BS ISO 13041-8 pdf download Test conditions for numerically controlled turning machines and turning centres — Part 8: Evaluation of thermal distortions
4Preliminary remarks4.1 Reference to Iso 230-3
To apply this part of lSO 13041, reference shall be made to lSO 230-3,especially for the installation of themachine before testing, description of measuring methods and presentation of the results.
The tests in this part of lSO 13041 may be used either separately or in any combination.
4.3Tests to be performed
When testing a machine, it is not always necessary or possible to carry out all the tests described in this partof ISO 13041. When the tests are required for acceptance purposes, it is up to the user to choose，inagreement with the supplier/manufacturer; those tests relating to the components andor the properties of themachine which are of interest. These tests are to be clearly stated when ordering a machine. Mere referenceto this part of lSO 13041 for the acceptance tests, without specifying the tests to be carried out, and withoutagreement on the relevant expenses,cannot be considered as binding for any contracting party.
5 Environmental Temperature Variation(ETVE) test
ETVE tests are designed to reveal the effects of environmental temperature changes on the machine.Theyshall not be used for machine comparison.
lt is recommended that the supplier/manufacturer should offer guidelines regarding what kind of thermalenvironment should be acceptable for the machine to perform with the specified accuracy. It shall be theresponsibility of the user to provide an acceptable thermal environment for the operation.However, if the userfollows the’ guidelines provided by the machine supplier/manufacturer，the responsibility for machineperformance according to the specification reverts to the machine supplier/manufacturer.
The test method shall be in accordance with those defined in 5.2 of ISO 230-3.The ETVE test should last fora minimum of 4 h; if the readings of the measuring instruments still show any drift, the test should becontinued up to a maximum of 24 h.
NOTE Vertical and slant-bed axes might warm up when under NC “HOLD”command. In such cases,it isrecommended to execute the ETVEtest with all controls “OFF”.This should be stated in the test protocol.
5.3 Measuring instruments
The measuring instruments are as follows: linear displacement probe, temperature sensors, test mandrel anddata acquisition equipment.
5.4Presentation of results
Table 1 provides an example of the format for the presentation of the results;in addition，a graphicalpresentation of results should be provided as specified in 5.3 of lSO 230-3:2001.
5.5 Information to be recorded
a) the name of the manufacturer;
b) the year of construction, if available;
c) the type and serial number;
d) the location of the measurement set-up;
e) the location of temperature sensors;
f) the type of sensors;
g) the design and material of the test mandrel and fixture;
h) the thermal compensation procedure;
i) the any special test procedures;
j) the time and date of test;
k) the machine preparation procedure prior to testing;
l) the control OFF.
6 Thermal distortion caused by rotating spindle
6.1 Number of tests
One test per spindle shall be carried out.
6.2 Test method
The test method shall be in accordance with those defined in 6.2 of ISO 230-3:2001 , however for practical reasons, the test procedure should be the variable speed spectrum.
NOTE A possible example of the speed spectrum cycle could be a percentage of the maximum spindle speed for a set time followed by a spindle stop for another fixed time, (e.g. 70 % maximum spindle speed for 3 min followed by a 1 min stop). This cycle is then repeated for the complete test duration. The exact details of the speed spectrum needs to be discussed between the user and manufacturer/supplier.
The test shall last for 4 h plus 1 h with the spindle stopped.
6.3 Measuring instruments
The measuring instruments are as follows: linear displacement probe, temperature sensors, test mandrel and data acquisition equipment.
6.4 Presentation of results
Table 2 provides an example of the format for the presentation of the results; in addition, a graphical presentation of results should be provided as specified in 6.3 of ISO 230-3:2001 .