With over 550 vessels in service, Tidewater, Inc., is by far the world's largest offshore oil service operator. Headquartered in New Orleans, La., Tidewater operates wherever offshore oil and gas is found.
While the industry has undergone a slow down in 2002-03, Tidewater is confident that current trends indicate business will improve and the company has been upgrading its fleet of vessels to meet customer needs.
"We have a very strong balance sheet," said Stephen Dick, Executive Vice President of operations for North America, North Sea and West Africa for the company. "We have been moving aggressively in the area of new vessel construction, especially U.S. flagged supply boats and crew/supply vessels," Dick added.
Tidewater "sat out" some of the earlier rounds of boat building a few years ago and Dick thinks his company's strategy was right. "Many of our newest vessels have been delivered in the last six months and the balance will be in the fleet by the end of the year, just when we think the market will begin to rebound," Dick said.
In the Gulf of Mexico (GOM), the gas business looks especially strong in the near term. "The prices for the product have improved, existing supplies are being drawn down and technology is helping the oil companies to drill very deep wells on the shelf where a substantial quantity of gas my be extracted" Dick said.
These trends point to increased drilling activity, Dick believes and with additional rigs at work, the need for supply vessels and crew/supply boats rises as well.
Investing in Crew/Supply Boats
About 18 months ago, Tidewater management decided to expand and enhance its crew/supply boat fleet. They purchased 10 vessels from Crewboats, Inc., and embarked on a program to add 11 newbuild crew/supply vessels to their holdings. A part of the deal with Crewboats Inc. was the purchase of the contracts for four newbuilds from Breaux Bay Craft, Loreauville, La. They also bought an existing crew/supply boat that C & G Boat Works Inc. Mobile and Bayou La Batre, Ala. had under construction for its sister company Graham Gulf and signed a contract with C & G Boat Works to build four 175-ft. "Fast Supply" vessels.
To date, Breaux Bay Craft has delivered the 152- x 29.5-ft. crew/supply vessel Debbie Tide and a 162-ft. vessel Sandra Tide and will deliver the remaining two 162-ft. crew/supply vessels by the end of 2003. .
The Breaux Bay Craft vessels for Tidewater are all powered by a quartet of Caterpillar 3512 engines developing 5600 total hp. Caterpillar also supplied a pair of 75 kW 3306's as gensets and a third 3306 to drive a Thrustmaster bow thruster.
The 10 ft. of extra length for the Sandra Tide and her two sisters accounts for more cargo carrying capacity on deck and in below deck tanks.
Both size vessels are certified to carry 72 persons at 26-knots maximum speed.
The four vessels under construction at C & G Boat Works represent a major departure in crew/supply boat construction in that they are a hybrid between an aluminum crew/supply boat and a steel-hulled supply vessel. Called a "Fast Supply" boat by Tidewater, these vessels retain the aluminum hull and basic profile of a crew/supply vessel, but are the first aluminum-hulled vessels with below deck tanks for liquid mud.
The Tidewater concept for these vessels was incorporated into a design by Tim Graul Marine, Sturgeon Bay, Wisc.
At 175 ft. by 34 ft., this series of four vessels is also among the largest afloat. The first vessel was completed in February and is named the Vicki Tide. Power is from four Cummins KT-50 engines for a total propulsion horsepower of 7200. These engines work into Reintjes two-speed gears driving Nibral four-bladed props.
A pair of Cummins 6CTA engines drive 160 kW generators. A 250 hp Rolls Royce bow thruster is driven hydraulically. Top speed of the vessel is 23 knots. At 15 knots, the Vicki Tide has a range of 1,940 nautical miles.
As noted earlier, the below deck tanks hold almost 1,000 barrels of liquid mud. Other capacities include 25,880 of cargo water, 33,900 gallons of fuel oil
and 1,500 gallons of potable water. The vessel is also set up to carry 3,000 cu. ft. of dry bulk material on deck. The air compressor, power source and associated equipment for this system is located below deck.
Cargo deck capacity is 365 long tons. The Vicki Tide can carry a mixture of on deck cargo or bulk and below deck fluids including liquid mud up to her deadweight of 555 long tons.
First class reclining bucket seats for 36 passengers are included in the main deck cabin. Among other advanced features of this vessel is dynamic positioning rated DP-1 by ABS.
"I believe these vessels will set the standard for how future fast supply vessels in the oil service industry are designed and utilized," Dick said. "This vessel has the speed, capacity and the versatility to be used on a variety of projects. We believe our customers are going to be very pleased with how they perform, "Dick added.
The two 162-ft. crew/supply boats under construction at Breaux Bay Craft and the three 175-ft. fast supply boats abuilding at C & G are all scheduled for 2003 delivery. At that time, Tidewater will have a fleet of mostly new state of the art crew/supply and fast supply vessels.
Three Shipyards Building
Tidewater has contracted with three shipyards to build supply vessels including Quality Shipyards in Houma; La. that is owned by Tidewater. These vessels range from 207 to 260 ft. long. The one consistent thing that all 17 of the new builds have in common is Z-drive propulsion featuring Caterpillar 3516 diesel engines. "Z-drives makes sense to us," said E. J. Hebert, VP of technical services for Tidewater. "Optimum maneuverability around rigs is a critical design element in today's OSVs and Z-Drives gives us the ability to put our new vessels where the rig operator wants them and our DP-1 or DP-2 systems allows us to hold station, another critical factor for our customers," Hebert added.
Quality delivered three of a series of four 260-ft. by 60-ft. by 24.6-ft. platform supply vessels in 2002 and the fourth vessel in March of 2003.
The Miss Jane Tide, Damon B. Bankston, Paul W. Murrill and Ken C. Tamblyn are all diesel electric drive vessels utilizing four Caterpillar 3516B engines producing 10,200 hp. Each engine drives a 1,800 kW KATO generator energizing a split bus. The propulsion power is setup so that two Lips stern azimuthing thrusters in kort nozzles are each powered by a trio of General Electric motors. Azimuthing stern thrusters are often referred to as Z-drives.
In addition, there is a Lips Azimuthing drop down bow thruster and a Lips tunnel bow thruster, each powered by a 1200 hp electric motor. These two bow thrusters are needed components in a DP-2 system.
Actually the four main propulsion engines are also a part of the DP-2 system. ABS regulations require a DP-2 system have the ability to hold the vessel on station in case of a single point failure.
"Redundancy is a key to the design of these vessels," said Luis Sanders, assistant manager of new construction for Tidewater. "We have built in a great deal of redundancy in our power generation system and in thruster propulsion which is a key to operating in the harsh conditions found in deep water," Sanders added.
The engine room also has a 350 kW "harbor" generator powered by a Caterpillar 3406 engine. This generator is used for ship's power when the vessel is not at work. This series of platform supply vessels has enhanced fluid and cargo carrying capacities including 331,500 gallons of cargo water, 343,300 gallons of fuel oil and nearly 53,000 gallons of potable water.
Liquid mud capacity is over 8,000 barrels and four on deck bulk tanks can hold 11,300 cubic ft. of dry material. The actual liquid mud carrying capacity of the vessels can be higher if the customer desires.
"On a recent job, a customer needed 12,000 barrels of liquid mud so we able to add four 1,000 barrel tanks to the deck and with the below deck tanks full, the customer got the mud he needed on a single trip," Dick said.
"With a deadweight of 4,006 long tons, the 260-ft. series of vessels can haul tremendous loads into the deepest part of the Gulf," Dick added.
Tidewater's new construction program is building vessels to work deepwater, the deep shelf and the shelf. "One of our main assets is that we have a variety of vessels tailored to meet a wide variety of customer needs. "If you need a vessel with 3,000 barrels of liquid mud, we have it. If you need more, up to 12,000 barrels in a single vessel, we can answer those needs as well," Dick remarked.
In keeping with a wide range of vessels to meet varying customer needs, Tidewater is also building a three 220-ft. by 46-ft. by 17-ft. vessels with 4,700 barrels of mud capacity at Quality Shipyard. To be called the Broussard Tide, the Solar Tide II and one unnamed as of yet, these vessels are ideal shelf or even deep shelf work with a total carrying capacity of 1,872 deadweight tons. All three are powered by Z-drives and all are rated DP-1 by ABS.
A pair of Caterpillar 3512 B engines produces a total of 4520 hp. This power drives a pair of Z-drives with Rolls Royce Kort nozzles. Three 190 kW gensets produces ship's power and a 60 kW unit is used in a standby mode. A combination tunnel and drop down thruster at the bow is powered by a 1000 hp engine. Mud carrying capacity is 4,731 barrels in below deck tanks and fuel oil and rig water capacities are 124,000 and 114,000 gallons respectively. Dry bulk capacity is over 8,000 cubic ft. in five tanks.
As noted above, Tidewater has moved outside of its own shipyard to build several new OSVs. For example, Bender has recently built three 220-ft. supply vessels for Tidewater, the Collins Tide, Ed Kyle and the Pattarozzi Tide with three more under construction, the slightly smaller Lousteau Tide at 207 ft. by 53 ft. by 17 ft.
All six are 220 ft. by 54 ft. by 20 ft. and have a deadweight carrying capacity of 2,769 tons. The vessels have tanks for 270,000 gallons of cargo water, and nearly 211,000 gallons of fuel oil. Mud tanks can hold 4,000 barrels of drilling fluid. Clear deck space is 150 ft. by 45 ft. and 1,200 long tons of cargo can be carried.
Once again Caterpillar 3516 B engines are used in a Z-drive arrangement for propulsion power and Caterpillar engines are used to drive three 260 kW gensets and a 99kW standby generator. Two bow thrusters are powered by Caterpillar 3508 diesel engines.
Among the most innovative vessels being built by Tidewater are a series of four supply boats now under construction at Bollinger Shipyards, Lockport, La. Although only 207 ft. long, these vessels will be able to carry over 6,000 barrels of liquid mud, along with 131,000 gallons of drill water and 127,300 gallons of fuel oil. Deadweight tonnage is 2278 long tons.
Power setup is similar to the other supply boat newbuilds. A pair of Caterpillar 3516 B engines power Z-drives while three Caterpillar 3306 engines power 190 kW generators. A drop down bow thruster is powered by a Caterpillar 3508 engine.
These vessel feature touch screen controls to active valves and pumps for the various liquid delivery systems as well as a touch screen alarm, control and monitoring functions. Three separate pumping systems can deliver separate drilling fluids without cross contamination.
Deliveries are scheduled between October 2003 and May 2004.
"In the long run, the composition of our fleet is controlled by our customers," Dick said. "Drilling technology is calling for more liquid mud and we have been responsive to that need in our new construction program," Dick added.