Dane's FAQs

Ordering Bolts to ASTM A36

Can I order bolts to ASTM A36?

ASTM A36 is a very common steel standard that covers structural carbon steel shapes, plates and bars. Fasteners are not specifically included in the scope of A36, but that doesn’t stop engineers and contractors from asking for A36 bolts. Why is that an issue? The inherent problem with trying to order bolts to a ASTM... Read more

Metric to Imperial Grade Equivalents

What are the imperial/ASTM equivalents for metric fastener grades?

Both ASTM F568M and ISO 898-1 outline several grades of metric fastener, from low carbon/low strength, up to high strength/heat treated alloy grades. The equivalents listed below should be only considered as rough equivalents. Special care should be taken before substituting grades to make sure that an acceptable substitute is being used. For example, grade... Read more


Bolt Welding Guidelines

When is it acceptable to weld to bolts, and when it is prohibited?

Many grades of bolt gain their strength though a heat treating process, and the addition of heat during welding can adversely alter those strength properties. However, some lower strength grades are easily weldable when manufactured from weldable steel. In general, steel items which have been heat treated for strength should generally not be welded since... Read more


High Strength Turnbuckles

When designing vertical rod bracing system I would like to use F1554 grade 55 rod to achieve smaller diameters. But if I use a turnbuckle I am limited to the safe working load of that turnbuckle. Is there a higher capacity turnbuckle available?

You are correct that your capacity would be limited by the safe working load of the turnbuckle, but it would be limited to that regardless of the grade of steel used for the bracing rod. Let’s assume you are using mild steel, A307/A36 rods. The minimum yield strength of that material is 36,000 psi. Using... Read more

Stacking Washers with A325 Bolts

Is stacking of F436 washers acceptable with an A325 bolted connection?

Yes, in some cases the stacking of F436 washers seems to be allowed, but not in all cases. The Research Council on Structural Connections (RCSC) in Specification for Structural Joints Using High-Strength Bolts, December 31, 2009, page 16.2-12 says, “If necessary, the next increment of bolt length can be specified with ASTM F436 washers in... Read more

Torque Charts and Anchor Bolts

Do torque charts for tensioning fasteners apply to anchor bolts?

The AISC Steel Construction Manual, 13th Edition has this to say about anchor rod nut installation. “The majority of anchorage applications in buildings do not require special anchor rod nut installation procedures or pretension in the anchor rod. The anchor rod nuts should be “drawn down tight” as columns and bases are erected. This condition... Read more

Galvanizing High Strength Bolts

Can high strength bolts be hot-dip galvanized?

Some high strength bolts can be galvanized while others cannot. In the construction fastener industry, typically the phrase “high strength” refers to bolts that have been quenched and tempered (heat treated) to develop the proper strength requirements of a given specification. In many cases, low alloy steels like ASTM A572g50 or F1554g55 are called “high... Read more

Calculating Grade 8 Shear Strength

What is the shear strength of Grade 8 bolts?

A common question that we get here at Portland Bolt is in regards to the shear strength of bolts. The shear strength is the value at which the lateral stress on a bolt or screw causes it to fail. It is an important factor to take into consideration when designing structural steel or timber connections.... Read more

Thread Engagement

How much thread engagement is recommended, i.e. how many threads should extend beyond the nut?

This is a difficult question to answer. Depending on your application, the answer could be anywhere from 1/2 engagement, up to having two full threads extend beyond the nut. Look at these conflicting answers found in four separate technical publications. Federal Highway Administration, “Guidelines for the Installation, Inspection, Maintenance and Repair of Structural Supports for... Read more

Weight Gained from Galvanizing

How much weight is gained from hot-dip galvanizing bolts?

According to the American Galvanizers Association (AGA) the weight of an item on average will increase about 3.5% from the zinc added during the galvanizing process. However, the AGA goes on to say, “…that figure can vary greatly based on numerous factors. The fabrication’s shape, size, and steel chemistry all play a major role, and... Read more