…..TTS, together with our partner Bosch Rexroth (BR), offers an advanced and modern shiplift and transfer system for ship repair, naval and new building shipyards.These state-of-the-art systems have demonstrated performance over many years.Each delivery is tailored to suit the individual yard’s demands. Our engineers cooperate with yard planners and civil engineers during the design process to reduce over allinvestment cost.
…..A shiplift minimises space requirements at the waterfront. The system can be designed for side or longitudinal transfer of ships. When combined with a transfer system, multiple work berths provide efﬁcient and environmentally safe work areas well away from the water.
…..A shiplift is designed to enable yards to launch and retrieve ships in a time-efﬁcient and controlled manner. By utilising various types of hoist capacities and varying their spacing, different demands are met with regard to maximum distributed load (MDL), total lifting capacity and platform size. All platform winches are monitored by an advanced control system,which ensures load distribution within the design limits during operation.
The Ship Rail Transfer System (STS)is designed to transport ships between a shiplift and dry berth on land. The ship is docked on a set of trestles with blocking and lifted by the transfer trolleys. The hydraulic lifting cylinders on the Transfer Trolleys are connected to form a ﬂuid bed. This means that the impact forces will be distributed during operation.There will be no high peak loads due to e.g. large overhang of the vessel’s bow or stern, in case of uneven blocking or with non-level rails. The operator will know exactly which forces exerted on the ship/block, and ground, at any time.
The ﬂuid bed may also be used during launching or lifting of the ships. The trestles will be positioned on the platform while the trolleys remain as ﬂuid bed support for the trestles. The Transfer Trolleys are designed to withstand submersion and can be safely left on the platform when submerged.
The system is module-based and can be built to accommodate various tasks, and can be delivered with alignment features for block assembly if necessary. Systems with up to 30,000-ton capacity has been delivered.
Some system advantages:
- Time efﬁcient launch and retrieval of vessels
- Efﬁ cient space utilization at the waterfront
- Full control of the forces in the system, both to the
ground and to the hull
- Gentle handling of the ship’s hull
- Rigid platform with trim and list feature
- Drum hoists with variable speed
- Longitudinal and/or transverse transfer
- Soft start and stop
- Double brake system
- Maximum torque at zero speed
- Transfer System with ﬂuid bed technology can operate safely on the soil settlement above 12 mm. Piling can be avoided.
- Several trestle sets can be served by one set of transfer trolleys
- Ship supported in either “ﬂoating mode” or in “spring mode”
- Self-propelled Transfer Trolleys, no transfer tow vehicles required
- Transfer system with block positioning units is suitable for block assembly
2. GENERAL DESCRIPTION
2 – 1 SHIPLIFT
GENERAL DESCRIPTION FOR INFORMATION ONLY. ALL PICTURES AND SKETCHES FOR ILLUSTRATION ONLY, NOT NECESSARILY
IDENTICAL TO OFFERED SYSTEM.FOR TECHNICAL DETAILS PLEASE REFER TO CHAPTER 3, “TECHNICAL SPECIFICATION AND
REQUIREMENTS”. FOR SCOPE OF SUPPLY PLEASE REFER TO CHAPTER 4, “SCOPE OF SUPPLY”.
The shiplift consists of a steel structural platform tha is lifted/lowered by a number of winches in a controlled and safe way. The platform of the shiplift is of rigid design, as this gives the shipyard several beneﬁ ts. The longitudinal stiffness of the platform enables the load to be distributed between several winches The control system ensures that this load levelling characteristic is within the design criteria. The platform can be listed and trimmed to accommodate vessels with a special hull form or vessels with an exceptional trim.
The Shiplift System mainly consists of:
2-1.1 Platform assembly
2-1.2 Winch assembly
2-1.3 Control system
2 – 1.1 Platform assembly
The Shiplift platform assembly consists of the following modules:
- Platform structure
- Transition rail
- Locking bar assembly (NB: optional)
- Lateral/longitudinal guiding structures or
- Grease lubrication system
The platform steel structure
contains of longitudinal and transverse beams. The longitudinal beams ensure continuity between the main transverse beams (MTB) and gives longitudinal rigidity of the platform. Sheave heads are mounted on the end of the main transverse beam to accommodate the lower sheave assemblies. Wood, galvanized steel gratings or steel plates can be used as platform deck. A fully closed steel deck is required if the yard wishes to carry out maintenance activities while the ships are docked on the platform. A closed steel deck in combination with a proper drainage system will protect the environment from polluted waste ﬂuids.
Depending on the selected transfer system the platform will be ﬁtted for rail transport. In case of transfer by rubber tired multi wheel/transporters,
the platform will be ﬁtted with a speciﬁc driving area/lanes. Both lateral and longitudinal transfer of docked ships from shiplift platform to shore (and vice versa) are possible. In case of lateral transfer the platform must be locked at quay level and the transfer system has to pass over the winch systems.
Vertical guiding structures
mounted on the civil pier structure are used to prevent the platform from excessive movements due to strong currents or wind loads. Docking of vessels during strong currents/wind with a non-guided platform can be more difﬁ cult and time consuming. The platform will be ﬁ tted with guiding pads for smooth and accurate guiding against the guiding plates.
The locking devices
are used at land side to enable a smooth transfer from platform to land and vice versa. An electric operated automated locking device will be mounted in the quay wall under the rail transition beams.
The automatic platform locking system
at each winch location (optional) is used for locking the platform at quay level as well as at maintenance level.
The following position levels are deﬁ ned:
- Lower level. System can be submerged to any level within an accuracy of 6mm as long as it remains higher than the lowest level.
- Quay level. Ships can be transferred on and off the platform. At quay level, the platform can be safely locked (optional)
- Maintenance level. Platform is lifted above quay level. This level avoids contact with the seawater (depending on platform height, travel distance and distance from water to quay level) and provides easy access for maintenance purposes. At maintenance level, the platform can be locked (optional system) at each winch, which makes it safer for people working above and/or below the platform
Other important features of the TTS/BR shiplift are:
- Double brake system
- Adjustable winch and platform speed
- Automatic load distribution over winches
- Low starting currents and low power requirements
- Compact winch systems
- Low maintenance costs (enclosed gears, soft starting and stopping etc..)
- Easy maintenance
- Low noise
- Platform maintenance level (underneath of the platform above sea water)
TTS transition rails connect shiplift platform with the pier. Assembly consisting of rails, bearing structure and transition brackets allow easy transfer from shiplift to berth on land and vice versa.
The winch system for the Shiplift system mainly consists of:
- Foundation Beams with upper sheave block assembly and automated locking mechanism at each winch (optional)
- Lower sheave assembly
- Wire rope and load pin assembly The Hoist Winches Assembly generally consists of:
- Winch frame
- Winch drum
- Winch gearbox
- Winch e-motor
- Steel Wire Rope
- Protective Covering
- Electrical components
Depending on which side of the quay the winches will be mounted, a right hand or left hand type winch will be used. The winch system can have a 8-fall, or 6-fall, wire rope system through sheaves. The sketch consists of a upper sheave block with 3 sheaves at quay level and a lower sheave block with 4 sheaves for mounting in the platform, i.e. 8-fall winch system1
Each winch consists of a winch frame supporting a grooved winch drum with an integrated planetary gear box driven by an electric servomotor. Two mechanical fail safe brakes are built-in, one ﬁ tted on the gear box and one ﬁ tted on the servomotor. The servomotor itself also acts as a brake since the motor is able to produce torque at zero speed.
The upper sheaves at yard level, are of the same dimension. One of the sheaves of the sheave-block mounted on the platform has a bigger diameter than the other sheaves to avoid contact of the wire ropes under water (ﬂ eet angle).
The dead end connection of the wire rope is connected to the foundation beam via a load pin. With the load pin, the weight can be determined accurately.2 – 1.2 Winch system
2 – 1.3 Drive & Control System
The shiplift well proven drive & control system is based on TTS/Bosch Rexroth’s wide experience used in many applications handling heavy loads. A conceptual block diagram of the electrical system is provided below. Exact location and number components are shown for example only.
The Drive and Control System contains the following cabinets:
CC: Computer Cabinet
The Computer Cabinet contains the Control computer and accessories. The CC is standard 19” cabinet.
CD: Control Desk
The Control Desk provides the controls and indicators for the shiplift operator. A panel with buttons and indicators is mounted on the CD. It also contains a ﬂ at panel display.
MCC: Motor Control Cabinet
The Motor Control Cabinets control the AC servomotors mounted on the winches. Due to signal quality requirements, a MCC – winch motor distance limit applies.
LDB: Local Distribution Box
Each winch arrangement is equipped with a Local Distribution Box. It connects the sensors on the winch arrangement and controls the locking devices.
The MCCs shall be mounted inside an acclimatized MCC room. The Computer Cabinet and Control Desk shall be mounted inside an acclimatized Control
Room. MCC’s and Control Room can be delivered as “plug and play” customized acclimatized containers. Power and control cables interconnect the cabinets and the winches. The length of every individual control cable shall not exceed 140 meter.
The Control Computer is based on Linux, real time system, which executes the TTS/Bosch Rexroth Shiplift Control Software. The Control Computer connects the Control Desk with the Motor Control Cabinet and the Local Distribution Boxes on each winch arrangement.
To support troubleshooting, the Control Computer can be connected to a Virtual Private Network (VPN) router; router is not included in the scope. This router connects to the TTS/Bosch Rexroth network via internet. Through the VPN, Bosch Rexroth is able to perform remote monitoring and diagnostics. Remote access by TTS/Bosch Rexroth is only possible after customer consent and requires Internet Access. Internet Access to the Computer Cabinet is not in the scope of supply.
The Control Desk, the Motor Control Cabinets and the winch arrangements are equipped with Emergency Stop push-button. When any of the Emergency Stop push buttons is being pressed, all winch motors are stopped in an safe controlled way while the brakes are being applied, If however the winch motors do not stop in time, as a double safety, the power supply to the motors will be switched off so the brakes will be applied as well.
The Control Software is responsible for a safe and controlled operation, start-up and shutdown of motor controllers, position / listing / altitude control of the platform and monitor/control of various error conditions.
Features of the Control System:
- Up / down / stop
- List / trim
- Locking of the platform
- Load balancing
- Manual operation of a single winch or winch pair
- Manual operation of a single locking device
- Logging of shiplift operations
- Service support: reeving/unreeving of wire rope, position calibration, winch data presentation
- Normal, advanced, service operator levels
- Graphical user interface
- Printer support
The Logging feature logs all operational events and conditions that are encountered during any shiplift operation. The current log is displayed on
screen and stored on the harddisk of the Control Computer. Log ﬁ les are not deleted by the Control Software.
The system is provided with a user interface that is operator friendly and easy to use.The main window provides coloured bar graphs that visualizes the load of the platform.The left side of the window shows status indications of the system. The lower region of the window provides position and load data. The position of the centre of gravity is indicated on the platform. At the top of the window, a menu system provides access to additional supporting windows
2 – 1.4 Inhaul & Positioning System (Optional)
There are different ways of inhauling and positioning vessels into the shiplift pit prior to docking.Small ships can be handled manually or with use of capstans.
Larger ships will require inhaul winches for inhauling and capstans for positioning. Maximum capacity of the winches and capstans depends not only on the ships displacement but also on the maximum wind loads and water currents allowed during the operation. For bringing a ship safely inside the lift pit a tug boat will normally be used, before the inhaul and positioning system will “take over” the ship.The inhaul and positioning system can be simple and manually operated, but can also be made fully automated with auto-tensioning winches and an
inhaul & positioning control system.
Another option is to make use of 4 capstans/inhaul winches and two or four trolleys which run on two longitudinal guide beams mounted at each side of the shiplift pit. The trolleys will be connected to the ship from each side in order to keep ship in the centre of the pit. With one of the two capstans at front of the lift the ship can be pulled inside the lift pit while the ship is kept in the centre by two or four trolleys. Once the ship has been hauled in the four capstans can be used to position the ship more accurate.
This type of inhaul system makes the inhaul operation more efﬁ cient and safer. In case side wind loads occurs the vessel will be held by the trolleys on the rail beam.
The Ship Transfer System (see General Layout)
mainly consists of:
- Transfer Trolleys
- Power Control Car (PCC)
- Connection Stays between the transfer trolleys
- Trestles/ optional keel beams
The Ship Transfer System (STS) is a modular system built up of a set of free standing trestles with twice the number of Transfer Trolleys running on rails. The trolleys are hydraulically powered by the power supply unit (PCC).
The Power Control Car (PCC) feeds power and controls the transfer trolleys. From the hydraulic power pack – on PCC – the hydraulic power is distributed to the Transfer Trolleys through lines of hydraulic hoses. Depending on system size and capacity one or more PCC’s are included.
The hydraulic circuit is designed in such a way that the ship can be supported in a “Floating” mode or in a “Spring” mode. Based on the size, weight and position of COG (Centre of Gravity) of each type of vessel, the main lifting cylinders are connected into three or four groups or zones. The three groups are selected to achieve a virtually three-point support to the vessel, while allowing an equalized distribution of loads within each zone.
The hydraulic ﬂ ow is proportional controlled by the 2 – 2 SHIP TRANSFER SYSTEM (STS)
During the transfer of the vessel, the operator can at any time stop and “freeze” the system. The load will in “freeze” mode be under control of the relief valveon each transfer trolley.
The rails can be orientated parallel and/ or 90° to theshiplift platform enabling the transfer system to moveships both in lateral and transverse directions onto and off land berths. The transfer system will move the vessel on a ﬂ uid bed with full control over the forces to the hull and the wheel loads.
The transfer system can be used as one big system or split into smaller transfer systems for transfer of smaller loads.
2 – 2.1 Transfer trolleys
Each Transfer Trolley is equipped with a hydraulic main lifting cylinder to lift and carry the load. The Transfer Trolleys are all equipped with a hydraulic drive unit.
All the hydraulic items will have their hydraulic power supply through hydraulic hoses that are connected to the transfer trolley by means of hydraulic quick connectors. There are only hydraulic ﬂ ow control valves and relief valves on the transfer trolleys, no electric operated valves. This means that the Transfer Trolleys can be submerged for launching and retrieval of the vessel.
During transfer operations the cylinders are working as an average at mid of the remaining stroke. This means that the STS will have the capability of accommodating unevenness of the rail pattern or settlements of the ground under load in the typical range of +/- 100-200 mm depending on the actual stroke selected.
To change the transfer direction from longitudinal to transverse movement on a single level system, the trestles are lowered to the ground. The trestles are either equipped with claws up under trestle wing, or additional lifting cylinder with rotation plate at each trolley. The main cylinder/ or additional lifting cylinder can lift the transfer trolley free off the rails, allowing one man to manually rotate the transfer trolley to a new direction, before lowering the transfer trolley on to the perpendicular rails.