All thread rod (ATR) is a common, readily available fastener that is used in multiple construction applications. Rods are continuously threaded from one end to the other and are frequently referred to as fully threaded rods, redi rod, TFL rod (Thread Full Length), and a variety of other names and acronyms. Rods are typically stocked and sold in 3′, 6’, 10’ and 12’ lengths, or they can be chopped to a specific length. All thread rod that is cut to shorter lengths are often referred to as studs or fully threaded studs.
The most common, readily available all thread rod is ASTM A307 Grade A and A193 Grade B7. These two grades are readily available in the marketplace all over the country and are mass produced. However, several other grades of all thread rod are common in the marketplace and nonstandard size and grade combinations can be manufactured for its many applications.
All thread rods are used in many different construction applications. The rods can be installed in existing concrete slabs and used as epoxy anchors. Short studs can be used coupled to another fastener to extend its length. All thread can also be used as fast alternatives to anchor rods, used for pipe flange connections, and used as double arming bolts in the pole line industry. There are many other construction applications not mentioned here in which all thread rod or fully threaded studs are used. Find out more about many of these applications here.
All thread rod is manufactured in 3 ways: mass-produced, cut-to-length, and cut thread. Common grades and diameters are mass produced and available across the country. Cut-to-length all thread rod uses mass-produced rods which are then cut to the finished length with the ends chamfered. Cut thread all thread rod is manufactured for special grades of steel that are not mass produced. These rods are cut slightly longer than the finished length, fully threaded, then cut to the finished length and chamfered on each end. For all manufacturing styles, the all thread rod can then be galvanized or coated per the customer’s requirements.
All thread rod or fully threaded studs have two critical dimensions consisting of diameter and length. The length of shorter pieces of all thread rod (studs) can be measured in overall length (OAL) or “first to first”. First to first measures the stud from its first complete thread on one end to its first complete thread on the other end, eliminating the chamfers on the ends of the studs in the length measurement. Thread pitch can also vary from Unified National Coarse, to 8UN, to Unified National Fine depending on the specification.
All thread rod is commonly available in plain steel, hot-dip galvanized and zinc plated. Plain finish all thread rod is often referred to as “black” and it is raw, uncoated steel. All thread rods that will be exposed to the outside elements may need to be hot-dip galvanized to prevent corrosion. Zinc plating can also be used as a corrosion-resistant coating, though a hot-dip galvanized coating will provide greater corrosion-resistance. Zinc plating is commonly used for aesthetic purposes since it can be plated in multiple colors and provides a consistent and shiny coating. For other types of coating used on all thread rod, please contact me.