tailieunhanh - Dimensioning and Tolerancing Part 4

Tham khảo tài liệu 'dimensioning and tolerancing part 4', 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 TOLERANCING FIG. 3-5 PLACEMENT OF DATUM FEATURE SYMBOL IN CONJUNCTION WITH A FEATURE CONTROL FRAME Statistical Tolerancing Symbol. The symbolic means of indicating that a tolerance is based on statistical tolerancing is shown in Fig. 3-8. If the tolerance is a statistical geometric tolerance the symbol is placed in the feature control frame following the stated tolerance and any modifier. See Fig. 3-9. If the tolerance is a statistical size tolerance the symbol is placed adjacent to the size dimension. See Figs. 2-20 and 3-10. Between Symbol. The symbolic means of indicating that a tolerance applies to a limited segment of a surface between designated extremities is shown in Figs. 3-8 3-11 6-13 and 6-14. In Fig. 3-11 for example the tolerance applies only between point G and point H. Counterbore or Spotface Symbol. The symbolic means of indicating a counterbore or a spotface is shown in Fig. 3-12. The symbol precedes with no space the dimension of the counterbore or spotface. Countersink Symbol. The symbolic means of indicating a countersink is shown in Fig. 3-13. The symbol precedes with no space the dimensions of the countersink. Depth Symbol. The symbolic means of indicating that a dimension applies to the depth of a feature is to precede that dimension with the depth symbol as shown in Fig. 3-14. The symbol and the value are not separated by a space. 44 DIMENSIONING AND TOLERANCING ASME TERM SYMBOL SEE AT MAXIMUM MATERIAL CONDITION AT LEAST MATERIAL CONDITION PROJECTED TOLERANCE ZONE FREE STATE TANGENT PLANE DIAMETER 0 SPHERICAL DIAMETER S0 RADIUS R SPHERICAL RADIUS SR CONTROLLED RADIUS CR REFERENCE ARC LENGTH STATISTICAL TOLERANCE st BETWEEN FIG. 3-8 MODIFYING SYMBOLS FIG. 3-9 SYMBOL INDICATING THE SPECIFIED TOLERANCE IS A STATISTICAL GEOMETRIC TOLERANCE FIG. 3-12 COUNTERBORE OR SPOTFACE SYMBOL