The paper presents the implementation of the method of own residual magnetic field to identify damages occurring in a steel rope. A special measuring head with 4 residual magnetic field sensors, spaced evenly every 90 degrees, was used. The measuring head was also equipped with a path or a time sensor. The measurement consists in recording normal and tangential components of the residual magnetic field and their gradients. This method has a number of advantages with regard to classic magnetic methods. It does not require special magnetisation of the rope or its special preparation for testing. Validation of the obtained test results of this rope was conducted by the classic MTR method and a very good compliance in the detection of damage was demonstrated. It was found that the strong magnetisation used in the MTR method does not affect the detection of damage to the rope using the residual magnetic field method.
The brake linkage of a hoisting machine is a very important component determining the safety of
the hoisting machine’s entire braking system. It is subject to weekly inspections. However, an efficiency
test of brake performance is carried out every 6 months. Once every 3 years, a test must be carried out by
an appraiser who pays particular attention to the executive and control components of the brakes as well
as the strain - brake system and brake release components. The legal provisions regulating the testing
of braking system linkages are not precise. So far, the control has been based on random measurement
of strains using electrical resistance strain gauges stuck to the surface of the linkage. A new method
for measuring the strains of the linkage has been proposed in the work. It is based on fibre optic strain
sensors with Fibre Bragg Gratings (FBG). They are mounted using specially designed and tested holders
for mounting on the brake linkage. They provide quick assembly and the measurement of strain in the
direction parallel to the axis of the linkage. The structure of the holder also allows for the measurement
in 4 positions turned every 90 relative to one another. Such a measurement enables a comprehensive
analysis of strains and stresses in the brake linkage. In the work, it was shown that there is a complex
state of strain and stress in the brake linkage. The previous procedures for linkage testing are inadequate
in relation to this condition. An experimental and numerical method was proposed to assess the state
of linkage stress. It should constitute the basis for the decision of the appraiser to allow the linkage for
further use. The method proposed in the work also allows for continuous measurements of linkage strains
as well as dynamic braking tests.