The process of operating a crane for offshore applications is not without its challenges. While safety is of paramount importance, firms in the sector are also required to supply and use equipment which can not only withstand the tumultuous environments, but also support the demands of a construction project.

Safety for those working at offshore sites in unpredictable conditions is behind many of the decisions made concerning equipment and processes.

The International Marine Contractors Association (IMCA) – a trade association which represents offshore, marine and underwater engineering companies – helps to promote health, safety and environmental standards for those working in the industry. The association’s attention to these standards is indicative of the need for companies working in the industry to follow suit.

The IMCA states the importance of personnel competence in the offshore oil and gas industry. The association’s technical director, Jane Bulger, says: “Encouraging organisations to implement competence schemes is one of the mainstays of the IMCA work programme. There are frameworks in place for each of its technical divisions – marine, diving, remote systems and ROV, and offshore survey. Development and implementation of a scheme is then up to individual organisations.

“During 2010, as part of our ongoing campaign to encourage implementation, we held a well attended competence workshop aimed at contractors, their competence and training representatives, and offshore personnel. Competence is a combination of training and experience. To have an effective competence programme in place, there needs to be ongoing employer/employee interaction and assessment over long periods (years) and a wide variety of responsibilities within a role which delivers huge value to both parties. We can, and must, encourage the take up of competence schemes all over the world.”

Over 700 companies are members of the IMCA, which was established in 1995. The association produces good practice documents, as well as training and workshop sessions to help reduce the number of accidents in the industry.

Safety first
A focus on safety is adopted across the industry with firms aiming to address workability of equipment in adverse conditions.

Aberdeen- based firm, Sparrows – one of the world’s largest offshore crane engineering contractors – has enjoyed a continuing relationship with BP since 1975. The firm supplies all crane and lifting engineering services on BP’s 26 UK offshore installations and four onshore sites.

Safety is Sparrows’ main concern. Alex Mowat, Sparrows contract manager for the BP assets, explains the process the firm has in place to ensure the safety and risk minimisation without reducing productivity at the BP partnered job sites. He says: “Under the contract, Sparrows operates, plans and implements preventative maintenance programmes covering 42 pedestal cranes by manufacturers including Liebherr, Stothert and Pitt, Kenz, Favco, Stalprodukter and Hydralift.

“As with most of our clients, the preventative maintenance programmes for BP are derived from FMECA (Failure Mode, Effect and Criticality Analysis) studies conducted by Sparrows which examine every component and system of the crane, identify every potential failure, and attach a potential frequency and severity of consequence of each potential failure. Probability x Potential Severity of Outcome = Risk, and maintenance efforts are then targeted in proportion to this assessed risk.

“This risk-based maintenance assures the client of maximum safety and technical integrity – but simultaneously delivers best value in maintenance planning and delivery.”

Mowat explains the firm’s approach to safety in layman’s terms. He says: “Safety is critical but is directly linked to engineering integrity: the quality way is the safe way.”

Working offshore may present a number of challenges to firms but the rewards can be sweet. Sparrows recently received the Queen’s Award for Enterprise for more than trebling its annual exports to £78m between 2003 and 2009.

The firm operates across six continents, with office locations including Abu Dhabi, Singapore and Houston, and is currently involved in a lot of mid-life upgrade projects, i.e. upgrading or replacing cranes which have been operating for twenty years or more.

Sparrows, however, remains Scottish based – the UK base holds 60% of its global workforce – and cites the UK North Sea as still being a major hub of the offshore energy sector. However, when discussing locations further afield, Doug Sedge, CEO says: “There are exciting opportunities, especially as the industry moves into deeper water. This is particularly true in regions like West Africa, Brazil and the Gulf of Mexico – and Sparrows is active in all of these.”

Barge motions
The dangers and practicalities of working offshore can present firms with a number of challenges, including how to maintain stability throughout the job. To tackle this, Martijn Koppert has created the Barge Master.

The Barge Master is the result of extensive research and cooperation with Bosch Rexroth and TWD. It works by using a standard crane and a standard barge, with a motion compensated platform in between.

The Barge Master aims to increase safety and workability. Through his background in marine and civil engineering, Koppert has experienced the problem of downtime due to swell many times and therefore wanted to provide a solution for those working in the sector.

“We are currently in the testing stages. Our scale model will be ready by January 2011, with construction set to be carried out throughout the coming year. We have ordered the first Barge Master, which will be delivered by late 2011, early 2012.”

But how does the Barge Master work? One of the challenges experienced by those on deepwater Floating Production Storage and Offloading installations (FPSOs) in the offshore market is the effect of the swell, or long waves, on the vessel; the dynamics of these ‘ship-to-ship’ lifting operations impose their own demands on both crane and crane operator.

This is a problem Sedge from Sparrows can appreciate: “We cut our teeth as a company working in the North Sea, one of the toughest operating environments in the offshore world: that puts our expertise in demand when clients begin operating in other harsh environments.”

The relatively small rotations of the barge, perhaps 2-3 degrees, on which a crane is placed cause large movements of up to four or five metres of the crane boom tip, and subsequently the load. As a result, the safety of those working to erect these installations is reduced and operations are often suspended.

This downtime is something Koppert states the Barge Master can combat.

Six degrees of freedom (DoF) must be compensated in order to prevent movement of the crane/ supply platform. Three DoF’s are compensated by restraining two translations (Surge and Saw), and one rotation (Yaw) of the barge through anchors or dynamic positioning systems. The remaining three DoF’s (one translation – heave – and two rotations – roll and pitch) are compensated by the Barge Master, which is driven by 3 hydraulic actuators.

By measuring the heave, roll and pitch, and controlling the actuators supporting the platform to produce the counteractive motion, the platform stands still, relative to the fixed world.

No stranger to offshore lifting operations, entrepreneur Frans van Seumeren, also sees the advantages and potential of the Barge Master system. The former CEO and owner of Mammoet has recently become a 50% shareholder of the company and he chairs the supervisory board. Van Seumeren said of the Barge Master: “It allows for two crucial aspects of offshore work: increased safety and a large weather window for lifting operations.”

The firm will be showcasing the system at a number of exhibitions in 2011, including the AOG in Perth, the OTC in Houston, Offshore in Amsterdam, and the Deeper Offshore Wind Convention in London, where the firm will present its scale model.

Building giants
Huisman Equipment, based in Schiedam, was originally founded in 1929 as a steel construction firm and later focused on the shipping industry. Today Huisman is a company with extensive experience in the design and manufacturing of heavy construction equipment for world leading offshore firms. The company has four main branches – cranes, winch systems, pipe-lay and drilling equipment.

Gerben Roks, sales manager at Huisman, explains how the firm copes with the risks of working with heavy equipment in a marine environment: “Our equipment is often one of the critical components aboard; if the main crane on a heavy lift vessel malfunctions serious safety issues can occur. Therefore we pay high attention to safety during the design stages of our products. Safety is an essential design parameter and it is translated in ways to increase the reliability and to overcome manual assistance.

“For all of our equipment the redundancy level is very high. The equipment is fed from the vessel with two independent power supplies; the control system is outfitted with battery units and hydraulic systems are fitted with accumulators to prevent unsafe situations during power failures. Mechanical components also have back-up systems to overcome single point failures.”

Roks continues: “On our drilling equipment, automation is one of the drivers to increase the safety level. Working on a drill floor is one of the most hazardous environments you can imagine. Our goal is to build a fully automated drill rig where limited manual assistance on the drill floor is required.”

Huisman now has three facilities, in China, Holland and the Czech Republic. This ensures the firm can provide local support for its customers and the shipyards. Roks indicates that the more technologically complex projects, such as pipe-lay systems, still remain in Europe in order to exert better control, and to ensure these projects are delivered to the safety standards of Huisman.

Connecting the pieces
Cargotec’s marine division offers MacGregor solutions, used in the maritime transportation and offshore industries. The firm strives for safe, efficient and reliable operation of cranes, hatch covers, RoRo and cargo lashing equipment, as well as bulk handling and offshore load handling systems. Cargotec also supplies MacGregor cargo access equipment for naval logistics vessels, as well as linkspans and Siwertell bulk handling equipment for ports and terminals.

The firm acquired Hydramarine in Norway and Plimsoll in Singapore in 2007-these became the foundation for Cargotec’s offshore load handling. These acquisitions have enabled the firm to provide integrated MacGregor marine and subsea handling systems, operating in three offshore segments, subsea load handling, anchor handling and towing and mooring operations. The firm also offers energy-efficient bulk handling systems for offshore supply vessels.

While safety is imperative for project planning on offshore applications, Sedge highlights the vital role of cranes in the offshore supply chain. He says: “Cranes are the ‘arms’ which feed the rigs. While it may not be apparent, cranes are a crucial part of these processes.”