The birth of the bulker
Authored by: American Bureau of Shipping's Surveyor
Brought to you by www.dieselduck.net, comments to [email protected]
The thousands of ocean-going dry bulk carriers in service today still reflect the practical design of Cassiopeia, their archetype.
The role of such legendary shipowning entrepreneurs as Daniel Ludwig and Stavros Niarchos in creating the modern crude oil carrier, Malcolm McLean the containership and Erling Naess the OBO are well-documented chapters of modern maritime history. These vessel types were developed to serve a pressing commercial need, and have spawned worldwide fleets of modern vessels that are not substantially different from their archetypes. One lesser-known chapter of the same history was written by Ole Skaarup, who can claim to have had the major part in creating the modern dry bulk carrier as we know it today.
Today, nearly 7,000 bulkers are at sea, carrying ore, rock, pulp, coal, grains, and other cargoes. But in 1955, purpose-built dry bulkers did not exist (though ore-oil carriers had been introduced). General bulk cargoes were mostly carried in converted Liberty Ships and surplus tonnage.
Ole Skaarup began Skaarup Shipping on a shoestring budget in 1951. By 1954, the small ship brokerage firm was fixing ships for a number of shipowners and shippers of bulk cargoes. One January day that year, sitting in his office at 21 West Street in New York City, Skaarup began thinking about the vessels that bulk shippers had available to them.
A Logical Design
Oil-ore carriers were fine, he thought, but you can't use them for coal or grain because you don't have sufficient cubic capacity. The rest of the available fleet consisted of Liberty Ships and a variety of 'tweendeckers. Coal and rock cargoes were often stowed in the 'tweendeck, and the shaft tunnel amidships made discharging a nuisance. This was inefficient enough, but hauling grain could be a nightmare.
Before loading grain into a Liberty Ship, you first needed to install grain fittings or "shifting boards" - an awkward arrangement of wooden frames, beams and boards designed to stop the grain from running into the vessel's wing spaces or shifting during transport and wreaking havoc with stability. Atop the shifting boards were bins or "grain feeders" designed to ensure that the holds were completely full.
Constructing this plywood labyrinth took a team of carpenters several days' worth of valuable time, and cost about $10,000 (in 1954 dollars)! To make matters worse, if the return cargo was coal (or anything but grain), another team would have to come aboard and tear the whole arrangement down - for another $10,000. Furthermore, most available vessels had machinery amidships occupying the ideal place for heavy, high-volume cargo.
To Skaarup, it seemed that the most practical ship should have wide, clear cargo holds. Thus, it would require machinery aft, wide hatch openings to ease cargo handling and a hold configuration that could eliminate the need for shifting boards. To make the hatches acceptable as grain feeders, they would have to extend several feet above deck.
He began making sketches on a notepad. He knew that a hold filled with grain had two large air spaces at its top corners, because the grain pile sloped downward from the hatch opening to the wall of the hold. The grain tended to shift during transport. The key to the design, he reasoned, would be sloped wing tanks in the upper part of the hold that would carry ballast and also fill this void. He sketched out a midship section. "Dammit!," he exclaimed, "This is the way to do it!" Then he made a proper drawing and took his idea overseas to some well-respected associates.
Sold For A Song
Working with Swedish shipowners Nordstrom & Thulin, Skaarup finally realized his idea. "But," he adds, "the man to whom I sold the idea was not from Nordstrom and Thulin. He was Marcus Wallenberg, the greatest Swedish industrialist ever." The head of Stockholm Enskilda Banken, Wallenberg had major holdings in such companies as Asea, Stora Kopparberg, Atlas Copco, Saab Scania, Electrolux, L.M. Ericsson and SKF.
Nordstrom & Thulin, a long-established shipowner, had been among Stockholm Enskilda Banken's first customers nearly a century before. So 90-year-old Mr. P.G. Thulin, the firm's patriarch, introduced Mr. Skaarup to Mr. Wallenberg. The two men began what was to become a lifelong, productive friendship. "In order for Wallenberg to find out whether I was really genuine, he put me through a little test," recalls Skaarup. "I had told somebody that I was a saxophone player from way back, and that I had had a band back in Copenhagen. Well, I was out to dinner with these bankers and, sure enough, somebody brought in a saxophone to check me out. Fortunately, I was a pretty good sax player at the time; I blew them a few tunes and that established my credibility."
Skaarup explained his concept to Wallenberg, who accepted his reasoning and agreed to collaborate on the development of the vessel. "Marcus Wallenberg was a man of decision," Skaarup recalls with fondness and respect. "I said 'this is the way these ships should be built' and he said 'Let's order one.'" The contract for the first purpose-built, oceangoing dry bulk carrier - then referred to as the OS-type design - was signed with the Kockums shipyard on 22 March 1954.
As often happens with new ideas, basic elements of Skaarup's plan were challenged by the yard's conventional-minded engineers. "You can't steer from aft," they said. "Okay, let's put an auxiliary navigation bridge up front," answered Skaarup. "If we made hatches that big, we'd have to strengthen the deck." "So, strengthen the deck." "You should put a bulkhead in the middle of the holds for strength to serve as shifting boards." They drew it onto his plans. "No way," he answered, and crossed it out.
And so it went. Eventually, Skaarup built his OS-type vessel, with machinery aft, wing tanks to prevent cargo shifting, wide-open cargo holds with smooth sides and sloped bulk-heads to facilitate cargo discharge and cleanup, and without a center bulkhead. He conceded to an odd-looking navigation bridge about amidships, an element he never repeated. His basic design has stood the test of time. "Today there are about 7,000 ships virtually identical to the OS-type." The original plan, which still shows the crossed-out center bulkhead, is one of his proudest possessions.
The Future Arrives
"I asked the men from Kockums if I could patent this and they said 'No, it's only another way to make a ship.' That misleading advice is the saddest thing that ever happened to me," he says ruefully.
And so Kockums hull No. 407, a 19,000-dwt vessel named Cassiopeia (pictured below), was launched in 1955 at a final cost of roughly $2.5 million. It could carry ore, grain or any bulk commodity. Its economic advantages became apparent almost instantly. The cost of loading and trimming a coal cargo in a U.S. port was 50 cents/ton less with Cassiopeia than with a Liberty Ship, while the savings in discharging an ore cargo was even better. Skaarup figured that the savings in stevedoring costs alone would pay for the ship in about 10 years.
An additional bonus to Cassiopeia were savings in time, port costs and fuel over the two Liberty Ships its capacity replaced. This anticipated the "economy of size" movement that has for the last 30 years dominated bulk shipping. It did not take long for the market to realize the new ship's potential. Soon after Cassiopeia began service, Kockums sold five sister ships - three to another pioneer, Stavros Niarchos. Today, the dry bulk carrier is virtually the only type of ship engaged in the carriage of dry bulk commodities.
The Ship That Unloads Itself
Skaarup's next idea was to apply the self-unloading concept to the ocean-going bulk carrier. A gravity-type self-unloader would not need cranes, on board or ashore, nor stevedores, nor even a pier to deliver its cargo. The deeply sloping hoppers in its holds would conduct cargo to a gate at the bottom of the hold opening onto a conveyor belt. The belt would carry the cargo off to the stern, whence it would be transferred onshore via a boom conveyor extended from the ship. The holds in such a vessel would have less cubic volume than a standard bulk carrier of equivalent size, but a dense cargo of, say, less than 30 cubic feet/ton would be carried by either ship in equal amounts. One such cargo is gypsum rock.
Skaarup targeted the National Gypsum Company as the first customer for the self-unloader. The company had been hauling gypsum in three Liberty Ships. "It was an absurdity, hauling gypsum in those ships," he recalls. "It took them about a week to discharge these ships with their antiquated shore equipment.
"In 1955, I convinced National Gypsum to try my new self-unloader. That became the Melvin H. Baker, named after the company's founder and chairman."
Working again with Nordstrom & Thulin and Swedish designers Nordstroms Linbanor, Skaarup designed the Baker's holds, hatches and conveyor system. "The Baker can discharge 2,000 tons/hour with only three men working," he points out. "They just open the gates and control the unloading. You barely open the hatches, and all you see is the stream of cargo coming out the stern end of the ship."
Melvin H. Baker began service for National Gypsum Company in 1956. Still working, it makes the saltwater run from Halifax to ten ports along the U.S. east coast and the Gulf of Mexico. Apart from a new bottom ten years ago and steel renewal five years later, she has had only regular maintenance.
Melvin H. Baker has completed over 1900 trips in its 36-year career. This record is commendable, particularly in the light of bulker casualties in recent years, where ships have disappeared into the sea without a trace.
"When you see the battering that grabs and bulldozers inflict on regular bulk carriers and you see the condition of the ship's ballast tanks, it is no wonder they suffer damage and loss," reflects Skaarup. The structural stress and ensuing corrosion and fatigue failures caused by bulk cargo handling methods is currently under investigation by ABS, other classification societies and regulatory bodies.
A Timeless Design
One reason for the Baker's longevity is that no cranes, grabs, bulldozers or jackhammers are needed in unloading. But could the self-unloading design be a possible solution to some of the structural problems plaguing bulk carriers today? No doubt, thinks Skaarup. "At present," he says, "very little coal or grain is moved by ocean-going self-unloaders. This type of ship has not been so advantageous in that service because it costs so much to build, due to all the special equipment about 25% more than a conventional bulker. Primarily, though, you lose cubic volume due to the hold design. For that reason, self-unloaders have not been considered economical for long hauls.
"Right now," though, "self-unloaders are virtually the only bulk carriers used for short hauls in the Great Lakes, and I believe the time is drawing near when several trades in the ocean will convert to self-unloaders," he adds.
Bulkers today come in many different sizes. There are the "handy-size" types (up to about 25,000 dwt), so called because they are literally handy for carrying virtually any bulk cargo; some even carry containers. Larger types are: the handymax (up to about 40,000 dwt); panamax (about 60-70,000 dwt), designed to transit the Panama Canal with maximum cargo; and capesize (about 150,000 dwt), that pass around the Cape of Good Hope because they cannot transit the Suez Canal. There are behemoths such as the 260,000-dwt Athesis Ore, dedicated to one commodity on one particular run. Some open-hatch types carry pulp and paper in box-like holds. With due respect to the engineering involved in each, they are largely refinements, extensions or adaptations of a standard design. Generally speaking, that standard design still bears the signature of the ship broker and ex-musician whose idea for a new maritime workhorse helped change ocean-borne commerce.
-from the September 1992 issue of "Surveyor," the quarterly publication of the American Bureau of Shipping
Editor's Note
I received an interesting set of emails from Mr. Juan Marino regarding the "Birth of the Bulker" piece, as it appears above. He brought up interesting points and I have condensed the emails and represent them below for your information and discussion.
Martin Leduc
Martin's Marine Engineering Page - www.dieselduck.net
I read “The Birth of the
Bulker” an article brought from the Sept. 1992 issue of ABS’s
“Surveyor” publication by Martin’s Marine Engineering page (www.dieselduck.net)
where it’s emphatically said that the modern bulk-carriers design was actually
an invention of Mr. Ole Skaarup.
Naturally, anyone is
free to do it but I should say that Mr. Ole Skaarup went too far on
I wasn't surprised that Kockums had
rejected Skaarup's idea of patenting a design
Furthermore, to avoid any doubt, have a look at the pictures of SVEALAND (1925 - below), this bulker and its sister ship AMERIKALAND, owned by the Swedish Brostroms Group, were already trading between American ports in the 20's. Its configuration and deck arrangement are clear enough.
The m.s. Svealand was
built in 1925 to attend a traffic between Chile and the USEC, under a 20 year
contract with Bethlehem Steel.
On 1951 the owners of m.s.
Svealand (Brostroms) made some conversions at the
