Anti-heeling system for NPCC Al Maryah
NPCC had a requirement for a highly efficient and market-proven anti-heeling system to ensure safety of navigation and vessel stability for its diving support vessel NPCC Al Maryah during its chartered operations.
Vessel stability is a highly complex field of science, and its relationship to safety of navigation is dynamic in relation to variable forces resulting from beam winds, waves, turning, heavy-lifting, cargo loading/unloading and other causes. Elcome’s technical team evaluated the ship’s requirements and proposed a Hoppe Anti-Heeling System to NPCC.
Fully automatic anti-heeling operation
The anti-heeling system works by automatically measuring the vessel’s heeling angle and transferring water from one side (port or starboard) to the other to compensate. The water transfer is automatically triggered when the angle of heel exceeds a set value, and the operation continues until the righting moment equals the heeling moment.
The anti-heeling system was designed with two reversible vertical propeller pumps of 31 kW each with a flow rate up to 500 m³/hour. Hoppe Marine’s HOPAC pneumatic rotary type actuators are double-acting and single-acting, with butterfly valves for open/close functions. The actuators can be operated with 7-12 bar standard working compressed air available on the vessel and are driven by Hoppe’s PLC based HOMIP valve remote control system. It acts as the signal hub between all process components and control workstations or other centralised ship management systems via Ethernet TCP/IP, serial RS485 and RS422 interfaces.
In the automatic mode, the system continuously measures the inclination and begins to compensate the heeling angle when the threshold value exceeds ±1.5° heel. The inclination values range from 5° port to 5° starboard.
The 6-inch touchscreen of the HOMIP integrated control unit provides clear, user-friendly and structured visualisation of the fluid systems, including piping, valves, pumps, switches, treatment units and tank contents.
Made for long and continuous anti-heeling operation
The Hoppe Anti-Heeling System is designed and built for reliable performance with very little maintenance under the extreme environmental and operational conditions of a vessel.
Reversible propeller pumps for anti-heeling operation
Two pumps of axial reversible propellers, designed for controlled bidirectional water shift, are used for the operations.
In automatic mode, the system continually measures heeling angle and compensates with a flow rate up to 500 m³/h.
Hoppe Marine integrated touch screen control unit
The PLC unit with 6-inch integrated touchscreen offers screen layouts for automatic or manual control and can be connected to the ship management system via Ethernet TCP/IP, serial RS485 and RS422 interfaces.