Magnetic rope testing instrument INTROS
General information
Steel rope is subject to deterioration during its service life due to outer and inner corrosion and friction, repetitive bending over sheaves, mechanical damage, overheating, etc. Corrosion and friction reduce the cross-sectional area of the wires of the rope and lead to a loss of metallic area (LMA). Repetitive bending, overheating lead to metal fatigue causes broken wires that degrade integrity of the rope in a localized manner; this is called as local flaw (LF).
The strength of a wire rope reduces throughout its lifetime until the remaining strength is not sufficient to withstand the load applied. Periodic magnetic rope testing is required to remove a rope from service in proper time.
Magnetic rope testing (MRT) works by fully magnetizing a section of rope and then detecting and measuring changes to the magnetic field caused by LMA and LF.
Various standards and codes provide rules and guidance for MRT:
- ASTM E1571-21 - Standard Practice for Electromagnetic Examination of Ferromagnetic Steel Wire Rope;
- ISO 4309:2017 – Cranes – Wire Ropes - Care and Maintenance, Inspection and Discard;
- EN 12927:2019 - Safety requirements for cableway installations designed to carry persons – Ropes;
- IMCA LR 004 - Recommended practice for the examination of steel wire rope through magnetic rope testing (MRT).
The MRT instrument INTROS is the dual-function equipment, i.e. it simultaneously inspects a rope for LF and LMA at high speed. It is suitable for inspection of elevator ropes, crane ropes onshore and offshore, mining ropes, ropes of cableways, stay cables of bridges, guy ropes of flare stacks, communication masts, drilling rigs, overhead power transmission lines, etc. MRT with INTROS can also be carried out at a ropery on newly manufactured ropes prior to them going into service. The results can then be stored and used as a reference for future examinations.
INTROS is suitable for any rope application either on-site or during production run. The INTROS kit comprises the magnetic head and the basic unit interconnected with the cable. For inspection, either rope moves through a magnetic head or magnetic head travels along a rope. Compatibility of basic units and magnetic heads depends on the size of magnetic head.
The special software Wintros, interprets signals from the sensors and stores the data allowing for further analysis including zooming of areas of interest, filtering and comparison with previous tests.
The special release Wintros RTV enables to follow the rope’ traces on-line.
By using the adapter MH-PC interface device, magnetic heads MH6-24M, MH6-26, MH22-45, and MH40-70 can be directly (basic unit is not needed) connected to a computer for recording data and on-line displaying traces on the screen.
