ASME B18.16.6:2008 pdf download

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.
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.
6 WIDTH ACROSS FLATS
The width across flats shall be the distance measured perpendicular to the axis of the nut between two oppo- site wrenching flats.
11 MATERIAL, MECHANICAL, AND PERFORMANCE PROPERTIES
11.1 Material and Processes 11.1.1 Material. Carbon steel nuts shall conform to the requirements of Table 4. Alternate material may be used if agreed upon with the purchaser. The nylon insert material shall be sufficient to meet the prevailing-torque requirements of Tables 2 and 3 when tested as specified in para. 12.3. 11.1.2 Heat Treatment. Grade NE2 nuts shall not be heat treated. Other nut grades may be heat treated as necessary (see Table 5) to meet the mechanical and performance requirements of this Standard, except that they shall not be case hardened. 11.1.3 Finish. Nuts may be furnished plain (bare metal) or with a protective coating as specified by the purchaser. The performance of nuts that are furnished with a protective coating shall notdeteriorate when nuts are stored indoors for a period of 6 months.In cases where nuts are given a protective coating or are cleaned following delivery to the purchaser, the nut producer shall not be held responsible for failures of the nut to meet dimensional, mechanical, or performance requirements traceable to plating, coating, or cleaning practice. 11.1.4 Hydrogen Embrittlement. Nuts shall not be embrittled. When heat-treated nuts are electroplated or phosphate coated, appropriate plating or coating pro- cesses should be employed to avoid hydrogen embrittle- ment. If necessary, the product shall be suitably treated as soon as practicable afterplating orcoatingto preclude detrimental hydrogen embrittlement. 11.2 Mechanical Requirements 11.2.1 Proof Load. Nuts shall withstand the proof load specified for the applicable grade and thread series in Table 2 or 3 when tested as specified in para. 12.1. 11.2.2 Hardness. Nuts shall have a hardness con- forming to the limits specified for the applicable grade in Table 5 when tested as specified in para. 12.2.11.3 Performance Requirements 11.3.1 Prevailing-Torque. The prevailing-torque developed by nuts during their first installation, or any subsequent installation or removal, shall not exceed the maximumfirstinstallationtorquespecifiedforthe appli- cable grade in Table 2 or 3 when tested as specified in para. 12.3. In addition, minimum prevailing-torque generated by nuts during their first and fifth removals shall not be less than the respective removal torques specified for the applicable grade in Table 2 or 3.