This part of ISO 10791 specifies, with reference to ISO 230-1, the geometric tests for machining centres (or numerically controlled milling machines, boring machines, etc., where applicable) with vertical spindle (that is vertical Z-axis).

This part of ISO 10791 applies to machining centres having basically three numerically controlled axes, that is three linear axes (X, Y and Z) of up to 2 000 mm length, but also refers to supplementary motions, such as rotary axes (A′ , B′ and C′), those of rams, quill, or universal heads. Motions other than those mentioned are considered as special features and the relevant tests are not included in this part of ISO 10791.

This part of ISO 10791 describes geometric tests for optional horizontal spindles as well as for two possible types of universal heads in the following annexes:

• annex A: optional horizontal spindles (tests AG1 to AG6);
• annex B: rotary heads, with one numerically controlled rotary axis (tests BG1 and BG2);
• annex C: swivel heads, with two numerically controlled rotary axes perpendicular to each other (tests CG1 to CG7).

This part of ISO 10791 deals only with the verification of the accuracy of the machine. It does not apply to the testing of the machine operation, which should be checked separately. Some tests concerning the performance of the machine operating under no-load or finishing conditions are included in other parts of ISO 10791.