Page 4: of Maritime Reporter Magazine (April 1974)

First Semisubmersible Rig Built On East Coast

Curtis Bay tugs escort the Ocean Scout under the Chesapeake Bay bridges below Balti- more to an anchorage where the remaining sections of her drilling derrick were installed.

The Ocean Scout, the first semisubmersible oil-well drilling rig to be constructed on the

East Coast of the United States was towed from Bethlehem Steel's Fort McHenry ship- yard on February 21 to a site below the Chesa- peake Bay bridges, where final sections of the drilling derrick were erected.

The rig was then delivered to Ocean Drilling & Exploration Company of New Orleans, La.

It will be operated in the Gulf of Mexico by the Pennzoil Company.

Designed to be a mobile offshore drilling unit suitable for unrestricted ocean service, the Ocean Scout, with a lower hull length of 202 feet and width of 182 feet, was designed by Breit Engineering, Inc. of New Orleans.

The lower hull consists of two watertight structures 202 feet 'long, 32 feet wide and 28 feet deep, joined so that they are 150 feet apart on centers. Main members of the struc- ture rising from the two sections of the lower hull are four 32-foot-diameter corner stability columns and four 10-foot-diameter interior columns, all interconnected by truss work.

Atop them is the upper deck which is 170 feet long, 150 feet in width and 14 feet deep.

The upper deck is watertight and contains the machinery spaces. Overall, the rig meas- ures 108 feet from the bottom of the lower hull base line to the upper deck.

The operational draft will be 48 feet in depths of water from 80 to 600 feet. Towing is done with wire towing hawsers.

Provisions are made for carrying drilling water, fuel oil, liquid mud, cement and other drilling supplies. The living quarters, includ- ing staterooms, galley, mess, lounge, hospital, offices and passageways, are air-conditioned,

Accommodations are designed for a crew of 59.

The most modern fire-fighting equipment, as well as all necessary navigation aids are pro- vided.

About 7,000 tons of steel were used in con- structing the rig, which will tower 257 feet aibove the water when under tow. Since clear- ance under the Chesapeake Bay bridges is only 186.5 feet, the upper portion of the derrick was erected at an anchorage just below the bay bridges.

The Ocean Scout will be moored by eight 30,000-pound anchors, each with 2,500 feet of 2j^-inch-diameter stud 'link anchor chain.

The unit is capable of drilling a hole in ex- cess of 20,000 feet. Major items of drilling equipment include a 147-foot derrick, a 3,000- hp drawworks and two 1,300-hp mud pumps.

The main power plant for both drilling and vessel service includes diese'l engines with over 5,100-hp combined capability.

The sub-sea system includes a 20-inch blow- out preventer stack with a 24-inch integral marine riser and a 13^-inch, 5,000-psi blowout preventer stack with a 16-inch integral marine riser. The marine riser is equipped with a hydraulic tensioning system. An underwater

TV system is utilized to monitor and assist with sub-sea operations.

Two revolving cranes are situated aboard the drilling rig to provide loading and unload- ing capability.

SNAME Hampton Roads Section

Discusses Shipyard Numerical

Control Lofting Management

Pictured above during the meeting at the Commodore

Country Club, left to right: R.C. Strasser, vice chairman of the Hampton Roads Section; C.E. Peacock Jr., Section chairman; Thomas Lamb, author and Don Tolefson, in- troducer.

The Hampton Roads Section of The Society of Naval Architects and Marine Engineers met at the Commodore Country Club on Feb- ruary 7, 1974. C.E. Peacock Jr., chairman of the Section, opened the meeting with an in- troduction of officers and guests.

Sam Tatum gave an informative presenta- tion on the nature and purpose of.the SNAME

Technical and Research Program.

Don Tolefson introduced the principal speak- er of the evening, Thomas Lamb, who present- ed a paper entitled "The Management of Nu- merical Control Software and Its Impact on the Operation of a Shipyard."

Mr. Lamb, manager of the Marine Division of the Value Engineering Company, gave a broad discussion on several aspects of manag- ing shipyard numerical control lofting and fab- rication processes. Areas covered included technical justification for the use of numerical control devices, and a consideration of shipyard staffing and training requirements to imple- ment and operate a computer-aided lofting de- partment.

Natl Bulk Affiliate Orders

Two 268,500-Dwt Tankers

Wellington Tankships, Ltd., a Liberian affiliate of National Bulk Carriers Inc. (NBC) of the U.S., recently placed an order with IHI (Ishikawajima-Harima Heavy Industries Co.,

Ltd.), Japan, for two 268,500-dwt (or 126,500- gt) tankers.

E.L. Hann, vice president of Far East op- erations of NBC, and Dr. Hisashi Shinto, president of IHI, signed the contract worth approximately 30,000-million yen in total.

The two tankers will 'be built by I'HI's Kure

Shipyard, with completion scheduled for Feb- ruary 1978 and June 1978, respectively.

Each tanker will have a 40,000-shp IHI turbine, developing a service speed of 16.0 knots, as the main propulsion engine.

Since 1964, NB'C has ordered 29 ships total- ing 6,172,000 deadweight tons from I'HI, in- cluding three 326,000-dwt tankers, four 445,- 300-dwt tankers, and ten 270,000-dwt-class tankers of the same type.

Iraq Orders 4 Tankers

From Gotaverken Yard

Gotaverken, Goteborg, Sweden, has received orders for four 154,000-dwt tankers from the

Iraqi National Oil Co., Baghdad, Iraq.

The ships are to be built at Gotaverken's

Arendal Yard, and are due for delivery in 1977.

They are the latest addition to a series of 32 similar tankers, the first of which is now being built at Gotaverken, and is to be deliverecl in

June.

N.Y. PROPELLER CLUB PRESENTATON: Copt. Adrian

P. Spidle presents Liberty ship model to Albert Parente, president, Brotherhood of Marine Officers. Left to right:

Col. James B. Soden, (ret.), secretary-treasurer. Propeller

Club, Port of N.Y.; Captain Spidle, vice president. Pru- dential Lines, and president. Propeller Club, Port of N.Y.;

Mr. Parente, and Thomas A. King, Eastern Region Direc- tor, Maritime Administration, and vice president, Propel- ler Club, Port of N.Y. The idea of offering a Liberty ship model in return for a donation to the Hall of Ameri- can Maritime Enterprise, to be located in the Smithsonian

Institution, was conceived by Captain King to help fulfill the Club's financial commitment to the Hall. • 6 Maritime Reporter/Engineering News