BS ISO 3875:2020 pdf download.Machine tools — Test conditions for external cylindrical centreless grinding machines — Testing of the accuracy.
5.2 Reference to Iso 230-1 and ISO 230-2
To apply this document, reference shall he made to Iso 230-1 and ISO 230-2, especially for the installation of the machine before testing, the warming up of spindles and other moving components, description of measuring methods and recommended measurement uncertainty of testing equipment.
Where the test concerned is in compliance with the specifications of ISO 230-1 and ISO 230-2, a
reference to the corresponding subclause in ISO 230-1 and 150 230-2 is shown before the instructions
in the ‘Observations” block of the tests described in Clauses.6 to 8.
5.3 Machine levelling
Before conducting tests on a machine, the machine should be levelled according to the recommendations of the supplier/manufacturer (see ISO 230-1:2012, 6.1.1).
5.4 Testing sequence
The sequence in which the tests are presented in this document does not defines the practical order of testing. In order to make the mounting of instruments or gauging easier, tests may be performed in any order.
5.5 Tests to be performed
When testing a machine, it is not always necessary or possible to carry out all the tests described in this document. When the tests are required for acceptance purposes, it is up to the user to choose, in agreement with the supplier/manufacturer, those tests relating to the components and/or the properties of the machine which are of interest. These tests are to be clearly stated when ordering a machine. A simple reference to this document for the acceptance tests, without specifying the tests to be carried out, and without agreement on the relevant expenses, cannot be considered as binding for any contracting party.
5.6 Measuring instruments
Measuring instruments indicated in the tests described in Clauses 6 to are examples only. 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 (DTI) hut any type of linear
displacement sensor such as analogue or digital dial gauges, linear variable differential transformer
(LVDTsJ, linear scale displacement gauges, or non-contact sensors, when applicable to the test concerned
(see ISO 230-1:20 12, Clause 4).
Similarly, when a straightedge is referred to, it can mean any type of straightness reference artefact, I such as a granite or ceramic or steel or 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.
Valuable information for measuring instruments are available in ISO/TR 230-11.
5.7 Machining tests
Machining tests shall be made with finishing cuts only. Roughing cuts shall be avoided since they are liable to generate appreciable cutting forces.BS ISO 3875 pdf download.