What are the marking requirements for A449 bolts?

The ASTM A449 specification is somewhat ambiguous when it comes to the marking requirements. While the requirements are perfectly clear for hex bolts and studs, the verbiage doesn’t address head styles other than hex head, other bolt configurations such as U-bolts, or rods with threads on each end.

ASTM A449, Section 16.1, Manufacturers Identification reads as follows: “All hex cap screws and bolts and one end of studs 3/8″ in. and larger… shall be marked by the manufacturer with a unique identifier to identify the manufacturer…”

ASTM A449, Section 16.2.1, Type Identification reads similarly: “Type 1 hex cap screws and bolts and one end of Type 1 studs… shall be marked ‘A449’.”

The reasons bolts require marking is so that they are easily visually identifiable by the end user. While the wording in the specification may technically only address hex bolts and studs, logic would dictate the marking requirement would also extend to other configurations such as U-Bolts, headed bolts with different head styles, and rods with threads on each end.

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    What version or year was the information above based on? I have A449-00 and the Markings section is Section 15, and has more information and some different requirements from your information here. I also just found that there is a new A449-14. I am trying to determine if mine is so out of date I should buy the new version.
    Mine doesn’t show any requirement for A449 to be marked, but instead Type 1 and 2 to be identified by two different types of radial line markings, similar to what your sites shows for SAE J429 Grade 5.

    @Paul – Yes, the marking requirements changed, I believe with the -04 revision. Our FAQ above was written using the -10 revision. The -14 revision contains a few changes, however the marking requirements did not change again, they remain the same.

    @Gary- No, A449 bolts are not only not required to be tested, but the specifics about the test and the number of threads exposed almost prohibit the test from being done per the AASHTO/FHA written procedures.

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