Weld Shrinkage Calculator

Estimate transverse and longitudinal shrinkage for planning allowances.

Coefficient of thermal expansion affects shrinkage

Typical Shrinkage Values

Joint Type Transverse Longitudinal
Butt (V-groove)1.5-3 mm0.5-1 mm/m
Butt (Square)0.5-1.5 mm0.3-0.8 mm/m
Fillet (Single)0.3-0.8 mm0.2-0.5 mm/m
Fillet (Double)0.5-1.2 mm0.3-0.7 mm/m

Understanding Weld Shrinkage

Transverse Shrinkage Formula (Butt Welds)

Delta = 0.2 x Aw / t + 0.05 x d (where Aw = weld cross-section area, t = thickness, d = root gap)

Types of Shrinkage

  • Transverse Shrinkage: Contraction perpendicular to weld axis - most significant
  • Longitudinal Shrinkage: Contraction along weld length - typically smaller
  • Angular Distortion: Rotation about weld axis due to uneven heating
  • Rotational Distortion: In-plane rotation at joint ends

Shrinkage Control Methods

  • Pre-setting: Set parts with reverse distortion before welding
  • Restraint: Use fixtures to resist movement during cooling
  • Balanced Welding: Alternate sides to balance shrinkage forces
  • Backstep Sequence: Weld in opposite direction to progression
  • Preheat: Reduces temperature differential and shrinkage stress