ASME B18.16M pdf download

ASME B18.16M pdf download.Prevailing-Torque Type Steel Metric Hex Nuts and Hex Flange Nuts.
7 WIDTH ACROSS FLATS
11w width across flats shall be the distance, measured perpendicular to the axis of the nut, between two opposite wrenching flats. The maximum width across flats may be exceeded by 0.05 mm to allow fai nut deformation caused b’ introduction of the prevailing-torque feature. The width across flats and width across corners may be less than the specified minimum in the deformed portion of the nut containing the prevailing-torque featore.
At maximum material condition the axis of the hex.igun shall be located at true position with respect to the axis of the thread pitch diameter within a tolerance lone having a diameter equivalent to 4% of the maximum width across flats.
B THICKNESS
The nut thickness shall be the overall distance, measured parallel to the axis of the nut, from the top of the nut to the bearing surface of hex nuts, and to the plane of the bearing circle diameter of hex flange nuts. Raised identification markings, if present. shall be excluded.
9 WRENCHING HEIGHT
Thc wrenching height is the distance, measured at a corner of the hex, from the bearing surface of hex nuts, and from the junction of the hex portion with the flange of hex flange nuts to the last plane of full formed hex. i.e., the plane perpendicular to the nut axis that Is closest to the top of the nut and at which the width across corners is within its specified limits. Wrenching height for hex nuts is dimension M1 in Table I, and is subject to measurement. Wrenching height for hex flange nuts is dimension T4 in Table 2 and is controlled by the gaging requirement specified in para. 10.
10 GAGING OF HEX PORTION OF HEX FLANGE NUTS
The nut shall be gaged using two plain ring gages. A and B, to demonstrate the coincidental acceptability of hex height, wrenching height, and width across corners, (See figure above Table 2.) Gage A shall be placed over the hex and shall seat on the flange. Gage B shall be placed on the top of the nut normal to the nut axis. The two gages shall not be in contact.
12 BEARING SURFACE
I-ks nuts shall be corner chamfered and have a flat beanng surface. The diameter of the bearing surface shall net exceed the width across flats nor be less than the bearing face diameter specified in Table 1.The bearing surface shall be Flat and perpendicular to the axis of the thread within the total runout limit specified in Table I.
The beanng surface of hex flange nuts shall be flat to concave to a maximum of 1.5 deg from the plane formed by the beanng dnle diameter, The beanng circle shall be perpendicular to the axis of the thread pitch diameter within the circular runout, full indicator movement (FIM). specified in Table 2. when measured at diameter D.
13 COUNTERSINK
The ta1wd hole shall be countersunk on the bearing face, and may be countersunk on the top face. ll,e countersink included reference angle shall be 90 deg to 120 deg. The maximum countersink diameter shall be
1.15 times the nominal thread dianwter (major diameter) for nuts M4 and smaller, the nominal thread diam• eter plus 0.75 mm br MS through M nuts, and lAJtt times the nominal thread diameter for MlO and larger nuts. The minimum countersink diameter shall be the nominal thread diameter.