Alternating Current Field Measurement (ACFM)

alternating current field measurement
Alternating Current Field Measurement (ACFM) is an electromagnetic nondestructive testing technique that has been developed to provide an incredibly efficient way to retrieve reliable crack detection data.

ACFM introduces an alternating current into the surface of a material to detect surface-breaking cracks. The uniform current acts like a thin skin that wraps around a component. If a crack is present the skin ruptures and the current sends a signal back to the instrument which translates into crack length and depth.

Features of Alternating Current Field Measurement
  • Ideal for In-Service Inspections
  • Noninvasive
  • Requires minimal surface preparation
  • No paint removal
  • Portable
  • Capable of performing at high temperatures
  • Offline data analysis
  • Detects crack length and depth
  • Ideal for large test specimens

Applications of Alternating Current Field Measurement
  • Weld inspection
  • Offshore structure inspection
  • Aerospace component inspection
  • Pressure Vessels and Storage Tanks in oil and gas or power generation industries
  • Automotive component inspection
  • Components with complex geometries

Applied Technical Services is now offering 40 hour Level I and Level II courses for aspiring Alternating Current Field Measurement technicians. We cover the entire curriculum of the latest CP-105 as well as following ASNT SNT-TC-1A recommended practice guidelines for formal education, experience, and training. As a certified Level I ACFM technician, with employer instructions, you will be able to set up ACFM testing equipment, perform ACFM inspections, and record the results. As a certified Level II ACFM technician, you will be able to do everything a Level I is capable of plus select the appropriate ACFM technique for the test, prepare written instructions for Level I’s, and interpret and evaluate the results according to the applicable standard, code or specification.