This document specifies requirements and provides calculations for the permissible static and dynamic residual unbalances of rotating single tools and tool systems. It is based on the guideline that unbalance related centrifugal forces induced by the rotational speed do not harm the spindle bearings, as well as prevent unbalance related impairments of machining processes, tool life and work piece quality.
NOTE1 Tools and tool systems covered by this document are, for example, those with hollow taper interfaces (HSK) according to ISO12164‑1 and ISO12164‑2 , modular taper interface with ball track system according to the ISO26622series polygonal taper interface according to the ISO26623series , taper7/24 according to ISO7388‑1 , ISO7388‑2 , ISO9270‑1 and ISO9270‑2 related to their individual operating speed.
Modular tool systems are another important and complex issue of this document. Calculations and process descriptions for balancing these components and the assembled tool systems are included.
This document is putting an important focus on the possible clamping dislocations of tool shanks and their effects on the balancing procedure. These dislocations can occur between a tool or a tool system and the machine tool spindle (e.g. with every tool change), as well as within a modular tool system during its assembly.
NOTE2 Unfavourable process or system conditions (e.g. partial resonances of the machine structure generated by particular rotational speeds) or design and machine-related technical conditions (e.g. the projecting length of the axes, narrow space conditions, vibration susceptible devices, clamping devices and tool design) may lead to increased vibration loads and balancing requirements. This is dependent on the individual interaction of the machine and the tool spindle system and cannot be covered by a standard. A deviation from the recommended limit values of this document can be required in individual cases.
NOTE3 Wear of the shank interfaces may lead to possible variations of the clamping situation and thus to worse run-out and balancing conditions. These errors cannot be specifically addressed in a standard.