Alternating Current Field Measurement is an electromagnetic inspection method for the detection and sizing of surface cracks. This is a non-contact technique which can be applied over coatings.
The ACFM method can be applied on different materials, such as aluminium, galvanized steel plates or thin conductive coatings. Variations in thickness can cause false signals, which can be minimized using an array of sensors.
The technique is applicable both on standard industrial applications and underwater. The ACFM method can defect defects in ferromagnetic and non-ferromagnetic materials.
ACFM‘s data analysis and reporting include the following information:
- Inspection analysis
- Operator, date/time, scans
- Locating the data files
- Probe type and serial number
- Operating frequency
- The report and data can be sent by email.
Benefits of using ACFM:
- It works through paint/coating so there is no need to remove it.
- Record all data, regardless of whether defects are found or not.
- Validation of the data received through the lift-off control (lift), establishing a quality control (QA) of the inspection.
- The equipment can be easily operated directly (one operator) or remotely (two operators).
- It can be applied in a wide range of temperatures and is adaptable to most industrial applications.
- Access to difficult areas, regardless of visibility.
- Detection and sizing of defects using a portable system.
- Weld Inspection
- Pressure vessels
- Pipe lines
- Storage tanks
- Drill Pipe Thread Inspection
- General cargo cranes
- Container Cranes
- Theme parks
- Power Generators
- Nuclear power plants
- Storage tanks
Within the wide range of applications, the inspection of high-temperature equipment can be mentioned. The ACFM method can be applied on components with up to 500ºC.
The Lizard M8 system provides impedance and phase of the magnetic field. This information allows to identify and size the depth profile of a crack.
The new LIZARD M8 can support probe cables of up to 200 meters.
- The probes have additional detection sensors which enable to verify both the coupling and the correct handling of the probe.
- This technology enables to display FGI images to identify multiple non-linear cracks and to determine the depth of the crack.
The Lizard electronics works at frequencies from 1 kHz to 1 MHz and the probes are multifrequency so a single probe can be used on both ferromagnetic and non-ferromagnetic materials therefore massively reducing the overall investment.