Papers by Keyword: WC-Co Cemented Carbide Ball

Abstract: In order to get high precision balls used in oil exactor, Eccentric dual-rotating (EDR) V-groove lapping mode and Rotated dual-plates (RDP) lapping mode are applied for the batch processing of WC-Co cemented carbide balls of Φ35mm. After comparing two innovated modes, firstly EDR V-groove lapping mode is used in rough lapping stage for high efficiency, and then semi-finishing lapping stage, finishing lapping stage and polishing stage are carried out by RDP lapping mode. Through changing the processing parameters legitimately, including abrasive grain, adjustable rotating velocity and load, the rational course and parameters are defined, and WC-Co cemented carbide balls of Φ35mm satisfy the end products’ demand which means the sphericity is less than 1μm and the roughness of surface (Ra) is better than 50nm, so these balls can be applied in one-way hydraulic value used in oil exactor.

Abstract: To study the lapping process and sphere-shaping mechanism of WC-Co cemented carbide ball under eccentric dual-rotating (EDR) V-groove lapping mode, the research center designs EDR V-groove lapping machine. This paper analyses sphericity of WC-Co cemented carbide balls after the lapping. During the lapping process, the diameter variation is measured every one hour. The diameter of ball is usually reduced 0.05mm every hour, which is more than the dual rotating plates(DRP) lapping mode, and the experiment is totally done 9 hours, the error of sphericity can be controlled around 0.005mm in the last, so the EDR V-groove lapping mode is more suitable for lapping of the WC-Co cemented carbide ball in roughness and semi-finishing process. In order to compare the material removal rate between DRP lapping mode and EDR V-groove lapping mode, the balls are also lapped under DRP lapping mode.

Abstract: In this paper, the batch processing of Φ35mm WC-Co cemented carbide balls used in one-way value is studied by rotated dual-plates (RDP) lapping machine. On the basis of this innovated equipment, the processing parameters, including abrasive grain, rotating velocity and load, are changed legitimately in experiment. The experimental results show that the abrasive grain is used from big to small, while the rotating velocity and load are gradually reduced in order to improve the uniformity of lapping trace distribution on the ball surface in batch processing. Finally the rational course and parameters are defined, these WC-Co cemented carbide balls satisfy the products’ final demand which means the sphericity error (Rnd) is less than 1μm and the roughness of surface (Ra) is better than 50nm. Because of the feasibility, the precision of final WC-Co cemented carbide balls improves and can be applied in one-way value used in oil exactor.