Does imported stock all thread rod meet ASTM A307 grade C?

Frequently, imported mild steel all thread rod will not meet ASTM A307 grade C. The three different grades of the A307 specification identify their intended application where grade C is embedded in concrete and used for anchoring purposes, grade B is used in cast iron flange connections, and grade A covers general applications. Normally, imported all thread rod is tested and certified to meet ASTM A307 grade A and will often meet A307 grade B. However, more often than not, the test reports that accompany this threaded rod lack a Yield Strength value that is required to determine its compliance with A307 grade C. Refer to the chart below for the difference in the mechanical requirements between ASTM A307 grades A, B, and C. Although there are subtle differences in the tensile strength requirements, the primary difference between these three grades of A307 is that grade C requires a minimum yield strength of 36,000 psi while grades A and B have no requirement. Therefore, unless a test has been performed to determine the yield strength, the threaded rod cannot be certified to meet ASTM A307 grade C.

Portland Bolt provides 100% domestically manufactured all thread rod which will meet not only grades A and B of the ASTM A307 specification, but grade C as well.

A307 Mechanical Properties

Grade Tensile, ksi Yield, min, ksi Elong %, min
A 60 min -- 18
B 60 - 100 -- 18
C* 58 - 80 36 23
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As you can see, there is no yield test performed on this import all thread rod, so it cannot be certified to ASTM A307C.

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    A307 all thread rod, lateral force is 2.3 kip/2 , concrete strength 4500psi. What is the embedded depth required?

    @Jonathan- Apologies, but we do not have any engineers on staff and so are unable to answer questions like this.

    @Manjit – You can find a brief summary on our website in the Technical Information/ASTM Specifications section. If you need the full specification, you will need to contact ASTM.

    @Ramon – Any low carbon mild steel should do the trick, you will just need to consult the chemistry and mechanical tables in ASTM A307 to make sure you are meeting the requirements. There is also a summary here on our website /technical/specifications/astm-a307/

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