ASME B18-16.6 pdf download Nylon Insert Locknuts (Inch Series) 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...