TRIM LIST SKEW ANTISNAG
Hydraulic TLS actuation is the most versatile system of spreader positioning system besides guaranteeing a perfect control of the position. It can be customised to perfectly fulfil the needs and the habitudes of operator as well as maintenance and different operational exigencies through its peculiar features:
• Possibility to adjust and memorize different speeds for each movement, utilising proportional flow control.
• Exact knowledge of the position of each actuator on real time, utilising the position transducers.
• Possibility to recover, easily and without manual intervention, unequal lengthening of ropes.
• Possibility to be installed either directly on the lifting ropes or on reeving sheaves through levers.
• Possibility to integrate an ANTI SNAG system.
They are driven by operator. The stroke indicators assembled inside the cylinders act as reference fo stop position of cylinders.
The movement speed canbe fixed or variable according to required solution.
It is possible to memorise and to find againautomatically some positions of stability by stroke indicators.
High speeds and general performances of last generations quayside container gantry cranes require motors with high power. While rising up an empty spreader at max speed the kinetic energy accumulated in the driving system is enormous. In case of the spreader’s engagement into the ship cells the kinetic energy becomes a potential high risk for mechanical and structural components of the crane.
In this eventuality our Anti-snag system is vital to prevent ropes and crane parts from damagement.
An efficient Anti-snag system can save cranes while operating on the ship.
Our Anti snag is perfectly integrated in our TLS system. Anti-snag is based on:
• Laboratory tests are essential to check and optimize the design and realisation of the components. Simulating the snag event we define exactly the type of solicitations occurring during the snag phase.
• Anti-snag valves made by Rima.
• TUV certification (German register) of the reaction time of the hydraulic system through oscilloscope tests.
• Studies about the interface/interaction with brakes/drives systems.
• Long experiences in application on many different types of cranes within many countries of destination. Even in case of giant power container cranes (lifting speeds up to 180 m/min).
If the spreader bumps into hold of ship or into otherobstacle, the pressure into cylinder increases. When pressure value exceeds a settled value (usually 25% more than max working value) the Anti-snag valve opens itself very quickly (opening time as not to be major than 50 mms) allowing oil to flow in pressureand bump energy to be absorbed. At the same time suitable load cells stop the lifting motor.