Welding and Build-Up Technologies at Dredge Scooping Pin Manufacture and Renovation

The purpose of the development is to determine the possibility to manufacture welded dredge scooping pins providing for the structure operational capacity as well as to find out how to repair and reinforce such pins to extend their service life. The pins are used to connect dredge scoops into a scoop chain at gold and diamond dredges. The quality of pins significantly influences the stable operation of a dredge scoop mechanism, its early wear-out or destruction can lead to the increase of the load imposed on the mechanism drive and even to a self-induced scoop chain descending which is a crucial breakdown and can cause significant damages. At the moment, the key method to manufacture the pin dies is hot stamping which is very expensive and requires cooperation with the companies possessing high-power stamping facilities. Methods: The authors propose using a welded pin design instead of the one-piece forged one as well as the technology to renovate the worn-out pins. The authors conducted the research on the connection and build-up metal structure and their mechanical properties. Materials: The authors managed to choose a doping pattern and determine the welding and build-up metal chemical content. The research results ascertained the possibility to use the welded pin design and the development of the welding and build-up technology at prefabrication as well as the technology for remanufacturing of worn-out pins at gold-mining companies. Conclusion: The production of the developed materials and the welded pin manufacturing technology were adopted and implemented by the Irkutsk Heavy Machinery Plant (IZTM), while a number of gold-mining companies adopted the technology allowing for the worn-out pin renovation.