Torpedo bulkhead
A torpedo bulkhead is a piece of armor that was common on all heavy warships in the early 20th century, including battleships and battlecruisers in particular . For the first time, a torpedo bulkhead was installed on the French coastal armored ship Henri IV. As early as 1898, and the Zessarevich , built on Russian orders , also received such a passive protective device.
However, in the early types of bulkhead, the expansion space for explosion gases was too small; H. the distance between the bulkhead and the actual hull did not have enough expansion space to accommodate the detonation wave of a hitting underwater projectile without damage, so that its effectiveness was very limited. It was not until the Imperial Navy introduced this type of highly effective underwater protection after lengthy and cost-intensive tests, starting with the large cruiser SMS Blücher . All later German battleships and battle cruisers were protected in this way.
The bulkhead's task was to locate or limit the ingress of water in the event of a torpedo hit. By counter-flooding , the list could be leveled out again if the damage was not too serious. After the findings from the First World War , many important ships were converted to two, three or even four torpedo bulkheads. In addition, bulges were made on the outer edge of the ship, the so-called torpedo bulges , which, however, increased the flow resistance and reduced the speed.
The last battleship plans of the US Navy in World War II, for example, had a triple floor and up to four torpedo bulkheads. The innermost bulkhead is also called the "holding bulkhead" and is usually made of stretchable steel. The outermost bulkhead was always at least 37 mm thick and is often called armored bulkhead because it could stop shrapnel at low speed. In contrast, the German system consisted of an unarmoured longitudinal bulkhead (Wallgang bulkhead) and parallel armored longitudinal bulkhead (the torpedo bulkhead) running parallel behind it at some distance, the gap between which was stiffened differently.
The space between the ship's wall and wall sheet was used as an expansion space, while the space between wall bulkhead and torpedo bulkhead was filled with coal / oil. This combination was supposed to absorb and withstand the pressure of an explosion (which worked on German ships both in the First and Second World War in such a way that serious damage was avoided and floatability was retained - e.g. on the large cruiser SMS Seydlitz nach the Skagerrak Battle ).
literature
- Charles Gillmer, Bruce Johnson: Introduction to Naval Architecture. Naval Institute Press, Annapolis MD 1982, ISBN 0-87021-318-0 .