ISO 17543-1-2020 pdf download.Machine tools – Test conditions for universal spindle heads – Part 1: Accessory heads for machines with horizontal spindle (horizontal Z-axis).
Tests shown in this document check only the resulting position of the spindle axis in the possible orientations of the head, and they are intended to be used for acceptance purposes.
Annexes A and contain additional tests to check all the geometric features (planes and axes) which contribute to the resulting position of the spindle, by-passing the positioning deviations of the two rotary axes; these tests provide a technical means for a deeper investigation and a diagnostic analysis on the accuracy of the head components and of their assembly, both on a new head and during the working life of a head in use.
Annex C contains tests for checking the accuracy of axes of rotation.
4.5 Measuring instruments
Measuring instruments indicated in the tests described in Clauses 5. , 7 and in Annexes A to C are only examples. Other instruments capable of measuring the same quantities and having the same, or a smaller, measurement uncertainty may be used. Reference shall be made to ISO 230-1:2012, Clause 5, which indicates the relationship between measurement uncertainties and the tolerances.
When a dial gauge is referred to, it can mean not only dial test indicators (DTIs), but any type of linear displacement sensor such as analogue or digital dial gauges, linear variable differential transformers (LVDTs), linear scale displacement gauges or noncontacting sensors, when applicable to the test concerned (see ISO 230-1:2012, Clause 4).
Similarly, when a straightedge is referred to, it can mean any type of straightness reference artefact, such as a granite, ceramic, steel, cast iron straightedge, one arm of a square, one generating line on a cylindrical square, any straight path on a reference cube or a special, dedicated artefact manufactured to fit in the T-slots or other references.
In the same way, when a square is mentioned, it can mean any type of squareness reference artefact, such as a granite or ceramic or steel or cast iron square, a cylindrical square, a reference cube or, again, a special, dedicated artefact.
Valuable information for measuring instruments is available in ISO/TR 230-11.
4.6 Software compensation
4.6.1 Head offset compensation
The NC control can compensate offsets between axes, which can result from either of the following:
— the head design: e.g. in two-spindle square heads with rigid body the cross-spindle can lie in a different plane from the longitudinal spindle (see Eigure2) or in swivelling heads with the A-axis perpendicular to the C-axis the spindle axis S can swivel in a plane not containing the C-axis (see Figure 5)
— the natural small inaccuracies in machining and assembling the head components (see Figure 3 and Figure 4).
In this second case, the concerned tests may be carried out with and/or without applying the offset compensation, according to the test purpose, and this should be specified in the test report for every concerned test.
This double option of test allows assessing both the original mechanical accuracy and the offset compensation accuracy. The intended use of the machine tool shall be considered.ISO 17543-1 pdf download.