One of the challenges exploring for oil and gas in deep and ultra-deep water is load handling. Cargo-handling equipment manufacturer MacGregor has focused on overcoming the limitations water depth places on conventional steel-wire offshore cranes to improve safety and efficiency. As well as the load, these cranes must bear the ever-increasing weight of the steel wire as it is paid out, limiting a crane’s permissible load in relation to depth.
“By using fibre-rope, which is neutrally buoyant in water, a crane is able to use its full lifting capacity on the load, rather than the steel wire, at practically any depth,” said MacGregor sales and marketing manager, load handling solutions Lene Stray.
“The benefits are enormous,” said Ms Stray. “Water depth is no longer an issue, but far more significantly for flexibility and cost-efficiency, a smaller crane and vessel can be used for more and larger assignments, enabling its owner to bid and operate on a wider range of contracts.”
Ms Stray said fibre-rope is substantially lighter, easier to store and significantly less expensive to transport compared to steel wire. She also said visual inspection of a fibre rope is much easier, requiring no industrial radiography or ultrasonic testing. “If sections need to be repaired or replaced, new lengths can be spliced in with ease,” she added.
The condition of steel ropes, she said, is much harder to monitor. “Five-yearly class rules require owners to cut off sections and send these away for testing, while annual inspections could see the entire length having to be replaced if there are any signs indicating damage.” She also noted that steel ropes require greasing to protect them from corrosion and ensure smooth handling, while fibre-ropes do not.
MacGregor has a monitoring and management system that uses 3D technology to continuously measure all key parameters, scanning the rope’s surface to check for abrasions and anomalies, track temperature and cool it automatically with water as necessary.
Fibre-rope technology is not new, but its application to offshore cranes is. “There are several reasons for this,” explained Ms Stray. “We know that the offshore industry has struggled for the past few years, and the introduction of any new technology, no matter how significant, requires investment and confidence.”
A cornerstone in the crane’s development was regulatory compliance. FibreTrac is fully-certified in compliance with DNVGL-ST-E407 regulations. A full-scale version of MacGregor’s first FibreTrac crane was delivered this year for testing and it is now a commercially ready product.
Connected crane gets smarter
New offshore cranes are delivered with advanced connectivity built-in and the majority of cranes in service already have this inherent capability. This is in preparation for another technological step forward; the ability to add intelligence to the maintenance platform.
“High-quality, accurate, predictive maintenance is possibly one of the most important elements of service provision,” said MacGregor director service business models, digital and new business transformation Daniel Lundberg. “We have pilot programmes trialling these capabilities with a select group of offshore and merchant customers and plan to introduce a working prototype of our predictive service tool, MacGregor OnWatch Scout, during 2019.”
OnWatch Scout detects variations in the behaviour of components, allowing MacGregor to notify customers and advise them of the preventative steps that need to be taken to avoid component failure.
Minimising downtime improves revenues
“Predictive tools,” said Mr Lundberg, “which enable one to understand tomorrow’s events today and help to reduce downtime, ultimately reduce maintenance costs and increase revenue and profitability.”
OnWatch Scout builds on years of operational data derived from MacGregor’s current service tool, OnWatch, which provides operators with a rapid remote support capability once an equipment issue has been detected.
Using events recorded through OnWatch, MacGregor has used lessons learnt to apply intelligent machine-learning and algorithms, explained Mr Lundberg. MacGregor is validating this data to ensure it is applied correctly to actual service events logged with its equipment and is engaging with its service engineers to fully understand these and the steps taken to rectify them.