BiegeRadius

Biegeradius, or bend radius, is the radius of curvature of a bend in a flexible component such as a pipe, tube, hose, or cable. It describes the smallest radius to which the item can be bent without incurring damage or functional impairment. The concept applies across mechanical, hydraulic, electrical, and civil engineering.

Material and geometry influence the minimum bend radius. Factors include material ductility and strength, wall thickness, cross-section shape, and temperature. Bending more tightly concentrates stress and can cause kinking, cracking, wall thinning, or fatigue, especially in thin-walled tubes or stiff hoses. For cables and hoses, internal fittings and reinforcement also affect bend behavior.

Specification: In design practice, manufacturers and standards specify a minimum bend radius. It is often expressed as a multiple of the component diameter (for example, 3D, 5D). Hoses, cables, and elastomeric tubes may require larger radii to prevent collapse or buckling. For metal pipes, bend radii vary with material, wall thickness, and bend angle; tight bends reduce flow and may require annealing or special forming.

Measurement and testing: The bend radius is measured along the centerline of the curved segment. Testing may involve tracing the bend with a radius gauge or mandrels, and verifying performance under operating conditions such as pressure, vacuum, or mechanical load. Standards may specify permissible deviations.

See also: Radius of curvature; Bend (engineering); Piping; Hoses; Cables.