ASME B18.16M:2004 pdf download

ASME B18.16M:2004 pdf download.Prevailing- Torque Type Steel Metric Hex Nuts and Hex Flange Nuts
1 SCOPE
This Standard covers the complete general, dimen- sional, mechanical, and performance data for metric prevailing-torque hex nuts and hex flange nuts of prop- erty classes 5, 9, and 10 as defined in ASTM A563M. The inclusion of dimensional data in this Standard is not intended to imply that all of the nut sizes in con- junction with the various options described herein are stock items. Consumers should consult with suppliers concerning lists of stock production prevailing-torque hex and hex flange nuts.
2 COMPARISON WITH ISO STANDARDS
2.1 Coordination With ISO Standards Hex and hex flange nuts as covered in this Standard have been coordinated to the extent possible with ISO 2320, ISO 7040, ISO 7041, ISO 7042, ISO 7043, ISO 7044, ISO 7719, and ISO 7720. The dimensional differences are few, except those of the M10 size. None affect the func- tional interchangeability of nuts manufactured to the re- quirements of either. The clamp torque values in Table 4 of this Standard are significantly different compared to the applied torques in ISO 2320 Annex C. ISO 2320 does not make any coating distinctions. 2.2 Letter Symbols Letter symbols designating dimensional characteris- tics are in accord with those used in ISO standards, ex- cept that capitals have been used instead of lower case letters used in ISO standards. 2.3 ISO Width Across Flats M10 hex and hex flange nuts with 15 mm width across flats are currently being produced and used in the U.S. and many other countries. This width across flats is not ISO standard for hex nuts, but is ISO standard for hex flange nuts. The ISO standard for M10 hex nuts speci- fies 16 mm width across flats. Unless M10 hex nuts with 15 mm width across flats are specifically ordered, M10 hex nuts with 16 mm width across flats shall be fur- nished.
5 DIMENSIONS
Unless otherwise stated, all dimensions in this Stan- dard are in millimeters (mm), and apply before any plat- ing or coating. When a plating or coating is specified, the finished product dimensions shall be as agreed upon between supplier and purchaser. Symbols specifying geometric characteristics are in accord with ASME Y14.5M.
6 NUT DESIGNS AND PROPERTY CLASSES
There are three basic designs for prevailing-torque nuts. (a) all-metal, one-piece construction nuts which de- rive their prevailing-torque characteristics from con- trolled distortion of the nut thread and/or body (b) metal nuts which derive their prevailing-torque characteristics from the addition or fusion of a non- metallic insert, plug, or patch in their threads (c) top insert, two-piece construction nuts which de- rive their prevailing-torque characteristics from an in- sert, usually a full ring of nonmetallic material, located and retained in the nut at its top surface The two nut designs defined in paras. 6(a) and (b) have the same dimensional requirements and are des- ignated “all-metal type” in Tables 1 and 2. Nut design 6(c) is designated “top insert type” in Tables 1 and 2.
7 WIDTH ACROSS FLATS
The width across flats shall be the distance, measured perpendicular to the axis of the nut, between two op- posite wrenching flats. The maximum width across flats may be exceeded by 0.05 mm to allow for nut defor- mation caused by 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 fea- ture. At maximum material condition the axis of the hexa- gon shall be located at true position with respect to the axis of the thread pitch diameter within a tolerance zone having a diameter equivalent to 4% of the maximum width across flats.
8 THICKNESS
The nut thickness shall be the overall distance, meas- ured 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.