Technical FAQs
Coupling Nut Thread Engagement
How much coupling nut thread engagement is required to achieve the strength of the rod?Unfortunately there appears to be no documented information on how much rod engagement into a coupling nut is required to achieve the strength of the rod or bolt being used with it. Coupling nuts are manufactured to the same ASTM specifications as regular hex nuts, and ASME B18.2.2 provides dimensional specifications for coupling nuts. Standard coupling... Read more
Anchor Bolts Too Low or High
What do I do if I poured my anchor bolts too low or too high?The answer can be found in AISC Design Guide 1,Section 2.11.3: “Anchor rod projections that are too short or too long must be investigated to determine if the correct anchor rods were installed. If the anchor rod is too short, the anchor rod may be projecting below the foundation. If the rod projection is too long,... Read more
Between Anchor Bolt Sleeves
What size anchor bolt sleeve do I use to fit a 1-1/8” diameter anchor bolt?This question is often brought to Portland Bolt’s attention by customers wondering how to install an anchor bolt sleeve with a 1-1/8” diameter rod. This issue arises due to the fact that anchor bolt sleeves are not manufactured in 1-1/8” diameter. We knew of two different solutions, but were left wondering which was the preferred... Read more
Stainless Steel F1554 Anchor Bolts
Do F1554 anchor bolts come in stainless steel?The answer to this question is no. As stated in Section 1.1, the F1554 specification covers various configurations of, “…carbon, carbon boron, alloy, or high-strength alloy steel anchor bolts.” In general terms, for a steel to be considered “stainless” it must contain at least 10.5% chromium as part of its chemical composition and will often... Read more
Galvanizing 8 Pitch Threads
Why won’t Portland Bolt manufacture galvanized bolts above 1-1/2” diameter with 8 TPI thread?Our two main concerns with providing galvanized bolts larger than 1-1/2” diameter with 8 threads per inch is the lack of overtap allowance standards for the mating nut and the potential for premature thread stripping due to the nut oversizing. Overtap Allowances All inch series hot dip galvanized hex nuts, regardless of grade, are tapped... Read more
Die Seams on Headed Bolts
Are die seams allowed on headed bolts?There are several differences between bolts intended for use in construction and more precision fasteners, such those used in an OEM application. One difference for headed bolts is the process in which the head is formed on the bolt and the resulting appearance of the bolts. Larger, construction headed bolts are typically made by hot-forging... Read more
Correcting Anchor Bolt Damage
If my already installed anchor bolts got bent by accident, is it OK to bend them back?The anchor rods in this photo were damaged because they were covered with snow and the equipment operator did not see them. Every situation is different, and we try to not make recommendations where bent anchors are concerned as we feel it is a question better answered by the project engineer, as he/she will be... 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
SS316/SS304 vs. SS316L/SS304L
What is the difference between SS316/SS304 and SS316L/SS304L?Stainless steel type 316 and type 304 are raw material grades for stainless steel. Stainless steel fasteners are sometimes referred to and ordered as their raw material grades (such as SS 316 and SS304) and sometimes referred to and ordered as their ASTM specification. The common ASTM specifications that cover stainless steel bolts are A193,... Read more
Beveled Washer Slope
How do I calculate the slope in degrees for a beveled washer?The slope of a beveled washer or a given segment represents how much the elevation changes over a certain distance. The higher the slope, the more steep the incline or decline. Slope is measured in degrees, ratios and grades. To find the slope in degrees, you need to make use of trigonometry ratios or more... Read more