasten, wobei die Rudermaschine am Ruderschaft (2) befestigt ist unter Verwendung einer hydraulischen Mutter (8) und ferner mit einer Schiffsstruktur (3) verbundenen ist, dadurch gekennzeichnet, dass an den oberen Deckel (6) ein Hydraulikzylinder (10) befestigt ist und ein integrierter Teil der der Rudermaschine ist, wobei der Hydraulikzylinder zum Anheben und mit der hydraulischen Mutter (8) in Eingriff zu kommen angeordnet ist, um damit den Ruderschaft (2) anzuheben wobei der Hydraulikzylinder weiterhin umfasst

- einer hydraulischen Kolben (12),

- wenigstens einen Versorgungskanal (13) für Hydrauliköl, und

- wenigstens eine Befestigungs-/Einstellungseinrichtung (11).

2. Oberer Deckel gemäß Anspruch 1, dadurch gekennzeichnet, dass die hydraulische Mutter (8) mit einem Haltering (9) ausgerüstet ist auf welchen der Hydraulikzylinder (10) abgestützt werden kann.

3. Oberer Deckel gemäß Anspruch 2, dadurch gekennzeichnet, dass der Haltering (9) geteilt ist so dass er abnehmbar und einfach von der hydraulischen Mutter (8) zu entfernen ist.

4. Verfahren zur Verwendung eines oberen Deckels gemäß den Ansprüchen 1-3 zum Anheben eines Ruderschaftes (2) auf einem Schiff so dass das Achsiallager des Ruders (16) entlastet ist, und wobei der Ruderschaft (2) ausgerüstet ist mit einer Rudermaschine befestigt am Ruderschaft unter Verwendung einer hydraulischen Mutter (8) und ferner verbundenen mit der Schiffsstruktur (3), gekennzeichnet durch

(a) lockern der wenigstens einen Befestigungs-/Einstellungseinrichtung (11),

(b) anschließen/zuführen von Öl an den Versorgungskanal (13),

(c) erhöhen des Drucks so dass der hydraulische Kolben (12) anstößt an den oberen Deckel (6) und fortsetzen bis der Hydraulikzylinder (10) anstößt an den Haltering (9), und Rotor (5), Ruderschaft (2) und Ruder um circa 0.5-1.0 mm anhebt,

(d) lockern des Bodendeckels (7),

(e) reduzieren des Drucks im Versorgungskanal (13) bis der Hydraulikzylinder (10) wiederum an den oberen Deckel anstößt (7), so dass das gesamte Rudersystem auf dem oberen Deckel (6) über den Haltering (9) ruht.

(f) durchführen von erforderlicher Wartung von Verbrauchsteilen im Bodendeckel (7),

(g) wiederholen von Punkt (c),

(h) befestigen des Bodendeckels (7),

(i) befestigen der wenigstens einen Befestigungs-/Einstellungseinrichtung (11).

Revendications

1. Couvercle supérieur pour un moteur de direction pour soulever une mèche de gouvernail sur un navire pour soulager un palier axial du gouvernail, le moteur de direction étant fixée à la mèche de gouvernail (2) utilisant un écrou hydraulique (8) et étant en outre connecté à une structure du navire (3), caractérisé en ce que le couvercle supérieur (6) comprend un cylindre hydraulique (10) qui s'y rattachent, le cylindre hydraulique étant agencé pour soulever et engager le écrou hydraulique (8), ainsi soulever la mèche de gouvernail (2), dans lequel le cylindre hydraulique comprend en outre

- un piston hydraulique (12),

- au moins un canal d'alimentation (13) pour l'huile hydraulique, et

- au moins un dispositif de fixation/réglage (11).

2. Couvercle supérieur selon la revendication 1, caractérisé en ce que le écrou hydraulique (8) est équipé d'un anneau de retenue (9) sur lequel le cylindre hydraulique (10) peut être aboute.

3. Couvercle supérieur selon la revendication 2, caractérisé en ce que le anneau de retenue (9) est divisé de sorte qu'il est amovible et facile à retire de l'écrou hydraulique (8).

4. Method pour utiliser un couvercle supérieur selon la revendications 1-3 pour soulever une mèche de gouvernail (2) sur un navire de sorte que le palier axial du gouvernail (16) est relevée, et dans lequel la mèche de gouvernail (2) est équipé d'un moteur de direction fixée à la mèche de gouvernail utilisant un écrou hydraulique (8) et en outre connecté à la structure du navire (3), caractérisé en ce que

(a) desserrage d'au moins un dispositif de fixation/réglage (11),

(b) connecter /fournir huile to the canal d'alimentation (13),

(c) augmenter la pression de sorte que le piston hydraulique (12) abute le couvercle supérieur (6) et continue jusqu'à le cylindre hydraulique (10) abute le anneau de retenue (9) et soulève rotor (5), mèche de gouvernail (2) et gouvernail de l'ordre de 0.5-1.0 mm,

(d) desserrage le couvercle inférieur (7),

(e) réduire la pression dans le canal d'alimentation (13) jusqu'à le cylindre hydraulique (10) aboute à nouveau le couvercle supérieur (7) de sorte que tout l'ensemble gouvernail reste sur le couvercle supérieur (6) par le anneau de retenue (9),

(f) exécuter entretien nécessaire des pièces d'usure dans le couvercle inférieur (7),

(g) répéter de point (c),

(h) fixée le couvercle inférieur (7).

Drawing