tailieunhanh - Dimensioning and Tolerancing Part 12

Tham khảo tài liệu 'dimensioning and tolerancing part 12', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | ASME DIMENSIONING AND ĨOLERANCING FIG. 6-13 SPECIFYING DIFFERENT PROFILE TOLERANCES ON SEGMENTS OF A PROFILE THIS ON THE DRAWING plane A The surface between points D and E must lie between two profile boundaries apart perpendicular to datum plane A equally disposed about the true profile and positioned with respect to datum planes B and c. FIG. 6-14 SPECIFYING PROFILE OF A SURFACE BETWEEN POINTS 166 DIMENSIONING AND TOLERANCING ASME THIS ON THE DRAWING MEANS THIS Datum plane A The surfaces all around must lie between two profile boundaries apart one coincident with and the other outside the true profile and both perpendicular to datum plane A. The tolerance zone extends to the intersection of the boundary lines. FIG. 6-15 SPECIFYING PROFILE OF A SURFACE FOR SHARP CORNERS files taken at various cross sections through the part. These two cases are provided for as follows. a Profile of a Surface. The tolerance zone established by the profile of a surface tolerance is three-dimensional extending along the length and width or circumference of the considered feature or features. This may be applied to parts having a constant cross section as in Fig. 6-12 to parts having a surface of revolution or to parts such as castings defined by profile tolerances applying ALL OVER as indicated below the feature control frame. b Profile of a Line. The tolerance zone established by the profile of a line tolerance is two-dimensional extending along the length of the considered feature. This applies to the profiles of parts having a varying cross section such as the tapered wing of an aircraft or to random cross sections of parts as in Fig. 6-18 where it is not desừed to conưol the entire surface of the feature as a single entity. Explanation of Profile Tolerance. The tolerance value represents the distance between two boundaries equally or unequally disposed about the true profile or entirely disposed on one side of the true profile. .