ASME B18.2.3.3M:2007 pdf free download.Metric Heavy Hex Screws.
2.1.5 True Position of Head. At maximum material condition, the axis of the hex head shall be located at true position with respect to the axis of the screw (determined over a distance under the head equal to one screw diameter) within a tolerance zone of diameter specified in Table 1.
2.1.6 BearIng Surface. The bearing surface shall be flat and washcr•faced. Diameter of bearing surface shall not exceed the width across flats nor be less than the specified minimum washer lace diameter. For referee purposes, measurement of bearing surface diameter shall be taken at 0.1 mm above the bearing surface. The plane of the bearing surface shall be perpendicular to the axis of the body within the circular runout specified in Table 2. The measurement of bearing face runout shall be made as close to the pcriphui-y of the washer face as possible. while the screw is held in a collet or other gripping device at a distance equal to one screw diameter from the underside of the head.
2.1.7 Undertiead Fillet. The fillet configuration at th junction of the head and shank shall be as shown in Figs. I and 2, and shall have limits as specified in Table 3. The fillet shall be a smooth and continuous curve fairing smoothly into the underhcad bearing surface and the shank within the limits specified. No radius in the fillet contour shall be less than R minimum.
2.2 Body Diameter
The diameter of the body on screws that are not threaded Full length shall be within the limits specified in Tablc 2. For screws threaded full length, the diameter of the unthreaded shank under the head shall not exceed the specified maximum body diameter, nor be less than the minimum body diameter specified in Table I.
2.3 Screw Length
The length of the screw shall be measured parallel to the axis of the screw from the underhead bearing surface to the extreme end of the shank. Tolerances for screw lengths arc given in Table 4,
2.4 Points
fhe end of the screw shall be chamfered from a diameter equal to or slightly less than the thread root diameter to produce a length of chamfer or incomplete thread within the limits for U specified in Table 5. The end of the screw shall be reasonably square with the axis of the screw, and where pointed blanks are used, the slight rim or cup resulting from roll-threading shall be permissible. At the manufacturers option. the end of the screw may have a rounded point of radius. R,, as specified in Table 5.
ASME B18.2.3.3M:2007 pdf free download
