the occurrence of chatter vibrations in boring operation has a great influence in improving workpiece dimensional accuracy, surface quality and production efficiency. in this paper instability analysis of machining process is presented by dynamic model of boring machine. this model, which consists of machine tool’s structure, is provided by finite element method and ansys software. the model is...

Machine tool chatter causes machining instability, surface roughness, and tool wear in metal cutting processes. A stability lobe diagram based on regenerative chatter theory is an effective tool to predict and control chatter. Stability diagrams can be applied in machining processes to optimize the maximum depth of cut at the highest available spindle speed, thus improving the material removal ...

Chatter is a complicated problem faced by machine tool operators. Chatter is a self-excited vibration that can occur during machining operations. This is an undesirable phenomenon which limits the productivity of the machine. A lot of techniques have been developed to control the chatter. Stability lobe diagram is an effective tool which helps the operator to select specific spindle speeds duri...

Computation of the stability limit of systems with time delay is essential in many research and industrial applications. Most of the computational methods consider the exact model of the system, and do not take into account the uncertainties. However, the stability charts are highly sensitive to the change of input parameters, such as eigenfrequency and time-delay. Furthermore, the computation ...

INSTRUCTION A more important focus on chatter is the stability boundary analysis that is more practical and realistic in the sense that this analysis shows the chatter boundary region in all available cutting condition and the chatter state for the machinist in field to get the insight easily to avoid the chatter problem. Considering this points, a new method to get the chatter stability bounda...

This paper analyzes the effect of turbulence on the performance of an inverted threelobe pressure dam bearing which is produced by incorporating a pressure dam in the upper lobe and two relief tracks in the lower two lobes of an ordinary inverted threelobe bearing. For analysis purpose different values (0, 1500, 3000, and 6000) of Reynolds number are considered to study the effect of turbulence...

A four-lobe pressure dam bearing which is produced by cutting two pressure dams on the upper two lobes and two relief-tracks on the lower two lobes of an ordinary four-lobe bearing is found to be more stable than a conventional four-lobe bearing. In this paper a four-lobe pressure dam bearing supporting rigid and flexible rotors is analytically investigated to determine its performance when L/D...

This paper presents the effect of experimentally evaluated nonlinearities in a machine joint on the overall machine tool dynamic performance using frequency response functions and stability lobe diagrams. Typical machine joints are very stiff and have weak nonlinearities. The experimental evaluation of the nonlinear joint parameters of a commercial translational guide has been discussed in Dhup...