Newest FAQs

Grade C Eliminated From ASTM A307

What happened to ASTM A307 Grade C?

One change with regard to specifications that will have a significant impact on the construction fastener industry is the August 2007 elimination of the grade C designation within the ASTM A307 specification. ASTM A307 is the standard specification for low carbon steel construction fasteners. Until recently, A307 had three grades A, B, and C. Grade... Read more

SAE Grade 8 vs ASTM A490

What are the differences in strength and application between SAE Grade 8 and ASTM A-490?

In some respects SAE J429 grade 8 bolts and ASTM A490 bolts are similar, and in other respects they are different. The first thing to address is the fact that these specifications are covered by different organizations. SAE (Society of Automotive Engineers) covers bolts for automotive, equipment, and OEM applications, whereas ASTM (American Society for... Read more

ASTM Letter Designations

What do the letters at the beginning of an ASTM standard signify?

Every ASTM standard is identified by a unique designation. It includes a capital letter (A – H), followed by a serial number ranging from one to four digits, a dash, and finally the year of issue. For example, a common bolt specification is A449 – 07a, although when specified the standard’s year designation is usually... Read more

Metric Bolts – We Convert

Do you manufacture metric bolts?

All bolts we manufacture are made to imperial measurements. The primary reason for this is because the steel used to make bolts is milled to imperial sizes. Even though metric measurements are almost exclusively used internationally, most raw materials are only available domestically in inches. Often projects, such as highways, bridges, and power plants specify... Read more

Clevis Pin Question

When using a clevis pin and using a cotter pin, or a spring pin, or a spring clip, or a retaining ring to capture the outer end, my practice has always been to place a washer under the retaining device to discourage deformation and/or loss of the retaining device due to rotation of the clevis pin. Who agrees out there?

It seems like this question is directed toward clevis pins that are used to connect control assemblies, linkages and perhaps hinges. In these applications where rotation of the clevis pin is anticipated, I agree that a washer would protect the retaining device from possible ‘side effects’ of the rotation. In the case of pins that... Read more

Grade 8 vs ASTM A325

Is a Grade 8 bolt the same as an ASTM A325?

ASTM A325 and SAE J429 grade 8 are not the same fastener. As a matter of fact, they couldn’t be more different. SAE (Society of Automotive Engineers) establishes specifications covering fasteners intended for use in automotive, OEM, and equipment applications, while ASTM (American Society for Testing and Materials) provides specifications for construction fasteners. There are... Read more

ASTM Tie Rod Standards

Is it appropriate to spec ASTM F1554 in place of A36 tie rods for higher strength applications? What are the lengths these rods come in, the availability of each grade, and cost differences?

Most ASTM standards address the recommended application of the fastener. There are often two or three different ASTM specifications with similar chemical and mechanical properties, but with differing applications. ASTM F1554 is a specification that is designed for anchor bolts embedded in concrete. Since your application is for tie rod assemblies, it would appear that... Read more

Structural Bolt Length Tolerance

According to section 9 of the ASME B18.2.6 specification that covers fasteners for use in structural applications, an A325 structural bolt can actually be produced .12” to .25” less than the published length and still meet the specification.

According to section 9 of the ASME B18.2.6 specification, which covers dimensional tolerances for hex bolts, A325 and A490 structural bolts can actually be produced between .12 to .25 of inch less than the published length and still meet the specification. This small difference isn’t much, but mass bolt producers save a significant amount of... Read more

How a Bolt Head is Formed

How is a bolt head formed?

What many people do not realize is that the head of a bolt is formed by heating the end of a piece of steel round bar and then forging (reshaping) the heated end into a head. The head is not welded on or otherwise “attached” to the end of the round bar. For example, the... Read more

ASTM A193-B7 Thread Pitch

What bolts are available in ASTM A193-B7 and what is the appropriate thread pitch to specify?

“My plant uses hex head cap screws, ASTM A193-B7 as standard. We typically stock the constant thread series 8 TPI fasteners above 1 inch diameter. However, many tapped items like expansion joints come with UNC thread counts, like 7 threads per inch (TPI) for 1-1/4″ diameter bolts. This causes a problem sometimes when fasteners don’t... Read more