On Efficient Use of Modifying Additives in Restoration of Agricultural Machinery

Statistical analysis of gray iron parts quality of agricultural machinery, according to which the Hc measurements were made, has revealed that the level of this characteristic on the surface has different indicators. They vary from 4,3 to 8,0 A/cm, and on the inside - they reach 5,0 - 9,4 A/cm, which indicates the formation of defects more often in this area. Zones with impaired metal quality (cracks, pores, local stresses, structural deviations of the liquidation phenomena with the formation of non-metallic inclusions) were established by metallographic and micro-X-ray spectral studies, where the Hs indexes increased and reached 7,8-11,3 A/cm. A new approach, assessing a structure formation at the restoration of body parts from gray iron has been developed, based on detection of defects and structure in them by a non-destructive method according to the Hs indices and an optical-mathematical method. Recovery of defects by melting, using a detonation charge from the disposal of ammunition has confirmed the effectiveness of such a modifying impurity when dosing it into a liquid solution of gray iron. Using technology of casting defects welding in the cases of the distribution box at JSC "HTZ" in restoration of 348 pcs makes 746999 UAH per year.