ASME B18.2.3.2-2005 pdf free download.Metric Formed Hex Screws
.6 Thread Length
The length of thread on screws shall be controlled by the maximum grip length, L g , and the minimum body length, L s , as set forth in this section.
6.6.1 Grip Gaging Length, L g . The grip gaging length, L g , is the distance, measured parallel to the axis of the screw, from the underhead bearing surface to the face of a noncounterbored or noncountersunk standard GO thread ring gage assembled by hand as far as the thread will permit. For standard diameter-length com- binations of screws that are not threaded full length, the values for L g max. are specified in Table 5. For diameter- length combinations not listed in Table 5, the maximum grip gaging length, as calculated and rounded to one decimal place, shall be equal to the nominal screw length, L, minus the reference nominal thread length, B,as specified in Table 8 ( L g max. = L – B ). L g max. shall be used as a criterion for inspection. For screws of nom- inal lengths, L , that are equal to or shorter than the lengths specified in Table 8 for screws threaded full length, L g max. = L u max. as specified in Table 8.
6.6.2 Body Length, L s . Body length, L s , is the dis- tance, measured parallel to the axis of the screw, from the underhead bearing surface to the last scratch of thread or top of the extrusion angle, whichever is clos- est to the head. For standard diameterlength combina- tions of screws that are not threaded full length, the values of L s min. are specified in Table 5. For diameterlength combinations not listed in Table 5, the minimum body length, as calculated and rounded to one decimal place, shall be equal to the maximum grip gaging length (1) R e approx. equals 1 .4 times thread major diameter and agrees with ISO 4753 . (2) U max. equals two times the thread pitch.
6.6 Thread Length The length of thread on screws shall be controlled by the maximum grip length, L g , and the minimum body length, L s , as set forth in this section.6.6.1 Grip Gaging Length, L g .
The grip gaging length, L g , is the distance, measured parallel to the axis of the screw, from the underhead bearing surface to the face of a noncounterbored or noncountersunk standard GO thread ring gage assembled by hand as far as the thread will permit. For standard diameter-length combinations of screws that are not threaded full length, the values for L g max. are specified in Table 5. For diameterlength combinations not listed in Table 5, the maximum grip gaging length, as calculated and rounded to one decimal place, shall be equal to the nominal screw length, L, minus the reference nominal thread length, B, as computed, minus the transition thread length as specified in Table 8 ( L s min. = L g max. – X ref.). L s min. shall be used as a criterion for inspection. For screws that are threaded full length, the distance from the underhead bearing surface to the face of a noncounterbored or noncountersunk standard GO thread ring gage assembled by hand as far as the thread will permit shall not exceed the length, L u , as specified in Table 8. For screws threaded full length, the last scratch of thread must not be within the maximum fillet length, F 1 max., as specified in Table 3: L u min. = F 1 max.
6.6.3 Thread Length, B. Thread length, B, a reference dimension, as specified in Table 8, is intended for calculation purposes only, and is the distance, measured parallel to the axis of the screw, from the extreme end of the screw to the last complete (full form) thread.ASME B18.2.3.2 pdf download.ASME B18.2.3.2-2005 pdf free download
