Diamond Services Corp., based in Morgan City, La., knows the importance of staying competitive in the oilfield service industry, which is why the company broke conventional rules of "propping" and built Mr. Mel, the first waterjet-powered crew/supply boat to work in the Gulf of Mexico.
The diesel engine/waterjet combination, considered an innovative choice of propulsion system for a crewboat, offers advantages of increased speed, maneuverability and flexibility over propellers.
The 145 ft. aluminum monohull, built by Swiftships, Inc., was delivered in February 1995. At the time, Mr. Mel was powered by four 815 bhp diesels driving four Hamilton HM-571 water jets through a Twin Disc MG-5202 gear with a 2:1 reduction ratio. Mr. Mel is capable of carrying 79 passengers with a full load of fuel and 30 tons of deck cargo at 24 knots, and can achieve 28 knots light.
Since 1995, Mr. Mel has worked continuously in the Gulf of Mexico, running supplies and crewmen to deepwater oil rigs. The waterjets, as expected, have performed flawlessly, making them a worthwhile investment in the eyes of Diamond Services.
"We began experiencing engine problems," says Mike Swiber
, the company's purchasing manager. "What began as piston ring wear turned into larger, more frequent problems." Swiber says during the first three years, the engines went through several repairs and overhauls in an attempt to alleviate the problems. While much was covered under warranty, it was downtime the company could not afford.
"We continued to successfully serve our customers during these times, but the original engines weren't durable enough to meet our standards," says Swiber "It's no secret in this industry, engines take a beating, and these simply weren't cut out to be crewboat engines."
With a loss in business potentially at stake, Diamond Services decided to pull Mr. Mel's original diesel power plants. The company looked to its fleet, powered by various engine manufacturers, for clues as to which type of engine would meet the company's requirements.
The answer was found with Diamond Services' Lisa Ann and Mr. D. Lisa Ann was built in 1997 to the same specifications as Mr. Mel, but powered by Cat 3412 engines. The same year, 17-year-old Mr. D, equipped with conventional props, was repowered with the same model engines. The performance results were strong for both vessels, so Diamond Services ordered four Cat 3412 engines, each rated 825 bhp @ 2,100 rpm, from the local Cat dealer: Louisiana Machinery Power Systems.
The repower was completed in May 1998. After passing all the necessary performance tests, Mr. Mel was back to work in the Gulf the following month.
"The Cat engines have been performing very well, and they work well in tandem with the jets," Swiber says. "The engines are still pretty new, but if they have a track record like the ones in Lisa Ann and Mr. D, I expect they'll perform reliably."
Durability, comparable horsepower ratings and competitive pricing were the top reasons Diamond Services selected Cat engines for the repower, Swiber says. Availability of parts and service from Caterpillar was also an important factor for a boat that operates continuously, he adds.
"There's even a Cat dealer located in Del Cormen, Mexico, which is in the region where Mr. Mel operates
," adds Swiber.
More shipbuilding activity is on the horizon for Diamond Services. The company built the world's largest jet-drive crewboat at Swiftships Inc. Kristin Grace measures 185 ft. long and 30 ft. wide, and is capable of carrying cargo up to 330 long tons on deck, nearly twice the amount of Mr. Mel. She is designed to transport 64 passengers and five crewmen. The quad-screw vessel is powered by Cat 3508 Series B electronically controlled engines, each rated 1,300 bhp @ 1,835 rpm, driving Hamilton waterjets.