Analysis of the Linear Positioning Accuracy on Z Axis at the Horizontal Machining Centre TMA-AL-550

Abstract:

This paper presents a case study regarding use the laser XL 80 to check the linearity movement of the Z-axis to horizontal machining center, TMA-AL 550. This machining center has been upgraded to the possibility of processing to 3 CNC linear axes and 2 CNC rotary axes (up to 5 CNC simultaneous axes) and also 1 PLC axis (the index table), as well the including of the machine into to the flexible manufacturing cell. This work paper presents the linearity accuracy at machining centre on the Z axis and shows the operating correction parameters by software and the necessity of backlash adjustment between nut and ball screw, by using a performing linear laser for machine tools and research systems laboratory, that was acquired by the project RTT-5 Rotary-Tilting Tables for 5-axis Machining Center, where the authors participated. Compared with conventional methods of checking of table linearity deviations at the machining centers (checking with spirit leveling device, wire collimator, wire auto-collimator and yardstick ruler), the method by laser of unconventional determining brings the following advantages: linear resolution of 0.001 μm, method assisted by computer, in order to obtain the positioning accuracy ± 5 μm the repeatability of 5 μm/m. The measurements fall within the ISO 230-2, ASME B5-52, VDI 3441-DGQ, JIS and GB international standards, and permitting also the memorization of the measured data and the obtaining of the tabulated results, or in graphical form too, using XL 80 soft Laser, by forwarding the information to the computer.

• Periodical: Advanced Materials Research (Volume 837)
• Pages: 179-184
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.837.179
• Online since: November 2013
• Authors: Constantin Bungău, Rareş Pancu, Traian Buidos
• Keywords: CNC Axes, Horizontal Machining Centre, Linear Measurements of Positioning Accuracy, Precision

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