Shifting energy equations. Increasing environmental regulation. Accelerating demand for larger, multi-use ships. When it comes to designing high-performance, cost-effective diesel electric vessels, today's shipbuilders face daunting challenges. For each new challenge they face, they must find a solution that can withstand the rigors of a marine environment.
This week at the Marine Industry Forum at Automation Fair, presented by Rockwell Automation in Houston, marine industry professionals offered insight into industry trends and best practices that help drive efficiency, flexibility and productivity across a ship, address current environmental demands, and discover how to lower total cost of ownership, whether it's a private fleet or Navy transport vessels.
"The pressure to innovate is ever-present and it's growing," noted forum host Mike Tangora, business development manager, Rockwell Automation. "There are demands for constant change from all around the marine industry. The U.S. energy revolution in progress is changing traditional shipping route constraints; ports that until recently were receiving energy supplies are now exporting energy. The entire U.S. shipping distribution network is being redone in the midst of a renaissance of private American shipbuilding."
Tangora noted that oil exploration is heading into ever-deeper waters and will require larger- capacity oil and exploration and production vessels, while at the same time the cost pressure on traditional government programs is growing.
Forum speakers also made it clear that cost and performance pressures don't stop outside the gates of the U.S. military. Similar performance pressures are found there as well. "The Navy's platforms are getting older," began Johnny Walker, Capt. U.S. Navy (Ret.), and president, Thor Solutions. "They need to get to the full service life that taxpayers paid for." Thor Solutions is a technical consulting group with a range of acquisition, program management and engineering services centered on surface ship and combatant craft maintenance, training, logistics, warfare assessment, machinery controls, environmental and safety sectors within the defense and Homeland Security domains.
In early 2005, the Navy faced declining control system reliability and obsolescence in its twelve LSD-41/49 class ships, but was unable to fund replacement. "These are the ships that carry armored landing vehicles to the beach, the first ones in," Walker explained. "The heavy stuff is on the horizon waiting. If you don't have that ship that puts in the first set of armor, nothing happens. This can be a single point of failure for an operation."
The Navy embarked on the implementation of a distributed PLC-based advanced engineering control system (AECS) for these ships, based largely on ControlLogix architecture from Rockwell Automation. Now nearing completion of its few remaining installations, LSD AECS includes new subsystem controls for propulsion, electrical power management, steering and an on-board trainer (OBT). The result, Walker reported, is an energy-efficient, low-cost solution providing lowest total cost of ownership, and more dependable performance.
"Somebody asked me, what led to the decision to upgrade and refit the control systems on the ship," Walker continued. "It was the risk of a legacy system and the consequences of failure," he said, citing personal experience with a controls malfunction during an already dangerous refueling at sea operation.
The expected service life of these ships was at 40 years. "It started out at 30, then went to 35, and the next year they wanted us to make it 40, and today it's at 45 years," Walker recalled. "It's designed service life is 30." He pointed to the new installation that included Allen-Bradley Logix PACs, PanelView HMI and PowerFlex drives from Rockwell Automation, and new AC motors as the critical elements in ensuring the performance of functions such as crane operation that were single points of failure elements.