The continuous control of the abrasive mass flow rate and feed rate as a new opportunity in the AWJ precision machining

摘要

The possibility to simultaneously control the abrasive mass flow rate and the feed rate in the AWJ machining has been studied in the frame of the present work: making use of a device able to continuously control the abrasive mass flow rate during the cutting operations, the advantages obtainable combining the control of this parameter with the control of the feed rate have been pointed out. When the feed rate has to be reduced, for example close to the changes of direction, some geometrical characteristics of the kerf may change, as the kerf width and taper; in this case it is possible to act on the abrasive mass flow rate reducing it in order to compensate, under the taper point of view, the effect of the feed rate decrease. At the same time the tolerance of the obtained shape can be maintained by means of a cutting path correction. Also the typical geometrical problems on the corners due to the jet deflection (1) could be reduced by the continuous control of the abrasive mass flow rate. The validity of this kind of approach is particularly evidenced when the opportunity provided by the current CNCs cannot meet the quality requirements: the continuous control of the abrasive mass flow rate could operate widening the field of application of the AWJ precision machaning. In order to point out the mentioned advantages coming from the continuous control of the abrasive mass flow rate and the feed rate in the AWJ cutting operations, an opportunely designed experimental campaign has been carried out.