Newest FAQs

ASTM vs SAE

What is the difference between ASTM and SAE Fastener Standards?

When looking at a bolt specification you may notice that some are ASTM standards, such as ASTM F1554, and some are SAE standards, such as SAE Grade 5 (a common bolt found in the SAE J429 specification). Outside the technical differences (mechanical requirements, chemical requirements, and other requirements) that vary between any fastener standard, the... Read more

Stainless Nuts and Galvanized Bolts

Can stainless steel nuts be used with galvanized bolts?

The use of stainless nuts with galvanized bolts is not advisable. Portland Bolt has fielded requests for galvanized bolts that have a stainless nut and washer as the hardware. Ideally, you would use a galvanized nuts and washers with a galvanized bolts and stainless bolts with stainless nuts and washers. Both types of nuts and... Read more

Intergranular Corrosion Test

What is an intergranular corrosion test?

In order to answer this question, we must first define what intergranular corrosion is. It is a type of corrosion where the grain boundaries of crystallites in austenitic steel are more susceptible to corrosion than the inside of the material. Grain boundaries can become depleted during the manufacturing of stainless steel round bar, the hot... Read more

SS304 or SS316 Bolts

Can I order bolts to Type 304 or 316 stainless steel?

Type 304 and Type 316 are very common stainless steel grades that just refer to a type of stainless steel. If you were to look for Type 304 or 316 stainless steel bolts in the ASTM Fastener Standards Manual you aren’t going to find them. That is because they are steel grades as opposed to... Read more

Black Bolt

9/16″ Structural Bolt Availability

Are 9/16” diameter F3125 Grades A325 and A490 structural bolts readily available?

No. The specification moves up in 1/8” increments starting at ½” diameter and maxing out at 1-1/2”. Under the old A325 – 09 specification, there was a reference about oversize limits on bolts and listed 9/16” diameter as a size. Since A325 bolts have been reclassified under the new F3125 specification, there is no longer... Read more

All Thread Rod in Tie Rod Assemblies

Can I use all thread rod for tie rod assemblies?

Yes and No. Traditionally, tie rod assemblies are used with thread each end rods and two clevises. They are designed to have a left-hand threaded end within the assembly in order to draw it tight. All thread rod possesses continuous right-hand thread from one end of the rod to the other. Here are the ways... Read more

Difference between F594 & A194 nuts

What is the difference between F594 and A194 nuts?

For this FAQ, we are focusing on the 304/316 alloys and their common, default strength conditions. Within both F594 and A194, there are many less common, exotic grades and multiple strength conditions. Exploring all possible permutations of all grades would be unnecessarily complicated. For more details, the actual ASTM standards can be purchased from ASTM,... Read more

Thread Class for All Thread Rod

Is all thread rod produced with a Class 2A thread?

There are three classes of thread fit associated with fasteners: Class 1A/1B, Class 2A/2B, Class 3A/3B. The “A” refers to the externally threaded fastener component, typically the bolt, while “B” refers to the internally threaded fastener component, usually a nut. As the number of thread class increases, the threading tolerances become more precise. Most construction... Read more

Heat-treatment After Forging

Do headed bolds receive heat treatment before or after the heads are forged?

Not all grades of bolts require heat-treating, but those specifications that do are heat-treated after the heads are forged. Heat-treating is performed in a controlled environment using specific quenching and tempering temperatures and durations. The bolts are then tested to ensure the strength of the heat-treated bolts meet the requirements of the given specification. Since... Read more

Shipping Quantities of +/- 10%

Why do some manufacturers have a policy of shipping quantities of +/- 10%?

Portland Bolt does not abide by the practice of shipping quantities of +/- 10%. We feel this policy is ludicrous. We ship exact quantities and the reason is explained below. Shipping +/- 10% is done as a cost-cutting measure by many manufacturers. Since several parts are lost during the manufacturing process (some are used for... Read more