The Surabaya Dock of 14,000 tons was a floating dry dock which served in the Dutch East Indies and Indonesia from 1916 until the late 1950s.
Context
A large floating dry dock for the Dutch East Indies In 1900, there were three floating dry docks in the Dutch East Indies. The biggest was Onrust Dock of 5,000 tons, stationed at Surabaya. A relatively new dry dock at the time was Tanjung Priok Dock of 4,000 tons at Tanjung Priok, Batavia. The old Onrust Dock of 3,000 tons was stationed at Sabang at the western extremity of the archipelago. The two dry docks on Java could service most ships visiting the island. They were capable of lifting all ships that the Dutch navy had, and it was thought that they would also be able to lift those which the navy would acquire in the foreseeable future.
The Onrust Dock of 5,000 tons had been commissioned and stationed at Onrust Island in 1880. In 1883, the dock lifted of 5,400 tons displacement. In September 1884 Koning der Nederlanden was again reported in the dock. Soon after, the dock lifted the Russian armored cruisers of 5,683 tons, and, after unloading, of 6,234 tons. It had been proven that Onrust Dock of 5,000 tons could handle all Dutch warships and even some bigger ships. In 1886 the dry dock was rebased to Surabaya.
When, in 1903, the new of 5,002 tons displacement arrived, Onrust Dock of 5,000 tons proved unable to lift the ship. Although it was known that the official capacity of the dry dock had gone back from 4,800 tons to 4,500 tons, in view of the above this was still a surprising event. Meanwhile, there were plans for a new dry dock of 7,000 tons. After consultations between the ministries for the navy and the colonies, a commission for dry dock facilities in the Indies was appointed in January 1904. Members where: the retired VA N. Mac Leod, the retired chief engineer Siebers of the Marine establishment in Surabaya, Mr. W. Fenenga of the Amsterdamsche Droogdok Maatschappij, Navy shipbuilding engineer Van Veen, and as secretary Lieutenant Schoonhoven. This commission made a report in late 1904. In December 1904, a Dutch M.P. asked the minister for the navy about a new dry dock for Surabaya. He stated the cost of docking in Singapore, and the need for independence in this respect, but nothing much happened.
In 1903, the Droogdok Maatschappij Tandjong Priok in Batavia was extremely busy. Its commercial Tanjung Priok Dock of 4,000 tons had so much work, that some of the maintenance had to be postponed. In 1905 the company got permission to erect a patent slip that could serve vessels of up to 2,000 tons displacement, which was big enough for most vessels which regularly docked at Batavia.
The port of Port of Tanjung Perak in Surabaya Surabaya was the commercial center of Java, with good connections to the interior. In the nineteenth century, this had led to the establishment of the main Dutch navy base of the Dutch East Indies at Surabaya. Meanwhile, the harbor of Surabaya was nothing more than a place to safely anchor offshore. This meant that goods had to be transloaded to ships via boats, considerably raising the cost of calling at Surabaya. In about 1909, the Dutch government therefore started the construction of a modern port known as the Port of Tanjung Perak (Dutch: Tandjong Perak). On 22 September 1910. the Droogdok Maatschappij Soerabaja (DMS) was established to manage a dry dock facility at Surabaya. It ordered Surabaya Dock of 3,500 tons, which would arrive in 1912.
A large dual-use dry dock On 1 January 1910, Onrust Dock of 5,000 tons was still the largest dry dock in the Dutch East Indies. Under normal circumstances, it would not be large enough to lift the armored cruiser , which had been launched on 15 March 1909. However, as De Zeven Provinciën displaced 6,530 tons, being too large for Onrust Dock of 5,000 tons, did not mean that she required a dry dock of 14,000 tons, i.e. more than twice the size required to lift her. There had been ideas to acquire ships that were slightly larger, but these did not even make it to the design phase. Later plans for battleships would have led to ships which would have been too wide and high for the 14,000 tons dry dock.
In effect the explanation for the size of the dry dock is straightforward. In June 1910, the -long ocean liner Prinses Juliana of , and 12,190 ton displacement was launched. She was the biggest ship built in the Netherlands up to then. She was also a ship of the Netherland Line, the main shipping line between the Netherlands and the Dutch East Indies. She was soon followed by a sister ship, Koningin der Nederlanden. The Dutch government could not ignore the appearance of these large ships. If these ships could not rely on a suitable repair facility in the Dutch East Indies, their owners might prefer to use the alternative in Singapore.
In summary: Surabaya Dock of 14,000 tons was a dry dock meant for use by the navy and merchant shipping. In the end the size of commercial ships was decisive for the size of the new Surabaya dry dock. That it became so large was caused by the plans becoming mixed up with those for the port of Surabaya. In 1903, the new dry dock would become a 7,000 tons dry dock. In 1907 there was talk about dredging the approaches to Surabaya, and the capacity of the dry dock having to become larger than was previously thought. In November 1910, the Minister for the Colonies Jan Hendrik de Waal Malefijt presented a design for a dry dock of 120 m long and 12,000 tons lift capacity, but by then M.P.'s wanted a larger dock, because the ships of the Nederland Line and others were larger (see Prinses Juliana above).
In December 1910, Minister de Waal Malefijt then appointed a commission that was to decide on the type and size of the dry dock. The East Indies would meanwhile have to make plans for the mooring place (Navy base or new port of Surabaya) and the management of the dry dock. If the commission would advice something much more expensive than was envisioned up to then, the minister would get back to the House of Representatives. The commission consisted of: Mr. de Jongh, ex-director of the Public works of Rotterdam (chair); jhr Op ten Noort, member of the board of the Nederland Line; D. Goekoop, chairman of the society of the Dutch shipbuilding industry; Mr. Kloos, chief engineer of Nederlandsche Fabriek van Werktuigen en Spoorwegmaterieel; Fenenga, manager of Amsterdamsche Droogdok Maatschappij; Mr. C. Nobel, manager of Rotterdam Public Works, and future manager of Tanjung Perak; Lt-Captain Umbgrove; and Mr. van Beek, chief-engineer and director of navy ship construction. Meanwhile 500,000 guilders for the dry dock were put on the 1911 budget for the Dutch East Indies.
Construction and characteristics
Ordering and construction
The overall design and construction of Surabaya Dock of 14,000 tons was led by W. Fenenga. In May 1911, construction was tendered on behalf of the Ministry of the Colonies. It was to be a self-docking dry dock of the 'bolted sectional' type. The three sections of almost equal length were to be joined on the whole profile of the dock. Length was to be 140 m, width on the inside 25 m, width on the outside 35 m. The sides above the water were to be 116 m long. These were high 10 m above the pontoon deck, 4.5 m wide on the pontoon deck, and 2.8 m wide at the top. The pontoons had a depth of hold of 4.6 m in the center. The dry dock would be powered by electricity. It should be able to lift a ship of 14,000 ton displacement and 7.5 m draft in four hours. It would be delivered and tried where built, and be towed to Surabaya. Delivery date would be in June 1912. The tender was won by the Nederlandsche Scheepsbouw Maatschappij in Amsterdam.
The NSM had recently proven her capabilities with regard to dry dock construction by building Juliana Drydock of 12,000 tons. Juliana Dock had been built at a special construction site on the northern shore of the IJ. With her dimensions, she would not have been able to reach the IJ from NSM's shipyard, because the Oosterdok Lock was too narrow. As she was made for the Amsterdamsche Droogdok Maatschappij, her dimensions did not matter with regard to reaching open sea. She would be used in the direct vicinity. Using the same construction site for Surabaya Dock of 14,000 tons was not possible. In order to reach open sea, she would then have to pass either the Oranje Locks of 17.5 m width, or the 25 m wide Middle Lock of the IJmuiden Locks.
The only alternative to transport such a wide dry dock from Amsterdam to the North Sea, was to tow it over the Zuiderzee. A special construction site was therefore built near Schellingwoude on the , east of the Oranje Locks. Before construction could begin, 1,200 piles were driven into the ground as a foundation to support the huge weight of the dry dock, and that of the cranes and machines needed for construction. A steam engine with dynamo was set up to provide power to the site for lighting and driving tools. A high-pressure steam compressor was brought in for pneumatic drilling and riveting, a low pressure steam compressor was brought in for abrasive blasting. Two big gantry cranes were erected, as well as temporary buildings for storage, lunchroom etc.
Characteristics Surabaya Dock of 14,000 tons was of the 'bolted sectional' type, and made of Siemens Martin steel. Its three sections could be taken apart, so one section could be lifted by the other two for maintenance. The sections were solidly connected with bolts, rivets and rubber linings. This was done at extra reinforced connection compartments. It made self docking a tedious procedure, which made the dry dock unavailable for quite some time.
The bolted sectional type was an improvement over the previous pontoon dock, e.g. Tanjung Priok Dock of 4,000 tons, which had sides in one piece. The pontoon dock was self-docking, because pontoons could be taken out from under it for maintenance, while they were replaced by others. This gave practically no down time for the dock. The bolted sectional type had more rigidity, with the advantage of lifting ships more evenly.
Another maintenance aspect was the use of bituminous enamel coating, which had also been applied to Surabaya Dock of 3,500 tons. It was used up till the waterline on the outside, and overall on the inside, and protected the dry dock against corrosion. The coating was supplied by William Briggs & Sons Ltd. from Dundee, Scotland. During the first self docking in 1921 the coating was proven to be very effective. There was little biofouling on the hull. Most of it was seaweed that was easily removed. In between the seaweed, many mussels had attached themselves to the hull. In places where the coating had been damaged, by sunlight or concussion, these mussels had caused rather deep pits in the hull. There were about 400-500 pits on each section. These were closed by welding. There was no need to replace plates.
The dry dock was long. Beam was The sides were wide on the pontoon level, and wide on top. The depth of hold of the pontoon ranged from on the sides to in the center. The total height on the sides was . Maximum draft was At the time. Dutch shipbuilders often used English feet for measurements.
Each of the three pontoons was divided by three lateral bulkheads. The total connected pontoon also had eight traverse bulkheads in addition to the two sectional endings. This way the pontoon was divided in 4 times 11 (44 total) watertight compartments. The main frames were positioned apart. In between, there were lighter frames placed apart. The pontoon had extra reinforcements below the blocks, and where the other sections of the dock would be during self-docking.