ASME B18.16.6-2008 pdf download.Nylon Insert Locknuts (Inch Series).
1 INTRODUCTION 1.1 Scope This Standard covers the complete general, dimen- sional, mechanical, and performance data for carbon steel, inchseries nyloninsertlocknuts ofpropertygrades NE2, NE5, and NE8 designated as American National Standard. The inclusion of dimensional data in this Standard is not intended to imply that all of the locknut sizes in conjunction with the various options described herein are stock items. Consumers should consult with suppli- ers concerning lists of stock production nylon insert locknuts. 1.2 Comparison to ISO Standards There is no ISO inch standard for these products at this time. 2 REFERENCE STANDARDS The following is a list of publications referenced in this Standard. Unless otherwise specified, the reference standard(s) shall be the most recent issue at the time of order placement. ASME B1.1, Unified Inch Screw Threads ASME B1.3, Screw and Thread Gaging Systems for Dimensional Acceptability—Inch and Metric Screw Threads (UN, UNR, UNJ, M, and MJ) ASME B18.2.1, Square and Hex Bolts and Screws (Inch Series) ASME B18.12, Glossary of Terms for Mechanical Fasteners ASME B18.18.1, Inspection and Quality Assurance for General Purpose Fasteners ASME B18.18.2M, Inspection and Quality Assurance for High-Volume Machine Assembly Fasteners ASME B18.22.1, Plain Washers Publisher: The American Society of Mechanical Engineers (ASME), Three Park Avenue, New York, NY 10016-5990; Order Department: 22 Law Drive, P.O. Box 2300, Fairfield, NJ 07007-2300 ASTM B 117, Standard Practice for Operating Salt Spray (Fog) Apparatus ASTM E 18, Test Methods for Rockwell Hardness and Rockwell Superficial Hardness of Metallic Materials
ASTM F 436, Hardened Steel Washers ASTM F 812, Surface Discontinuities of Nuts (Inch Series) ASTM F 1941, Electrodeposited Coatings on Threaded Fasteners [Unified Inch Screw Threads (UN/UNR)] Publisher: American Society for Testing and Materials (ASTM International), 100 Barr HarborDrive, P.O. Box C700, West Conshohocken, PA 19428-2959 SAE J121, Decarburization in Hardened and Tempered Unified Threaded Fasteners SAE J409, Product Analysis — Permissible Variations from Specified Chemical Analysis of a Heat or Cast of Steel Publisher: Society of Automotive Engineers (SAE), 400 Commonwealth Drive, Warrendale, PA 15096-0001 3 TERMINOLOGY For definitions of other terms relating to fasteners or component features thereof used in this Standard, refer to ASME B18.12. 4 DIMENSIONS Unless otherwise specified, all dimensions in this Standard are inches and shall be as specified in Table 1 and sections 6 through 9. All dimensions apply before plating or coating is specified. When plating or coating is specified, the finished product dimensions shall be agreed upon between the supplier and purchaser. 5 NUT DESIGNS AND PROPERTY GRADES This Standard covers top insert, two-piece construc- tion nuts that derive their prevailing-torque characteris- tics from an insert, usually a full ring of nonmetallic material, located and retained in the nut at its top sur- face. These are designated as property grade NE2, NE5, and NE8 meeting the mechanical and performance requirements of Table 2 or 3.
12.2 Hardness Test The Rockwell hardness of a sample nut shall be deter- mined on the top face of the nut. The top surface of the nut shall be prepared by grinding and removing sufficient material from the top to eliminate the effects of plating, coating, or other surface conditions. Material removal shall also be such as to provide a flat area large enough to allow a hardness test to be made midway between the hex corner and the major diameter of the thread. The bearing surface of the nut shall be prepared parallel to the test surface with removal of plating or coating. Further preparation of the test specimen and the method of performing the test shall conform to ASTM E 18. For referee purposes, nut hardness shall be taken on a longitudinal sectionthrough the nutaxis withreadings taken as close as possible to the nominal major diameter of the nut thread. 12.3 Prevailing-Torque Test The prevailing-torque test shall be conducted at room temperature using a load measuring device (see para. 12.3.2). A test bolt (see para. 12.3.3) and/or hard- ened mandrel (see para. 12.1.2) shall be inserted in the load measuring device, and hardened washer (see para. 12.3.4) placed on the bolt or mandrel and the sam- ple nut then assembled on the bolt or mandrel. The nut shall be advanced until a minimum of three and a maximum of five full bolt or mandrel threads protrude through the top of the nut. At that time, the maximum torque shall be recorded. This torque shall not exceed the first installed prevailing-torque value as specified for the applicable grade and thread series in Table 2 or 3. The torque measuring device shall be in accordance with para. 12.3.1.