NAAMS Fastener Components
NAAMS Fastener Components are used to keep everything together. Products range from screws and bolts to pins, nuts, and washers. Metric fasteners are coated blue to help you easily and quickly distinguish from standard sizes.
For the full catalog in PDF format, click on the link below.
NAAMS Fasteners Complete Catalog
| NAAMS Fastener | Dimensional Specs | Material Specs |
|---|---|---|
| Socket Head Cap Screws | ANSI B18.3.1M | ASTM A574M |
| Hex Head Cap Screws | ANSI B18.2.3.1M | ASTM F568M, Class 10.9 |
| Base Leveling Screws | M24 x 2.9 x 150 HHCS | Property Class 10.9 |
| Hex Nuts | ANSI B18.2.4.2M | ASTM A563M, Class 12 |
| Lock Nuts | ANSI B18.16.3M | ASTM A563M, Class 12 |
| Hex Jam nuts | ANSI B18.2.4.5M | ASTM A563M, Class 04 |
| Shoulder Screws | ANSI B18.3.3M | ANSI B18.3.3M |
| Socket Set Screws | ANSI B18.3.6M | Class 45H |
| Flat Head Cap Screws | ANSI B18.3.5M | ASTM F835M |
| Button Head Cap Screws | ANSI B18.3.4M | ASTM F835M |
| PullOut Dowel Pins | ISO 8735A | - |
| Flat Washers (M6 - M10) | - | Rc 38-45 through hardening |
| Flat Washers (M12 and Larger) | ASTM F436M | ASTM F436M |
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:
| Nominal Diameter and Thread Pitch | Recommended Installation Torque (Nm) | |||
|---|---|---|---|---|
| Uncoated | Coated | |||
| Property Class 10.9 | Property Class 12.9 | Property Class 10.9 | Property Class 12.9 | |
| M6 x 1.0 | 16 | 19 | 12 | 14 |
| M8 x 1.25 | 39 | 45 | 29 | 34 |
| M10X 1.5 | 76 | 89 | 58 | 68 |
| M12 X 1.75 | 134 | 156 | 100 | 120 |
| M16 X 2.0 | 331 | 387 | 250 | 290 |
| M20 X 2.5 | 644 | 760 | 485 | 570 |
| M24 X 3.0 | 1120 | 1308 | 840 | 985 |
| M30 X 3.5 | 2226 | 2595 | 1670 | 1960 |
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.
