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As a crowning generally means a bulging deformation. The result is also known as crowning for cylindrical objects such as barrels . The crowning is mainly done by machine, but also in free handicraft work such as driving .

Examples of metal processing:

  • For sheet metal : arching deformation to increase rigidity . Wafer embossing is an alternative method for stabilizing flat metal sheets .
  • In rolling mill technology : The targeted barrel-like, convex thickening of the rollers towards the center to compensate for the deflection of the rollers. In the case of rollers with a purely cylindrical shape, their deflection means that the rolled workpiece is thickened in the middle instead of the roller .
  • When folding or bending (sheet metal, etc.): A targeted curvature of the bending tools over their length in order to compensate for the deformation of the lower or upper beam that occurs during the bending process. Without such a compensation, the parallelism of the upper and lower tool would not be maintained during bending, with the result that the bending angle achieved would vary across the bending line.
  • For sheet metal deep drawing: An adjustment of the deep drawing tool - especially necessary when deep drawing flat parts - so that the deformation of the sheet metal takes place beyond the desired extent in order to compensate for the springback of the workpiece. The determination of this change according to type and size requires a high computing effort.

Also in the manufacture of jewelry, with various tools and with optical lenses one speaks of crowning.

Pressure vessels are usually manufactured as cylinders with outwardly curved end caps.

In the case of carbonated beverage cans , the base is cambered inwards in order to increase the pressure stability. A level floor would bulge outwards at the latest due to the pressure build-up when shaking. The inward curvature also ensures that the cans stand securely.

The bottoms of saucepans and frying pans are slightly cambered inwards, because the temperature gradient during heat transfer , and in the case of pressure pots, also the pressure, lead to an outward curvature. With classic electric stoves, the floor should be as flat as possible for good heat transfer .

The term is also used in belt manufacture. Cambered belts consist of an upper and a lower layer (leather or synthetic leather), between which a third layer made of another material is worked in so that the upper layer appears arched or raised.

In the case of trains, subways or trams, cambering is used when the side walls of a car are curved outwards above the entry threshold in order to create more space inside. Examples of this are the BVG series IK of the Berlin subway or the 4th generation cars of the Copenhagen S-Bahn .

In the case of spherical columns, the central arch is called entasis .

See also