NAAMS Fastener Components

NAAMS Fastener Components are essential for securing assemblies, with a product range that includes screws, bolts, pins, nuts, and washers. Metric fasteners feature a blue coating for quick and easy identification compared to standard sizes.

For the full catalog in PDF format, click on the link below.
NAAMS Fasteners Complete Catalog

FASTENER INSTALLATION AND TORQUING PROCEDURE (EXCLUDING SHOULDER SCREWS)
Provided to you by NAAMS Standards

GENERAL
• This standard applies only to Property Class 10.9 hex head and 12.9 socket head cap screws when used in steel, un-lubed, and where the head bears against a metal surface. Where the bearing surface is not a metal (e.g. UHMW plastic), the tightening specification for any fastener shall be “snug fit then 1/4 turn”.
• For purposes of uniformity in clamp loading, the calculations for the recommended installation torques listed below are based upon K = 0.20 for uncoated screws and K = 0.15 for blue-coated screws.
• Testing by reputable fastener manufacturers has proven that the use of split lock washers under heads of hardened screws may prevent achieving or retaining the desired preload in bolted joints.

INSTALLATION PROCEDURE
1. Use only new fasteners for first-time assembly.
2. Before installing the fastener, be sure that it is free of flaws and it is the correct property class.
Fasteners with flaws shall be marked with a white line drawn across the threads and discarded.
3. Fasteners may be tightened with any appropriate fastening device. Final torque shall be done with a calibrated torque wrench to the required value as follows:

4. After torquing is completed, draw a straight line (match mark) from the wall of the fastener head onto the seating surface using a white steel paint pen. Ensure that the line is easily visible for periodic inspection.
5. A fastener suspected of being over-torqued shall be marked as described in item 2 and discarded.
6. Do not torque fasteners at machine breakpoints until final installation.
7. Where safety wiring is specified, do not safety wire any screws until they have passed the torque audit?
8. If fasteners are in a position that a torque wrench cannot be used, the following steps shall be used:
a) Tighten the fastener until the joint surfaces have established a snug fit.
b) Mark the position of the fastener to the surface with a white steel paint pen.
c) Tighten the fastener 1/3 of a turn (120).
d) After torquing is completed, draw a straight line (match mark) from the wall of the fastener head onto the seating surface using a white steel paint pen. Ensure that the line is easily visible for periodic inspection.