From compact shock absorbers to advanced passive heave compensation systems
Cranemaster® shock absorbers and passive heave compensators are robust, reliable and easy to use. The units are designed to reduce impacts in offshore lifts above sea level, through the splash zone and subsea. For more than 30 years they have proven to be both effective and dependable.
For demanding operations we offer several solutions for enhanced performance and control. All control systems are designed with maximum focus on safety, and depending on system, they offer sensor redundancy, manual override and fail-safe modes. The computer based systems are DNV GL technology certified.
Passive Heave Compensators (PHC)
Mounted between the hook and the load, Cranemaster® Passive Heave Compensators (PHC) expands your vessel capabilities and protects your crane, lifted object and personnel. The result is improved operational weather window, reduced probability of snap loads and reduced heave motion.
- Spring-damper system based on gas pressure and hydraulic fluid.
- Self contained – no external connections of hoses or wires required.
Load range: 0,5 – 1400 ton / Stroke range: 0,5 – 5,0 meter
Failure free operation thanks to robust technology.
Developed and produced in Norway.
May be equipped with High Performance Features (e.g. Quick Lift and Lock & Release).
Connected in series for increased stroke.
Connected in parallel for increased load.
Cranemaster® Adaptive Control — Adaptive change of settings during lifting
Subsea lifting operations typically have several phases, including lift-off, splash zone crossing, lowering and subsea landing. For optimal performance, each phase requires a different setup of the PHC unit. The Cranemaster® Adaptive Control (CMAC) system will give you optimized performance through automatic change of settings for the various phases. The adaptive functionality was used for the first time in the Gorgon project in 2013.
Quick Lift – Avoid re-contact after lift off
For cranes with a slow lifting speed, there may be a risk of re-contact between the structure and the barge. Using on-board Nitrogen pressure, the Quick Lift functionality will lift the load by pulling in the piston and thereby avoiding re-contact.
Lock & Release
The radio-controlled locking system will reduce rigging height by locking the piston in zero-stroke during over-boarding, avoiding the static stroke in air. The system may also be used to lock the piston subsea if required based on depth or ROV control.
Weight & Temperature Correction
Correction in air and water for temperature variations and variations in load weight and buoyancy. Deviations from calculated loads weigh does not influence performance.
Compensates for temperature variations and changes in buoyancy.
Advanced Splash Zone Tension mode (CAST)
The Cranemaster® Advanced Splash Zone Tension mode (CAST) changes the spring characteristics continuously during the stroke cycle, providing an optimized stiffness at each stroke position. This will give an enlarged operational weather window and the probability of slack slings and/or high DAF will be significantly reduced even for the most challenging objects.
CAST is particularly useful for objects with large horizontal surfaces (e.g. manifolds, templates and suction anchors) and objects with high buoyancy compared to weight (e.g. protection covers and mud mats).
Monitoring & Logging
Monitoring | ROV monitoring and control (e.g. piston lock subsea). System setup via radio or WiFi. Logging of forces, velocities, accelerations, pressures, stroke and temperatures for post-lift download and analysis.
Logging | Logging of all system data, sensor input, forces and movements during operation. Can be used to verify system performance, actual landing speed, splash zone forces etc.
Cranemaster® Passive Depth Compensation
A common challenge when using Passive Heave Compensators in deep water, is the deep water pressure pushing the piston back in, resulting in reduced efficiency of the system. This can be solved by utilizing Cranemaster® Passive Depth Compensation (CMDC). This is a patented1), robust solution especially made for deep water operations. Stroke remains constant independent of depth and potential resonance during lowering is eliminated. The solution excels in its simplicity, there is no need for a control system.
1)InterMoore Inc., the owner of US patent 7934561 “Depth Compensated Subsea Passive Heave Compensator”, has granted Cranemaster an exclusive worldwide right for the use of this patent.
Active Heave Compensation
Rental Fleet — Ready for immediate mobilization