Development of generalized tool life model for constant and variable speed turning

Abstract

In this research, a generalized tool life modelling for considering non-stationary cutting conditions was developed . In particular, for the first time in literature, the model was conceived for predicting the life of the tool when spindle speed variation SSV, one of the most effective techniques for suppressing regenerative chatter vibrations, is used. The proposed formulation takes into account the main cutting parameters and the parameters associated to the SSV. A dedicated experimental campaign of turning tests was executed and the data were used for modelling purposes. The model validation was carried out performing additional tool life tests. According to the analyzed technological scenario, it was found that the generalized formulation can be used for predicting the tool life both at constant spindle machining CSM and adopting SSV with the maximum estimating error of 6%.

Influence of Surface Layer Condition of Al2O3+TiC Ceramic Inserts on Quality of Deposited Coatings and Reliability during Hardened Steel Milling

“…In such a situation, one has to either significantly reduce the cutting conditions, which is not economically feasible, or carry out a forced tool replacement (underestimating the failure criterion) to avoid accidents associated with premature tool failures, i.e., a part of the fully functional tool will be recognized as unusable, which leads to additional production costs. Therefore, the generally accepted practice in high-tech production is the requirement that the dispersion of resistance of 10%-15% and high dispersion of tool resistance values indicate low reliability of the tool and force technologists to underestimate the cutting modes [36][37][38][39][40].…”

Chatter Stability Improvement of a Slender Milling Tool via a Dynamics Variation Mechanism

“…Despite the vast investigations, the SSV methods are not so functional as they impose a large momentum on the heavy rotating parts of the machine tool. Furthermore, SSV methods include some damaging effects on cutting edges which are studied by Albertelli et al [32,33]. In addition to the spindle speed, online variations of other cutting parameters such as cutting angles [34], feed-rate [35], and pitch angle [36][37][38] are used for chatter suppression.…”