Use our new bolt weight calculator to estimate the weight of a number of different bolts. This interactive tool includes calculations for headed bolts such as hex, square, and heavy hex. It also provides information for bent anchor bolts and straight rods. All you need to enter is the bolt type, diameter, length, and quantity. Click to start calculating.

A portion of the extensive San Francisco-Oakland Bay Bridge project has been completed. This billion dollar job extends from Oakland, California west towards San Francisco. The structure was built parallel to the existing Bay Bridge. At over a mile long it contains approximately 200 million pounds of structural steel. The Oakland Skyway will connect to the new self-anchored suspension span currently under construction. Click to continue

Question: Sometimes there are lines on the bolt head. What do they mean?

Answer: The lines on the head of a bolt indicate its grade. SAE J429 (Society of Automotive Engineers) bolts have radial lines, whereas ASTM (American Society for Testing and Materials) uses a combination of letters and numbers to indicate the grade. Click to continue.

Roll threading is an extrusion process in which steel round bar is forced between two dies to form the threaded portion of a fastener, instead of being removed as in cut threading. In this process, a bolt is manufactured from a reduced diameter round bar. For example, a 1" diameter bolt is manufactured from .912" diameter round bar. Click to continue.

The ASTM A490 specification covers quenched and tempered, alloy steel, heavy hex structural bolts from ½” diameter through 1½” diameter with a minimum 150 ksi tensile . These bolts are intended for use in structural connections and therefore have shorter thread lengths than standard hex bolts. Refer to the Structural Bolts page of our site for thread lengths and other related dimensions. A490 bolts are similar in application and dimensions to A325 heavy hex structural bolts but are made from an alloy steel rather than a medium carbon steel, resulting in a higher strength fastener. Click to continue.