Proceedings of SerbiaTrib '13

Serbian TribologySocietySERBIATRIB ‘1313 th International Conference onTribologyKragujevac, Serbia, 15 – 17 May 2013Faculty of Engineeringin KragujevacTRIBOLOGICAL ASPECTS OF THE PROCESS OF WINDINGTHE STEEL ROPE AROUND THE WINCH DRUMMiloš Matejić 1 , Mirko Blagojević 1 , Vesna Marjanović 1 , Rodoljub Vujanac 1 , Boban Simić 21 Faculty of Engineering, University of Kragujevac, Serbia,mmatejic@kg.ac.rs, mirkob@kg.ac.rs, vmarjanovic@kg.ac.rs, vujanac@kg.ac.rs2 D.O.O RAPP Zastava, Serbia, bsi@rappzastava.comAbstract: Proper winding of the steel rope around the winch drum is great importance, mostly for:prolonging the service life of the rope, reduction of deformations of the body and the sides of the drum if thewinding of the rope is multilayered, increasing of the safety factors, easier unwinding of the rope whilelowering the load, even running of the drive unit, etc. The focus of this paper is on the analysis of the frictionwhich occurs in the process of winding and unwinding the rope around the winch drum. Friction force is inits highest intensity when the rope passes from one layer to another, if the winding of the rope ismultilayered. As the result of the research, certain mechanisms of winding of the rope from the aspects of thefriction force were obtained, and the affect of the forces on the sides of the drum were analyzedKeywords: winch, drum, rope, friction, friction force.1. INTRODUCTIONModern technological achievements haveenabled a great progress in the ship equipmentindustry. Ship winches, as one of the mostimportant parts of the equipment, are highlydeveloped. Their dimensions, compared to the forcethey use, have been reduced and the degree ofefficiency has increased with the use of variouskinds of compact mechanical gear and drive. Thecapacities for winding of the ropes have beenincreased for any kind of use on the vessels, fromthe oceanographic researches on the bottom of theocean, to catching of the special kinds of fish.A lot of research into vessel winches have beendone: increasing of the degree of efficiency,reduction of dimensions, reduction of the mass ofwinches, improvement of the drive unit regardingthe compactness and the power they use,improvement of the drum for rope-winding as thebasic element of a winch, of the rope-windingsystem, development and analysis of the varioustypes of ropes for various uses, etc.Great attention is paid to examination anddevelopment of the ropes used for winches. Steelropes are mostly used for vessel winches, while thesynthetic ones are rarely used. Different types ofcables are used for winches for oceanographicresearches rather than ropes because of thetransmission of information from the researchdevices from the bottom of the ocean to the vessel.When it comes to the development of the new typesof ropes, great attention is paid both to the outertensile and twisting forces affecting the rope, andthe inner friction forces that occur between thewires of the rope, [1], [2], [3]. When examining theexisting types of ropes, it is very important toexamine the inner friction in the ropes, as well asthe failure mechanism of the ropes, [4], [5]. In thecase where the steel rope cannot be installed on awinch because of its large mass, synthetic ropes areused. Synthetic ropes are still not widely usedbecause they are still in the development andimprovement stages, [6]. Synthetic ropes can bemade with the molten core for the improvement ofits mechanical characteristics.Reduction of the dimensions and the increase inthe degree of efficiency of a winch is mostlyachieved by installing the compact mechanicalgear, gearboxes. Single-stage gearboxes with two,three or more drives are often used for increasingthe compactness of the vessel winch constructions,[7]. In addition, the use of planetary gearboxes is234 13 th International Conference on Tribology – Serbiatrib’13