A number of new technology products and services and contracting procedures are emerging for installation and removal of offshore facilities. These products, services, and procedures are providing alternatives to the traditional methods of doing work offshore.
Emerging technologies are being used to reduce installation time, reduce material cost, or to reduce the installation risk. These technology trends are: Resin Chamfering Wheel
In 1987, the use of pile swaging (Hydro-Lok) in lieu of grouting to secure subsea templates to the ocean floor was introduced into the GOM, after a record of successes in the North Sea. The success encouraged a joint industry study which evaluating Hydro-Lok's ability to secure piles to the jacket taking into account cyclic loading.
As a result of the joint industry study, the swaged connection was first used on two platforms in the GOM in 1990 and the Auger TLP in 1992. Oil States has continued to refine the Hydra-Lok connection and has established the swaged connection as an alternative to grouting. Hyda-Lok has been selected for four major jacket installations in 1998.
An emerging technology which has reduced platform abandonment costs for Offshore Specialty Fabricators (OSFI) is the use of abrasive water-jet pile cutting systems as an alternative to explosives. Explosive cutting of piles requires an expensive turtle watch prior to and after the explosion, thus limiting the cutting of piles to daylight hours. OSFI has been very successful at using the abrasive water-jet cutting approach. They now use this approach on about 80% of their abandonments.
Jim Jones, Operations Manager for OSFI and a strong advocate of abrasive cutting, says that "in the past there has been negative experiences" with abrasive water-jet pile cutting that has caused many of the contractors to still prefer explosives. "Abrasive water-jet cutting doesn't do a good job on conductors" he pointed out.
"There are eight to ten companies trying to get into the abrasive water-jet business and they come and go" according to Jones. OSFI's success can be greatly attributed to their use of Oil States MCS's abrasive water-jet cutting system. Charlie Fahrmeier, President of Oil States MCS says that "the reliability of abrasive jet cutting has improved dramatically over the years." OSFI and Oil States MCS have worked together to develop a launch frame for handling the cutting manipulator for the abrasive water jet pile cutting system while inside the jacket column and pile. The launch frame frees the derrick barge cranes for other activities.
According to Cal Dive, 10% of their jacket abandonments are now done by using the abrasive water-jet approach. On Cross Offshore Corporation's abandonments, 100% of their piles and conductors are severed using their own proprietary abrasive water-jet system. Tommy Jahncke of Cross Offshore states that they "haven't used explosives in three years." On about 10% of Diamond Services' jacket abandonments, abrasive water jet cutting methods are used. Jim Furlette of Diamond Services firmly believes that "explosive cutting is much more reliable, but operators prefer to avoid using explosives because of the environmental concerns for turtles and dolphins."
OSFI has also been promoting the concept of fast-track project by buying and refurbishing decks, jackets, and production equipment on speculation. Their concept is to reduce the critical path time for an operator to start producing as soon as possible by reducing the time to deliver production facilities. Their off-the-shelf approach for new and refurbished facilities is offering a solution to a market where delivery times for facilities are increasing.
Jimmy Nichols of Cal Dive International reports they are using a "project management approach" to abandoning wells, platforms, and pipelines. They manage their own in-house services and contract other contractors to assist with the abandonment process. They have one well plug and abandonment (P&A) crew which abandons the wells. They also have crews and equipment that can prepare the platform for abandonment by another contractor. Cal Dive has a good relationship with McDermott. McDermott performs abandonment work as a subcontractor on platforms beyond the lift capability of the Cal Dive I barge. Their in-house diving vessels are used to abandon pipelines, perform bottom survey and conduct platform site remediation.
Another lift contractor which uses the project management approach is Global Industries. Halliburton Energy Services and Global Industries have an alliance called Total Abandonment Services (TAS), which coordinates the complete abandonment process. Halliburton provides the P&A expertise, while Global Industries provides the diving and lifting capability.
A third contractor using the project management approach for abandonments is Cross Offshore Corporation. The company has eight well P&A crews and abrasive cutting units, and a liftboat as project support vessel for abandonments to 100 ft water depth.
They offer an integrated single source for facility abandonments and removals.
Another trend that is emerging in the GOM is the increasing length of the operating season because of vessel capabilities and contracting approaches. Traditionally in the GOM, the contractor would only incorporate weather downtime in their lump sum bids from May 15 to October 15 except for named storms. However, Heeremac bids the Balder, a North Sea class semisubmersible crane vessel, as taking weather all year in the GOM except for named storms. Another exception is Offshore Specialty Fabricators. They are willing to assume weather on turnkey projects, except for named storms.
Installation contractors have been telling operators that they can reduce installation costs by getting involved with the project earlier. They can then understand the client's needs and apply creativity and experience to reduce the installation time. Stephen Davey, Resident Manager for Saipem in Houston points out that "contractors want to focus on the job, and not on the competition." The traditional method of bidding the installation contractor at the end of the engineering process forces the contractor to focus on winning the bid and not the project. Davy feels that contractor should "get out of the box, talk, listen, and ask the operator: why are we doing things this way?"
According to Bill Higgs, Vice President at Mustang Engineering, "one of the keys on fast-track projects is to do things only once if possible. When the engineer has to design for installation by any of three vessels, design for integrated or split deck options in order to preserve a bid scenario, the design is not optimized. Taking the time to optimize after bid would slow down fabrication. So, there are a lot of savings in time and cost by selecting the contractor early."
In 1997, Searex revived and updated the concept of using a jackup to perform offshore construction work. The owners of Searex have designed some unique features in their self-propelled jackup based on their experience of operating liftboats. They have demonstrated that Cajun ingenuity is still alive and well. Their patented crane rotates around the bow starboard leg, thus allowing a 210-ton capacity crane to rotate 360 degrees, free-up valuable deck space, and better transfer loads into the hull and leg. Using an "aircraft carrier" approach, they moved the deck house to the port side and freed-up valuable deck space for working area. Searex plans to build four jackups at Alabama Shipyard. The first jackup is scheduled to be available sometime in the 2nd quarter of 1998, and the second during the 3rd quarter of 1998.
Elevating Boats (EBI) is considering getting into the lift contractor arena with a super class liftboat called the Mammoth Elevator. The Mammoth Elevator has two 250-st ABS/API rated cranes. It is due out of the shipyard in late first quarter of 1998. EBI has historically limited their liftboats to liftboat service type work, but is considering being an installation or abandonment contractor. Cross Offshore Corporation is considering the addition of a heavy class liftboat for its fleet through charter or newbuild.
Global has a fleet of 22 liftboats with crane capacities of 15-100 tons used to support platform installation and abandonment activities. They were not included in the study since Global's liftboats are not the primary lift vessel, but support the installation or abandonment work. Global is not actively marketing them as installation vessels.
Kelly Steele of Bisso Marine says that they have a policy to inspect the structure prior to turning in the bid if the weights come close to their crane load-radius limitation. Steele noted that "actual lift weights can be 20% to 30% higher than what was provided" in the bid information package.
For reference, the world record for a single barge lift is 12,502 short tons, which is held by Heeremac. This record was established when the production utility deck for Piper Bravo was installed by the DB102 during the winter of 1991 in the British Sector of the North Sea. And the world record for a single lift in the DP mode is held by Saipem's S-7000, a 11,650 st lift of BP's Andrew field integrated deck.
Among the major installations in 1996 were:
The first GOM contractor to set up a web site is Global Industries. Their web site athttp://www.globalind.com is a collection of screens that provides information about Global Industries. Information about each lift vessel is provided. This site will be a trend for the industry.
At press time, Offshore Specialty Fabricators and Cross Offshore Corporation were developing web sites that will allow customers to read about their used platform jackets, deck sections, and offshore production equipment that are available for purchase.
Later in 1997, J. Ray. McDermott is supposed to have their North America web site on line. Searex is also developing a web site which will be available in late 1997.
Requests for quotations, budgetary cost estimates, and technical information will become easier access as each contractor establishes E-mail capability via the internet.
If the pull-out section on Gulf of Mexico heavy-lift vessels (PART I on pages 49-64) is missing from this issue, readers may obtain another copy by contacting:Diana Green, Offshore Magazine, 3050 Post Oak Blvd., Suite 200, Houston, TX 77056; Fax: US (713) 962-6296.
Dry Diamond Squaring Wheel Copyright 1997 Oil & Gas Journal. All Rights Reserved.