Vibratory Stress Relief

WEMCO now offers VSR services in house and mobile to all of its customers. Our VSR-8000 system performes to Boeing standards as is Boeing approved equipment. VSR is a non-thermal stress relief method used by the metal working industry to enhance the dimensional stability and mechanical integrity of castings, forgings, and welded components, chiefly for two categories of these metal workpieces:

  • Precision components, which are machined or aligned to tight dimensional or geometric tolerances.
    Examples include machine tool bases or columns, components of paper mill, mining equipment, or other large-scale processing machinery, and centrifuge rotors.
  • Heavily loaded metal work pieces, which are components designed and built with the ability to withstand heavy loads.
    Examples include lifting yokes, clamshell buckets, crane bases, vibratory screening system frames, ingot processing, and rolling mill equipment.

These stresses reside within the metal work piece caused by rapid, unequal cooling. This occurs during welding, casting, forging, rough machining or hot rolling. These stresses often lead to distortion or warping of the structure during machining, assembly, testing, transport, field-use or over time. In extreme cases, residual stress can cause structural failure.

The theory behind this technology is to use the work piece’s own resonant frequency to boost the loading experienced by induced vibration, so to maximize the degree of stress relief achieved. Studies are proving resonant frequency vibration to be more effective than thermal stress releif.

WEMCO has experienced improved machinability of large parts such as this weldment below. Below you will see one of our factory certifed VSR operators moritoring results on the live feed graph charting results through an accelerometer.


Call today to schedule VSR services, or receive more information regarding this technology 509-244-4773