CLAMPING DEVICES WITH SPLIT SLEEVES. ACCURACY OF BLANKS INSTALLATION AND MACHINING

Abstract

A special place in the known technological system “MDTP” (machine, device, tool, part) is taken by clamping devices since they are intended for positioning of the blank (part) subject to machining in space to prevent its displacement under the action of cutting forces. The devices significantly influence the accuracy of the clamped blank machining. The ratio of inaccuracies caused by the devices may prevail in the total balance of inaccuracies. This may take place during machining of such types of blanks as rings, bushings and cups, especially those with thin walls. The mentioned blanks have a great number of structural configurations, they vary in installation bases, rigidity, accuracy requirements and batch quantity, etc. All this has led to a great number of devices used to install such blanks as rings, bushings and cups. These devices were selected as objects of study. The review thereof has shown two contradictory tendencies: increase in accuracy of machining of blanks clamped in the devices; expansion o the devices’ processing possibilities, in the first instance expansion of the diameter range of blanks which can be installed in a single device. On the basis of the study performed it was determined that mandrels with split sleeves are most promising since they are highly accurate and have a wide range, but there is some room for improvement of these characteristics. The article describes accuracy of blanks’ installation and machining in mandrels with split sleeves and contains recommendations on rational use of such mandrels.