Tham khảo tài liệu 'cutting tool back matter part 3', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Appendix 569 o Appendix 10a. Diagram illustrating how profile shape varies as the horizontal magnification is reduced I Surface profile magnified x5 000 equally in all directions II Profile with a Vv Vh ratio of 5 1 III Profile graph recorded with a Vv Vh ratio of 50 1. Courtesy of Taylor Hobson 570 Appendix ZịjiS 10-point height Although the parameter has now been deleted from the latest ISO standard ISO 4287 1997 it has been included in this discussion as there are still many engineering drawings in existence that utilise this surface texture descriptor. The Z J1S parameter averaged the peak-to-valley values which had the effect of reducing the influence of either a spurious irregularity or a scratch. As its name suggested it was derived from 10 points within the sampling length . being a German-based standard the letter z was derived from the German Zehn Punkt Hohe which equates to 10-point height and is the mean distance between the five highest and lowest peaks and valleys respectively measured perpendicularly to a base line. Zạ Zp2 Zp3 Zp4 Zps SAMPLING CUT-OFF LENGTH JIS Zpi Zp2 Zp3 Zp4 zp5 ZVj 4- Zv2 4- Zv3 4- Zv4 4- Zv5 5 The five peaks and valleys can be located anywhere across the sampling length unlike R DIN allowing it to be utilised for short surface lengths whereas the alternative Ấ DINJ would be inappropriate because significant peaKS or valleys per cutoff length are not present. o Appendix 10b. Rz 10-point amplitude parameter - its derivation. Courtesy of Taylor Hobson Appendix 571 a High spot count HSC Selectable of slice level 2 Count Sampling cut-off length NB THE SELECTABLE BAND IS AT THE DISCRETION OF THE INSPECTOR - FOR BOTH HSƠ AND RSm o Appendix 10c. HSC High Spot Count and the Rsm mean peak spacing - spacing parameters. Courtesy of Taylor Hobson
