SRP 550
TABLE OF CONTENTS
Sec t i o n / Pag e
Ti t l e
1
/ 2
Technical Data
2
/ 3
Design and Construction
3
/ 11
Hydraulic Control System
4
/ 16
Power Transmission
5
/ 19
Clutch
6
/
Standard Installation Drawings
SRP 550
RUDDERPROPELLER FOR MAIN PROPULSION Power range 620 – 920 kW
TECHNICAL DATA Input speed range Other input speeds on request ! Max. input torque At service factor 1.0 Attention
Reduction
900 – 1000 rpm
< 1500 rpm
< 1800 rpm
9762 Nm
6508 Nm
5423 Nm
Torque limitations due to classification and to service factor are to be applied! Total
2.804 : 1
4.202 : 1
5.059 : 1
Upper gear
0.913 : 1
1.368 : 1
1.647 : 1
Lower gear
3.071 : 1
3.071 : 1
3.071 : 1
Rotation of input shaft Looking at input flange standard
clockwise
Propeller stem length (PAL) standard
2400 mm
Weight of standard SRP (inc. Propeller and oil)
7500 kg
SRP 550
DESIGN AND CONSTRUCTION
The SCHOTTEL Rudderpropeller type SRP 550 designed in the form of a Z - drive consists of the following three main assemblies (see drawing HDB2001): -
Upper gearing (2) with lubricating oil level tank (3) Steering pipe (14) with support tube (13) and Lower gearing (17) with propeller (16) and nozzle (15)
Anodes (18) are attached to the SRP to protect system against corrosion. Power transmission is accomplished from the drive flange/clutch (1) through the drive shaft to a set of helicoidal bevel gear. From there the propulsion is transmitted by the power transmission shaft, lower bevel gear set and propeller shaft to the propeller (16). The twin set of gears gives suitable reduction from input speed to propeller speed. Installation of a nozzle (15) is standard in order to increase thrust at low ship speeds. A unique design of the steering pipe (14) reduces the amount of work by the yard for installation of the unit.
Upper gearing (2) Housing: The housing is made of spheroidal graphite cast iron (GGG) of suitable quality and pressure-tested. It is topped by an expansion tank (3). Internal channels allow free flow of lubricant to the relevant spots. In order to reduce losses during operation the upper gear housing (2) is emptied of lub. oil thus the gear is operated in
SRP 550
DESIGN AND CONSTRUCTION
Hydraulic motors: Two hydraulic steering motors (7) of proven type are vertically mounted on the top-plate (11) and flanged onto a reduction planetary gear set (8) in order to achieve suitable rotating (steering) speed. Thrust direction transmitter: A separate output shaft, driven by the steering spur gear wheel is connected to a feedback transmitter (19) (electrical and mechanical), mounted onto the top-plate (11). Suitable reduction gives 1 : 1 synchronism with the lower gearbox (17).
Intermediate section Support tube (13): The stem section (14) is supported by a tube-shaped housing (13) which is the relevant part of construction for the hull’s framing. This solution eliminates all additional components like tapered thrust ring, machined trunk flange etc. It eliminates splitting of the Rudderpropeller unit during installation by mounting the complete unit from below into a corresponding hull opening and bolting it to the ship’s structure. For repair all relevant parts can easily be disassembled.
The large volume of the support tube is used as oil tank also providing a large submerged area ensuring sufficient lub-oil cooling by heat dissipation to the surrounded water. Steering pipe: Attached to the spur gear the stem section (14) is the vertical
SRP 550
DESIGN AND CONSTRUCTION
Propeller (16): The propeller is four- or five-bladed, depending on the results of the torsional vibration analysis. Standard propeller material is CuAlNi. Both rotating directions are possible. Nozzle (15): The nozzle is of modified Kort design, type 19A. It is made of mild steel (shipbuilding steel grade A), with stainless steel plating in the inner surface. Zinc anodes (18) in suitable size and quantity are welded to the outerplating. The Nozzle is dismountable.
LUBRICATION SYSTEM The SRP is lubricated by means of a combined splash/spray oil system. During standstill of the SRP, the oil level comes up to the topedge of the sight glass (5) of the lubricating oil level tank (3). During SRP OPERATION, the upper gearing (17) is drained through the topedge of the lubricating oil tank (3) providing spray oil during operation, accomplished through restricted supply bores and reducing splash losses in the upper gearing. In the lower section of the SRP, the lubricating oil is circulated by the oil helix. The lower gearing (17) and the steering spur gearing are splashlubricated. The lubricating oil is cooled in the lower section by the water surrounding the SRP. The steering planetary gears are sealed from the SRP and have a separate oil filling.
SRP 550
DESIGN AND CONSTRUCTION
SPARES Spares are supplied according to the requirements of the requested classification certificate for restricted or unrestricted service.
DOCUMENTATION -
General arrangement
-
Detailed specification (as in hand)
-
Technical drawings necessary for installation of SCHOTTEL components into the
vessel -
Operation and maintenance instructions (3 copies) in English (standard) language
-
Welding procedure manual (if required)
CLASSIFICATION Units will be supplied with certificate of the requested Classification Society.
SRP 550
DESIGN AND CONSTRUCTION
COATING AND PAINT STRUCTURE Preparation A) Rough areas: Sand blasted with a degree of purity SA 2 ½ , DIN 55928 acc. part 4, For casting maker’s and test instructions are observed. B) Primer areas Thoroughly residue – free cleaning with degreaser
Coating struc ture on iron casting and steel parts coming into contact wi th sea water Coating
Dried coating thickness
1 x 2 K Epoxy – resin –primer
abt. 40 µm
3 x 2 K Epoxy- resin abraision resistant coating system
abt 3 x 100 µm
SRP 550
HYDRAULIC CONTROL SYSTEM
HYDRAULIC STEERING SYSTEM SST-612 Functional description: The rudder position transmitter COPILOT 2000 gives the electric steering command via an electric circuit to the hydraulic power-pack. According to the preselected thrust direction the variable displacement pump follows up until the set position is reached and then switches to zero – delivery. The electric/hydraulic full follow-up (waydependable) steering system SST 612 is proportionally controlled, resulting in extremely smooth operation. The oil flow of the pump and thus the steering speed varies with the commanded change of azimuth travel; small changes give slow speed, greater changes give higher steering speed. The system features a specific soft shifting characteristic, even in case of high steering speeds. The system selects the shortest route. The feedback of the thrust direction is carried out electrically via a transmitter. This is mechanically driven by the spur wheel of the Rudderpropeller and transmits the thrust direction to the indicator unit, mounted on the steering column. The hydraulic power-pack of the system SST-612 comprises the following:
SRP 550
HYDRAULIC CONTROL SYSTEM
Technical data SST 612
Steering time for 180°
Pump drive electric
electric
380V / 50 Hz
440 / 60 Hz
approx 11 sec
approx 9 sec
Max. operating pressure
mechanical
approx. 10-12 sec
210 bar
Hy-tank , oil capacity
approx. 35 dm³
Hy – oil type
ISO VG 32 HLP (see recommended lubricants)
Max. oil flow per min
approx. 48 dm³
approx. 57 dm³
approx. 51 dm³
Revolutions of hy - pump
1450 r.p.m.
1750 r.p.m.
750 – 2520 r.p.m.
SRP 550
POWER TRANSMISSION
STANDARD STERN INSTALLATION (Long shaft l ine) Due to the relatively large distance between the engine output and SRP input in horizontal and vertical direction a combination of shafts (W-configuration) is required. At the flexible coupling mounted to the engine’s flywheel a short countershaft with two bearings and attached flange is arranged in order to support the engine crankshaft. A V- belt pulley may be mounted on the aft end of this shaft to drive a hydraulic pump mechanically. Via a combination of two cardan shafts, and one solid intermediate shaft the power is transmitted to the pneumatically operated disengaging clutch K-550 directly mounted on the input flange of the Rudderpropeller. The solid shaft is fitted with a suitable number of plummer blocks and both ends of the shaft are equipped with flanges matching the required type of cardan shaft. In critical installation situations with a large distance in height and a short longitudinal distance between the SRP and the engine, the Rudderpropeller as well as the engine may be installed with a declination angle (up to 5°) in order to reduce the bending angle of the cardan shafts, which should not exceed 8°. The input shaft of the SRP and the engine crankshaft have to be parallel in any plane. To ensure a vibration-free installation and to ease the shipyard’s alignment procedure SCHOTTEL will carry out a pointer calculation and provide a pointer drawing to the shipyard. The pointers are not SCHOTTEL supply. For installation of shafting the installation instructions are to be observed. The layout of the shafting is based upon the following information to be confirmed by the
SRP 550
TECHNICAL DATA SHEET Electric – pneumatic clutch type K - 550
DESCRIPTION: The SCHOTTEL clutch, type K-550, is an electro-pneumatically operated clutch, specially designed for marine service and soft engagement. It is provided for engaging and disengaging of the Rudderpropeller from the prime mover. The clutch can be engaged while the engine is running at low speed and disengaged under all working conditions. The clutch is normally fitted directly to the input shaft of the Rudderpropeller. Internal maintenance-free bearings locate the inner end outer parts of the clutch axially and radially. A cardan shaft can be connected without any additional support shaft or bearing. The clutch mainly consists of the inner part with drum and input flange connection as well as support bearings, the outer part with friction shoes, pneus and output shaft connection and the electro-pneumatic control box. The clutch is engaged by air pressure. The friction shoes move radially in and out to engage and disengage. A heavy tireless tube behind the friction shoes expands under pressure causing the friction shoes to move inwards to engage the drum. The rate engagement is easily controlled by regulating the rate of air flow into the tube. The tube is designed to expand as friction wear occurs, automatically adjusting for wear. Exhausting of air and low-stress leaf springs ensure disengagement under all
SRP 550
TECHNICAL DATA SHEET Electric – pneumatic clutch type K - 550
TECHNICAL DATA Version 1
Version 2
Version 3
Max. input power
828 kW
920 kW
920 kW
Max. input speed
900 r.p.m.
1000 r.p.m.
1800 r.p.m.
Max. input torque
9762 Nm
9762 Nm
5423 Nm
Max. engaging speed
500 r.p.m.
500 r.p.m.
900 r.p.m.
Shipping torque at the air pressure of 9 bar
17303 Nm
16633 Nm
8825 Nm
Max. engaging torque at the are pressure of 9 bar
13842 Nm
13306 Nm
7060 Nm
