Bezpieczeństwo Pracy i Ochrona Środowiska w Górnictwie Number 02/2024

After a long period of use of mine shafts, we have been observing damage to their liners, which can lead to their deteriorated stability, or even to the collapse of the complete shaft. In order to prevent this, ongoing control needs to be exercised by the companies themselves, and periodic inspections need to be performed by material experts. Mining regulations also obligate mining supervision authorities to supervise and assess the technical condition of mine shafts. As of 19 October 2022, mining supervision is the sole responsibility of the President of the State Mining Authority. In accordance with the Geological and Mining Law, they can enforce preventive and verification measures in order to bring any legal activity to its fully legal form. These preventive measures include, among others, evaluation of the correctness of solutions applied, and measurements used for assessing the safety conditions. The company can also be ordered to verify such correctness or perform such measurements. Verification measures include, among others, issuing an order to rectify an irregularity or stop all operations in the complete facility, its part, or with respect to selected equipment.

The service, maintenance and repair of electrical equipment in mining plants are associated with the possibility of accidents occurrence (electric shock or electric arc burn). Only small percentage of them involve injuries to the eyeballs, but they have a direct impact on the functioning of the injured in their lives. Analysis of such accidents shows that their common cause was the lack of proper organization and supervision of the work performed. To Mine Restructuring Company S.A. there are passed on mines for liquidation or transforming into a pumping stations. Each of them is characterized by different electrical devices, what needs individual approach to operation and servicing of the devices. So, the company's services are planning to implement solutions which improve the safety of electrician. They include creation of central records of: electrical insulating equipment, directions of servicing, maintenance as well as inspections and tests of electrical devices. Moreover, they include a single programme of trainings for electric services. These activities should lead to: reduction of hazards and potentially dangerous events, improvement of rationality management of available human resources as well as to minimize risks related for example to mistakes during servicing electrical devices or unorganized work.

The article presents selected issues of testing of multilayer ropes with polymer filling after them discarding. The main reason for the users' decision to put the ropes down was the severe corrosion of the pitting of the wires in the strands of the outer layer in the result of the ropes use in a highly corrosive environment. The results and conclusions contained in the article arise from several years of experience gained during appraisal tests of such a ropes in mining shaft hoists, and then tests of their selected sections in the laboratory of the AUTORYTET Ltd in Polkowice. The laboratory examinations included visual and magnetic tests on a measuring stand, followed by visual and strength tests of selected samples of rope in the unstranded state. The tests of the polymer-filled multilayer ropes showed the advantages of this construction. The vast majority of its wear symptoms (i.e. pitting corrosion) could be seen in the outer layer of strands, which accounts for 76% of the rope cross-sectional area. So, it can be stated that the polymer filling in the entire rope cross-section effectively protects the interior of the rope against the penetration of aggressive shaft water as well as stabilizes and separates the individual layers of strands in the rope. Detection and evaluation of corrosion progress was possible during periodic testing by magnetic and visual examinations.