Radial stress

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Radial stress is stress towards or away from the central axis of a component.

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Pressure vessels

The walls of pressure vessels generally undergo triaxial loading. For cylindrical pressure vessels, the normal loads on a wall element are:

The radial stress for a thick-walled cylinder is equal and opposite to the gauge pressure on the inside surface, and zero on the outside surface. The circumferential stress and longitudinal stresses are usually much larger for pressure vessels, and so for thin-walled instances, radial stress is usually neglected.

Formula

The radial stress for a thick walled pipe at a point from the central axis is given by

where is the inner radius, is the outer radius, is the inner absolute pressure and is the outer absolute pressure. [1] Maximum radial stress occurs when (at the inside surface) and is equal to gauge pressure, or . [2]

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References

  1. "Stress in Thick-Walled Tubes or Cylinders". EngineeringToolbox. Retrieved 2012-05-18.CS1 maint: discouraged parameter (link)
  2. Benham, P.P.; Warnock, F.V. (1973). "14.4 Stress distribution in a thick-walled cylinder". Mechanics of solids and structures. Bath, UK: Pitman Paperbacks. pp. 331–338. ISBN   0 273 36191 0.