CALM buoys have long been utilized to safely and reliably transfer liquid petroleum products between a vessel and a shore facility without the need for a jetty extension into deeper water. These buoys have been used around the world as marine terminals in water depths ranging from shallow to ultra-deep water. Gulf Copper & Manufacturing Corporation recently completed a unique project to build five (5) massive CALM buoys for SOFEC Inc. which are now being used to offload liquid product such as diesel or gasoline in Latin American locations lacking deepwater ports. The project is of particular interest from Gulf Copper’s view as they represent a new line of business for the company.
The buoys pictured above are Catenary Anchor Leg Mooring System, or CALM buoys, and SOFEC is a global leader in the supply of CALM and SALM terminals globally. “SOFEC Inc. has manufactured and delivered a total of 44 CALM buoys to date,” said Claude Signori, Project Manager for SOFEC. “These have been delivered and installed evenly between Latin America, the Middle East and South East Asia. The demand for CALM buoys has been fairly steady since the early 80s and is expected to remain steady for the foreseeable future.
Prior to the arrival of the offshore terminal, vessels were obliged to moor to Jetties in a harbor/port. This would mean the construction of Jetties, the addition of transfer hoses or mechanical loading arms and in most cases the expensive dredging and upkeep of channels to accept the medium to very large vessels used for the transport of liquid hydrocarbons.”
CALM is an acronym referring to Catenary Anchor Leg Mooring, and the CALM Buoy is a floating hull with a rotating head to which vessels can moor. The CALM buoy falls under the category of a Single Point Mooring (SPM) typically with a turntable positioned above the geostationary hull mounted on a roller bearing. Flexible large bore rubber hoses are used to connect the subsea pipeline to the hull. Similar floating hoses are employed when connecting the buoy to a tanker prior to transferring liquid hydrocarbons. Central to the main bearing is a product swivel which allows fluid to transfer between the geostationary hull and rotating turntable while the moored vessel weathervanes. The vast majority of Marine Terminals installed since the mid 1990s have been CALM Buoys.
While the technology is proven and accepted, demand can be tricky to gauge, according to Signori. “We have seen various increases and decreases that are very difficult to predict. These marine terminals are not market followers since delivery from concept can be 24 months or more. What we do see is a high demand for new refineries and power plants in remote regions where ports are not part of the local infrastructure. It is much less costly to develop a system using a marine terminal than building a new port or harbor.”
One advantage of the CALM buoy for the operators is the ability to locate these terminals offshore in a suitable depth of water with an easy installation of the buoy connected to shore to via a pipeline. Another advantage, the environmental signature of an offshore installation is considerably less than a shore side terminal. These two factors, coupled with an expected operating life of 30 plus years will continue to drive the future market, according to Signori. “Also, as developing countries rely on importation of crude or refined product, we continue to see an increase in demand. For instance, as India invests in relative remote areas with refineries for their internal needs, the supply of marine terminals to import the feedstock has increased. The same will be true of power plants that rely on liquid hydrocarbons for operation.”
The project was a first for Gulf Copper, and according to Fabrication General Manager Eric Callarman, it presented its fair share of challenges along the way. But he credits SOFEC, their technical expertise, experience and willingness to partner to resolve issues as they arose as helping the yard to build its best practices even further.
According to Callarman, challenges started with the schedule which demanded a 10-month production deadline. In addition, it was the largest fabrication project to date for the Port Arthur facility, and construction far exceeded simple fabrication, involving electrical, mechanical, critical machining and FAT testing. “With the help of our client, we insured our level of quality met project requirements. We look forward to utilizing this level of quality on projects moving forward.” For example, “We originally thought that the fabrication of the CALM Buoys was going to be the most difficult and time consuming portion of the project but as we started the mechanical and integration portion of this project, we quickly learned that this was actually the most difficult and time consuming.” The final challenge is one familiar to most any ship construction facility on every continent: recruiting and hiring qualified craftsman to execute the contract. In total Gulf Copper added 50 positions for this project alone. But by the account of the client, all challenges were met.
“SOFEC is very pleased with Gulf Copper’s performance,” said Signori. “The quality is very good, and financial performance solid. Some of the mentioned challenges appeared in the form of schedule challenges, but these were overcome with hard work and more than a couple long days. Nonetheless, the project met both the Owner and SOFEC expectations.
“We were interested in contracting this work on the Texas Gulf Coast,” Signori said. “We were sure the proximity of SOFEC in Houston to a Gulf Coast fabricator would provide an advantage. And given that the local fabrication would support the end user with regards to transportation and importation obligations at the final destination, it was an easy decision to try to work locally. The difficulty would be to choose the right partner.”
Gulf Copper completed fabrication of the fifth and final buoy in December 2013 and the customer took delivery in 2014. These buoys are an excellent example of the type of specialty marine fabrication that Gulf Copper executes for number of key customers in the oil and gas industry. Founded in 1948, Gulf Copper & Manufacturing Corporation is an employee-owned company that repairs and refurbishes marine vessels and offshore rigs and fabricates specialty components for the oil and gas market. The company operates strategically located shipyards, drydocks and fabrication facilities along the U.S. Gulf Coast. Gulf Copper serves the marine transportation, offshore construction and offshore drilling markets in addition to various United States government agencies.