Verktygsmaskiner: allmänt

Ämnesområden: Verktygsmaskiner: allmänt
Kommittébeteckning: SIS/TK 491 (Uppmätning av verktygsmaskiner)
Källa: ISO
Svarsdatum: den 3 maj 2021
Se merSe mindre
 

This International Standard defines procedures for acceptance of metal-cutting machine tools based on the tests of their capability in machining a specified workpiece (i.e. indirect testing). It gives recommendations for test conditions, applicable measurement systems and the requirements for machine tools.

This International Standard is consistent with ISO 22514 (all parts) describing statistical methods for process management and deals with the specific application of those methods to machine tools and machining of a sample batch of test pieces. This International Standard covers neither functional tests, which are generally carried out before testing the accuracy performance, nor the testing of the safety conditions of the machine tool.

Annex A gives additional information related to statistical evaluation, Annexes B and C provide agreement and evaluations forms for short-term capability tests, while Annex D gives an example.

NOTE 1 Direct testing aims to investigate individual machine tool properties, such as geometric or positioning accuracy. Short-term capability evaluation is meant to prove that a machine tool has the capability to fulfil a specific process task. It is, therefore, important to recognise that the short-term capability test is focused only on the manufactured product. This means that direct testing methods are more suited for the determination of error sources on the machine tool and for deriving constructive improvements of a machine tool that is used in a wide production spectrum; a short-term capability test is less suited for detection of error sources of the machine tool. Therefore, it is expected that short-term capability evaluation for the acceptance of metal-cutting machine tools in machining processes be primarily carried out on workpiece-dependent special-purpose machines, e.g. working stations of transfer lines, with a process-determined cycle time of less than 10 min, so that at least 50 workpieces are manufactured in one shift as the statistical uncertainty increases strongly for a smaller number. In principle, short-term capability evaluation can also be performed on universal machine tools, such as machining centres used for large batch production if they meet the above-mentioned statistical requirements.

NOTE 2 The term "short-term capability", which is a widely used term in machine tool industry, corresponds to the term "process performance" specified in ISO 22514-3.

Ämnesområden: Verktygsmaskiner: allmänt
Kommittébeteckning: SIS/TK 491 (Uppmätning av verktygsmaskiner)
Källa: ISO
Svarsdatum: den 3 maj 2021
Se merSe mindre
 

This document specifies test procedures to evaluate the measuring performance of probing systems integrated with a numerically controlled machine tool. Test procedures for touch trigger probing systems and scanning probing systems operating in discrete-point measurement mode are specified in section 7.1. Test procedures are specified for scanning probing systems in 7.2, for bore gauge systems in 7.3, for contacting tool measuring systems in 8.1, and for non-contacting tool measuring systems using the laser light barrier principle in 8.2.

The evaluation of the performance of the machine tool, used as a coordinate measuring machine (CMM), is outside the scope of this document. Such performance evaluation involves traceability issues, is strongly influenced by machine tool geometric accuracy and can, in addition to the machine tool probing system tests specified in this document, be evaluated according to ISO 10360-2 and ISO 10360-5.

Description of test procedures in this document are referred to machining centres. However, tests apply in principle to most NC machine tools.

Ämnesområden: Verktygsmaskiner: allmänt
Kommittébeteckning: SIS/TK 491 (Uppmätning av verktygsmaskiner)
Källa: ISO
Svarsdatum: den 24 maj 2021
Se merSe mindre
 

This document specifies methods for defining machining tests for manufacturing accurate test pieces, and for evaluating the influence of quasi-static geometric errors of linear axes and rotary axes, and the influence of the synchronization error of simultaneously controlled multiple axes. Although quasi-static geometric errors are often major contributors for geometric errors of finished test pieces, other factors, e.g. the dynamic contouring error, can also have significant influence.

This document describes examples of test piece geometry applicable to individual machine tools, possible contributors to machining error, deviations to be measured and measuring instruments. By clarifying possible contributors to machining error in each machining test, this document gives a guidance to machine tool manufacturers or users such that proper machining tests can be chosen to evaluate a machine tool’s machining performance in specified machining applications.

Machining tests to evaluate the geometric accuracy of a single surface are described in Clause 5, and those to evaluate geometric relationship of multiple machining features are described in Clause 6. Clause 7 presents machining tests for other objectives: machining tests for evaluation of short-term capability (subclause 7.2), and machining tests for evaluation of thermal influence (subclause 7.3).