Rotterdamsche Droogdok Maatschappij
The Rotterdamsche Droogdok Maatschappij (RDM), was the largest pre-World War II shipbuilding and repair company in Rotterdam in the Netherlands, existing from 1902 to 1996. It built 355 mostly major seagoing vessels, 18 of which were submarines. During its existence, the wharf operated 12 floating docks and in its heyday employed 7.000 people at one time.
RDM was established on 23 January 1902 in the Heijplaat district, located on the banks of the river Meuse (locally named 'Maas'). It was a movement of a company founded in Delfshaven in 1856 by Duncan Christie.
On 14 January 1925, a shipbuilding facility was set up as a subsidiary on the northern bank in Schiedam and continued to function as a separate establishment until 1978.
In 1928/29 the so-called 'Onderzeebootloods' (submarine hall) was built. This was enlarged three times. Here, 17 Dutch and 1 Polish submarine were constructed. Two of the subs fell into German hands in May 1940, and duly served in the Kriegsmarine, the navy of Nazi Germany. The Germans also found the snorkel here, a Dutch invention. This apparatus allows subs to use their diesel engines under water, greatly extending their range, and subsequently all German U-Boats were equipped with this. The hall is now part of the so-called RDM Campus, a combination of research and development companies and a college.
World War II
During World War II, the company fell into German hands undamaged and intact, regardless of having been a major arms supplier to the Royal Dutch Navy. The management decided to continue business as usual, although the representative of Queen Wilhelmina (who herself had fled to the United Kingdom), General Henri Winkelman, expressly forbade any work on German military projects. Work on Dutch military products could be continued.
A secret policy of clandestine opposition and dragging of feet was developed in the first months of the war, with the full support of the management. The main goal was to protect the work force from deportation. In 1942 nevertheless, some 250 men had to go and do forced labour ('Arbeitseinsatz') in Germany, for shipbuilders Blohm und Voss in Hamburg. Wartime production achieved only half that of peacetime. After the war, none of the directors were indicted for collaboration.
In total the RDM completed 32 vessels during the war, 24 of which were smaller war ships for the Kriegsmarine. The shipbuilding company became an accepted target for the Royal Air Force, and in 1941 a German ship under repair was sunk in an air attack, with two people killed. No substantial damage to the wharf was done by the Allies during the war.
However, after the start of Operation Market Garden on September 17, 1944, the Nazi German occupiers in the Netherlands decided to destroy all major ports, port facilities and infrastructure in the Netherlands. As a result, he RDM was nearly completely wrecked: the floating docks were ravaged and sunk and all major cranes blown up. The Germans also looted any production means such as lorries and lathes and took away any remaining supplies. Within six months following the end of the war, four floating docks were salvaged and repaired.
After the war
On 4 March 1966, in a merger with Koninklijke Maatschappij De Schelde and Motorenfabriek Thomassen led to the creation of Rijn-Schelde Machinefabrieken en Scheepswerven (RSMS), and a further merger on 1 January 1971 with Verolme Verenigde Scheepswerven (VVS) led to the united company of Rijn-Schelde-Verolme Machinefabrieken en Scheepswerven (RSV).
On 6 April 1983 the bankruptcy concerning RSV and RDM was announced. The offshore department was closed and the repair department transferred to Wilton-Fijenoord, by means of sale of the two largest docks. Of the 3,180 employees, 1,370 people became unemployed. The still viable components, the naval and the tool and heavy machinery businesses, were categorised in a new company: RDM Nederland BV, property of the government
Naval construction got a large boost by the orders for Walrus-class submarines for the Royal Netherlands Navy. However, the proposed supply of submarines to Taiwan failed to materialize, in part due to political implications. As ship building orders declined, and the company became more involved in high technology systems development for the military and energy sectors, the name of the company was again changed, this time to RDM Technology. The naval section eventually became Damen Schelde Naval Shipbuilding, owned by the Damen Group.
On 20 December 1991, the company was sold by the government to the Royal Begemann Group of Joep van den Nieuwenhuyzen, and renamed RDM Technology Holding BV. Due to a lack of orders, employment was cut from nearly 1,200 to under 500 during reorganizations in 1993 and 1994, while the departments were divided into RDM Technology BV and RDM Submarines BV.
In 1996, these companies were privately obtained by van der Nieuwenhuyzen. They were used for several activities and financial operations in the weapons industry, but no longer in association with the company's original shipbuilding activities. The shipyard itself was eventually acquired by the city of Rotterdam.
The primary business of RDM had always been ship repair in its drydock facility, although it also built several new vessels over the years. The company also became a strong competitor in building equipment for offshore drilling by the mid 1960s.
Ships built by RDM include:
- De Zeven Provinciën-class cruiser:
- Walrus-class submarines
- Passenger ships
Reactor vessels for nuclear plants
Rotterdam Drydocks built 22 reactor vessels for nuclear plants all over the world. These include:
- The Netherlands:
- Borssele (1 reactor)
- There are further for reactors in: Argentina (1), Germany (2), Spain (2), USA (10), Sweden (1) and Switzerland (2).
In the Belgium reactor vessels numerous tiny faults have been found during the 2012 maintenance inspections, with unknown consequences for the near future of these two reactors. 
|Wikimedia Commons has media related to Rotterdamsche Droogdok Maatschappij N.V..|
- Honderd jaar Rotterdamsche Droogdok Maatschappij (100 years of RDM) (in Dutch)
- RDM on the Dutch Wikipedia
- RDM on the Dutch Wikipedia
- Le Hir, Pierre (9 August 2012). "Soupçons sur les cuves de 22 réacteurs nucléaires". Le Monde (in French). Retrieved 29 March 2015.