TC Bolts Praised For Fast Installation And Reliability At New Online Resource


New multimedia online guide highlights the advantages of TC bolts in steel construction. Self-calibration ensures proper fastener tension for reliable connections.

Construction professionals who are researching TC bolts have a new online multimedia resource page to consult. Published by Baco Enterprises Inc., the guide includes two informational videos and written content that explain the distinct advantages of tension control bolts as fasteners in steel construction.


Also known as twist-off bolts, TC bolts enable reliable steel-to-steel joint connections. They come as a complete fastener assembly that includes the nut and washer. During installation, the bolts self-calibrate to produce the correct amount of tension between the nut and bolt. Self-calibration occurs through the use of lubrication and the spline that sheers off once the bolt hits the tension that it was designed to achieve.

Fastener manufacturers use high-strength steel to make TC bolts in diameters from 5/8 of an inch to 1-1/8 inches. All lengths are available up to 8-1/2 inches. A325 TC bolts may be obtained in plain steel or galvanized steel. However, A490 TC bolts only come in plain steel.

In addition to the durability of TC bolts, construction companies also value the ability to install them quickly. Their design supports a substantially faster installation compared to hex bolts and rivets. In fact, builders can install TC bolts at three to four times the rate of other steel construction fasteners.

A power tool called a sheer wrench employs an internal socket to check for proper calibration during installation of a TC bolt. The spline on the bolt fits into the socket and breaks off as soon as the bolt reaches the proper tension.

Preinstallation inspection of TC bolts is critical for producing reliable connections. Professionals sourcing bolts for a construction project should buy from manufacturers and distributors with established reputations. Good quality control involves tolerance testing of random batches of TC bolts. Skidmore bolt testing is the accepted standard for confirming a bolt’s integrity. Sensitive equipment that measures tension checks the calibration of the bolt, nut, and washer at the moment the spline sheers off during installation.

Additional information about TC bolts is online at


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