In-depth | HEAVY LIFT Safe and steady


A new motion compensation platform has been designed to grant standard barges the ability to safely accommodate cranes with SWLs akin to those aboard jack-up barges, at half of the cost


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ffecting crane operations in rough sea conditions is typically an expensive task, usually


necessitating the deployment of a jack-up barge to ensure both operational efficiency and crew safety. However, a Netherlands- based company, Barge Master, is attempting to lower operational costs and increase safety with the launch of a self-titled motion compensation platform, designed to be affixed to any barge, and with the capacity to handle up to 700 metric tonnes. Installing a standard crane directly onto


a standard barge can endanger personnel should the load begin to swing violently in harsh gales and tides, particularly when operating in high sea states. It is, therefore, far from being a common procedure; as Martijn Koppert, chairman of Barge Master, tells Offshore Marine Technology: “We don’t really see crane barges in the North Sea – they are more likely to be found in the Gulf of Mexico, South East Asia and the Middle East, but they also coincide with a high frequency of accidents.” To combat this problem, the


Barge Master functions as a motion- compensating conduit between the barge and crane. The platform is supplied as a containerised package, as a hire or purchase option, which crew members can manually assemble on board. Koppert says: “Typically, Barge Master is housed in 10-12 separate containers, which can be liſted onto the barge via crane while the vessel is at the quay wall. It takes about a week to complete the onboard assembly. “Ten, when the job is completed, or


if the vessel has a different mission to undertake, it is easy to re-pack the platform into the containers and move them back to the port or harbour as needs be.” The Barge Master is supported by a


control room and a hydraulic power unit, both housed in 40ſt containers stacked


on top of one another. Rather than draining energy from the vessel, the Barge Master can be powered by three 20ſt container-housed diesel generators, producing 1,500kW.


Motion compensation Te Barge Master concept functions on the principles of six degrees of freedom (DoFs) to remain still during sea operations. This approach takes into account the fact that, in a 3D environment, six DoFs need to be compensated to prevent the platform from moving. Of these, three DoFs are compensated by restraining two translations, namely ‘surge’ and ‘sway’, and one rotation, ‘yaw’, via the barge’s anchors or dynamic positioning (DP) system. Te remaining three DoFs, comprising the translation ‘heave’ and the rotations ‘roll’ and ‘pitch’ are compensated by the Barge Master itself, via the system’s set of three hydraulic actuators. These actuators produce the counteractive motion necessary, in conjunction with the above factors, to keep the platform relatively still compared to its surrounding environment. Te platform was developed by Barge


Master in tandem with Bosch Rexroth, initially focusing on cranes with payload capacities of up to 400tonnes. Prior to its


Offshore Marine Technology 1st Quarter 2013


In sea trials, the Barge Master was proven to function safely in significant wave heights of 1.5m


launch in December 2012, the system underwent a series of sea trials, in a format comprising a Barge Master designed to accommodate a 700tonne payload, and a 250tonne LR1250 crane. In these tests, the system was proven to function adequately in wave heights of up to 3m and significant wave heights of up to 1.5m, Koppert says. Te system can be customised to suit


a range of customer needs, from smaller- scale models with lesser payloads up to platforms capable of safely dealing with 2,000tonnes. As a company, Barge Master is able to work with customers and create technical proposals. “We normally can ensure a wave-induced motion compensation of 95%,” says Koppert. In addition to undertaking oil and


gas-related tasks and quay / port structure construction, the platform would also be suited to offshore wind farm installation projects, Koppert adds. In terms of cost, the Barge Master retails at between €5-10 million (US$6.8-13.5 million) when purchased, which Koppert estimates to be approximately 50% less expensive than the costs associated with deploying a jack-up barge to handle operations. Similarly, users can avoid other time-consuming considerations that need to be made when utilising jack-up craſt, such as testing for adequate soil conditions, he says. OMT


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