"A490 bolts are more susceptible to brittle fracture than A325 bolts, which are 120/105 minimum tensile steel strength," the FHA says, quoting the Guide to Design Criteria for Bolted and Riveted Joints. "The use of A490 bolts should be thoroughly evaluated prior to being included in a structure."ASTM A490 bolts are heavy hex bolts made of alloy steel with a flat bearing surface, washer faced, and chamfered point. They are used in structural steel joints in heavy construction applications that require greater yield and tensile strengths than those of an A325 bolt are required.ASTM A490 and ASTM A490M are ASTM International standards for heavy hex structural bolts made from alloy steel. The imperial standard is officially titled Standard Specification for Structural Bolts, Alloy Steel, Heat Treated, 150 ksi Minimum Tensile Strength , while the metric standard (M) is titled Standard Specification for high-strength steel bolts, Classes 10.9 and 10.9.3, for Structural Steel Joints .Tension Control Bolts, TC Bolts or Twist Off Bolts are now the most popular choice in high-strength structural bolting and formally recognized by the AISC (American Institute of Steel Construction) and the RCSC (Research Council on Structural Connections) as an approved installation method.ASTM A490 Bolts are intended for used in structural connections similar to ASTM A325/A325M but being produced from alloy steel instead of medium carbon steel, possed high tensile strength. There are two versions of this specification; ASTM A490 covering imperial sized high tensile bolting and A490M for metric sized bolts.A490 is a astm international specification for heavy hex structural bolts. A490 covers two types of quenched and tempered, alloy steel heavy hex structural bolts having a tensile strength of 150 to 173 ksi. These bolts are intended for structural connections and are furnished in sizes 1/2&Heavy Hex Structural Bolts, A490, Type 1, ASTM A563 Grade DH Heavy Hex Nut, Plain The information below lists the required dimensional, chemical and physical characteristics of the products in this purchase order.First, grade A325 and A490 bolts are produced with a heavy hex head configuration which provides a wider bearing surface over which to distribute the load. Grade 5 and 8 bolts are produced to standard hex cap screw configuration and therefore cannot distribute the load as much as is needed for structural applications.
Original video found at https://www.youtube.com/watch?v=OpKwdzGLbjc.