Which item should never be substituted for the alloy pin of a shackle?

Which item should never be substituted for the alloy pin of a shackle?

• A. A rated pin from the same type
• B. DA bolt
• C. A common bolt
• D. An approved manufactured pin

Answer: (C)

Shackles rely on a pin that is precisely designed to carry the load through the shackle body. A common bolt lacks the correct dimensions, material properties, and thread design needed for safe use in that connection, and it can shear, bend, or loosen under load or vibration. That’s why it should never be used. Use a pin that is manufactured for the shackle and rated for its load, such as a rated pin of the same type or an approved manufactured pin. These pins match the shackle’s size, strength, and engagement requirements, keeping the load path intact and reducing the risk of failure.

Shackles rely on a pin that is precisely designed to carry the load through the shackle body. A common bolt lacks the correct dimensions, material properties, and thread design needed for safe use in that connection, and it can shear, bend, or loosen under load or vibration. That’s why it should never be used. Use a pin that is manufactured for the shackle and rated for its load, such as a rated pin of the same type or an approved manufactured pin. These pins match the shackle’s size, strength, and engagement requirements, keeping the load path intact and reducing the risk of failure.