| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 859289 | Procedia Engineering | 2014 | 8 Pages |
One of the most often produced and controlled elements in the engineering are shafts and holes. In many cases, they are responsible connections, requiring precise control. Measurement of a diameter or roundness deviation for the full profile are well known and commonly used process. However, in many cases it is necessary to measure an element with a incomplete contour. This paper presents results of research on the impact of the incomplete contour length on a diameter and form deviations. We studied the roundness of standard ring with deviation around 0.9 μm and an element of three-lobbing deviation of 37 μm. In both cases, the nominal diameter of the ring was 100 mm.The study was conducted in two stages. The first one was connected with measurement of the roundness deviation for sections 180°, 90°, 45° while the reference was 36°. Measurements were carried out on a CMM and a formtester (FMM). Results show that for the standard ring with decreasing length of the incomplete contour followed by a decrease of roundness. In the case of the three - lobbing ring the section 180° has a form difference value coincides with the value for full profile, while for shorter angular sections those values are greatly diminished.In the second stage, detailed studies that apply measuring sections from 360° to 10° grading in 1° were conducted. Measurements were made for different positions of measuring sections according to the extremes of the outline. The values obtained for the ring with three - lobbing character of form deviation allow to conclude that the diameter remains practically constant for sections up to 210°. Then there is a change in their value which depends on the position of the outline section in relation to extremes. Also the roundness deviation value is constant up to about 210° and then falls and the around 36° reaches value below 1 μm. The studies lead to the conclusion that there is a strong influence of angular measurement section and its position relative to the outlines extremes on achieved the diameter and form deviations.
