Are there straightness tolerances for ASTM F1554 anchor bolts?
The answer to this question is no. The ASTM F1554 specification defines tolerance ranges for various dimensional requirements such as thread dimensions, thread length variance, overall length, (and in the case of bent anchor bolts) bend section, hook length, and bend length. However, no tolerances are given for straightness. The reason for this is because the F1554 specification was written specifically to cover anchor bolts “..intended for anchoring structural supports to concrete foundations.” In real world terms, this means that anchor bolts manufactured under this specification are going to primarily be installed in concrete and are not intended for applications requiring tight dimensional tolerances. Because anchor bolts (whether straight rods, bent anchor bolts, or headed bolts) are going to have the majority of their length embedded in concrete, in practical terms, the only portion that needs to be straight is the threaded end projecting out of the concrete once it sets.
By way of comparison, typical fasteners do have straightness tolerances, as this can be an important consideration as bolts or screws may be used in any number of applications where straightness is a critical component. ASME B18.2.1 which covers dimensional criteria for square, hex, and heavy hex bolts and screws, states that for bolts up to 12” in length the maximum allowable camber is 0.006” per inch of bolt length. For bolts 12”-24” in length the maximum allowable camber is 0.008” per inch of bolt length.
Generally this is not an area of concern for anchor bolts. However, if your project has ASTM F1554 anchor bolts being utilized in a fashion where straightness may be a critical component, you may need the project engineer to define the straightness values required. If you have questions about your project requirements or need a quote, contact one of our experienced team of estimators.
F1554 Dimensional Tolerances
|Bolt Length Tolerance1||± 1" for lengths over 24"|
|± 1/2" for lengths 24" or less|
|Hook Length Tolerance||± 10% or ± 1/2" whichever is greater|
|Bend Angle||± 5°|
|Thread Series||Unified Coarse Thread Series per ANSI/ASME B 1.1|
|Thread Tolerance||Class 2A|
|Thread Length Tolerance||+1", -0"|
|1 Overall length of straight anchor bolts, or length to the inside of the hook.
** All tolerances are standard unless otherwise specified.