Are there any other "high strength" bolts other an A325, A449 or A490? Would SAE Grade 5 and 8 qualify?

The term “high strength” is a somewhat ambiguous fastener term. Most people in the industry would interpret the phrase “high strength” to refer to any bolt that has been quenched and tempered (heat treated) to develop its strength. Additionally, the ASTM specification F1554 Grade 55 is commonly referred to as being manufactured from a “high strength, low alloy steel”, even though this material is not heat treated. Any grades on our Strength Requirements by Grade Chart with a “Q & T” in the Material & Treatment Column undergo heat treatment and would be considered high strength by most people in the fastener industry. Both SAE J429 Grades 5 and 8 have been quenched and tempered and would be considered “high strength” by most.

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10 comments

    @Mohammad- Grades 8.8 and 10.9 are both considered high strength bolts, but 10.9 is higher. Grade 8.8 is similar to SAE grade 5 or ASTM A449, whereas 10.9 is similar to SAE grade 8 or ASTM A354 BD.

    @Luke- There are many grades within ASME as well as SAE, so we’d need to know what grade from each you are wanting to substitute. Regardless, an engineer should always be consulted before any substitutions are made.

    good day sir
    could you please explain what is actually the different between the regular bolt and hight strength bolt? from the process and the composition commonly. thanks

    @Dineta – Low carbon bolts (regular) are made from low carbon, low strength steel, whereas high strength bolts are made from medium carbon or alloy steel and heat treated to achieve their higher strengths. We have summaries of both low carbon (A307) and high strength bolts (A325/A449/A490/A354/F1554) on our website.

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