Magnetic Rescue Hoist Wire Rope Inspection System (MagSens)
The MagSens can be purchased separately or supplied as an integral part of the Hydraulic, Manual, or Electric RHGSE. Zephyr International LLC has developed and sells the only inspection system for rescue hoist cables. The MagSens system provides the rescue hoist maintainer the capability to measure and record locations of defects.
The MagSens is designed to improve the way the rescue hoist cable is inspected and to provide the ability to measure and document its condition. It uses Magnetic Flux Leakage to locate defects in the rescue hoist cable. The device uses strong permanent magnets to create a magnetic flux circuit and Hall Effects sensors mounted to magnetic flux concentrators detect variations in the magnetic flux circuit that result from local faults (LF) or loss of magnetic area (LMA).
Magnetic Flux Leakage inspection has been used for over 50 years for the purpose of cable inspection in deep mines and in the offshore oil industry. The MagSens system has been adapted from this technology for the purpose of augmenting visual inspection and providing an increased level of safety and cost effectiveness for Rescue Hoist Maintainers.
Magnetic flux leakage cable inspection can identify defects such as broken wires, severe abrasion, necking down, heat damage, corrosion and internal damage in the cable quickly and efficiently by one person in a confined space. Magnetic flux leakage inspection is particularly effective when combined with visual examinations and a thorough understanding of the rescue hoist cable deterioration modes.
The MagSens signal characteristics are indicative of rescue hoist cable defect characteristics. However, the indications or the spike size and shape may be similar for different types of defects. Using the MagSens system, along with a visual examination and knowledge of the history of the cable, provides the users the ability to determine when the cable should be replaced.
The MagSens provides the rescue hoist user organization many benefits as follows:
Detect damage that may occur as a result of the rescue hoist usage in a minimum amount of time.
Eliminate unnecessary replacement of the cable until required.
Provide objective evidence that the cable was in an acceptable condition before the mission.
Track the effects of the helicopter and hoist operation and maintenance techniques upon the rescue hoist cable’s physical condition over time.
The dedicated laptop computer records the results of the inspections. The software records the rescue hoist identification, the date of the test, the results of the test, the amount of cable that was run, and the magnetic signature of the cable for future references.
The MagSens inspection system provides a baseline of the cable when it is installed and then can compare the cable condition during future inspections.
The data files are small so this information can be downloaded to a central location via the internet for users with remote bases