USING HARD-METAL DEPOSITS IN SUGAR BEET HARVESTERS

Mobile energetic means used for sugar beet harvesting can be classified as machines with a high abrasive wear of their functional parts. This is caused mostly by direct contact of the functional mechanisms with abrasive soil particles. Taking into consideration the amount of material which has to be processed during one season, it is obvious that the financial costs of replacement and renovation of the functional parts are considerable. This experiment focuses on using weld deposit materials in order to increase the resistance of transport mechanisms to abrasive wear. Martensitic and ledeburitic types of materials were tested, both of which were deposited on base steel samples using the MMA method; it is a method that can be applied in standard agricultural service. The material used directly for worm-conveyors served as a reference standard. The abrasion resistance of the tested materials was observed in the Bond's device. Ceramic granulation product with fractions of 5 and 2 mm served as the abrasive medium. Based on the performed tests, it can be concluded that carbide weld deposits demonstrate higher abrasion resistance. A potential risk can be seen in fragmentation of weld bead as a result of pressure stress in a heat-affected place. Hard metal weld deposits however, have an irreplaceable place in machine parts used under high abrasive stress conditions.