Buyers of fasteners can consult a new resource published by Dyifo about A490 TC bolts. The TC bolts resource page provided by Dyifo features a video produced by BACO Enterprises, Inc. followed by a thorough discussion of A490 TC bolts and A325 TC bolts. Professionals sourcing fasteners for structural projects that include metal-to-metal connections can use the resource to evaluate the qualities of TC bolts. Due to the high-stress structural demands placed on these bolts, parts buyers should seek them out from reputable fastener manufacturers. Established manufacturers engage in rigorous testing to maintain quality and guarantee performance.
TC stands for the tension control design of these fasteners that are normally attached with a washer and nut. They also go by the term twist-off bolts. TC bolts can be recognized by their hexagon heads, diameters between 1/2 inch and 1-1/2 inches, and short threaded shafts. They possess a minimum tensile strength of 150,000 psi and comply with American Society for Testing and Material specifications.
The alloy steel construction of A490 TC bolts accounts for their superior strength. Although they share characteristics with A325 TC bolts that are made from medium carbon steel, A490 TC bolts remain the stronger option.
Workers use a shear wrench to install A490 TC bolts. The tool grips the nut and the spline on the bolt simultaneously. The wrench then applies torque to the nut and bolt. The manufacturer designs the spline so that it shears off once the fastener assembly reaches the proper tension. This feature earns TC bolts the label of self-calibrating. During manufacturing, the bolts receive a lubricating coating that enables the calibrated installation.
A490 TC bolts offer advantages over rivets and have become the standard fastener for metal infrastructure projects. Compared to rivets, TC bolts achieve a more secure connection. Installation can be accomplished faster due to the self-calibration.