Which type of key is often used in automotive applications due to its strength?

• A. Woodruff key
• B. Feather key
• C. Sunk key
• D. Square key

Answer: (C)

The choice of a sunk key for automotive applications is an appropriate one due to its design and functionality. Sunk keys are typically machined into the shaft and the corresponding component, often providing a deeper engagement between the key and the connected parts. This increased engagement enhances the transmission of torque, allowing for a stronger connection that can withstand the dynamic forces present in automotive systems.

In applications where reliability and load-bearing capacity are critical, such as in engines or powertrains, using a sunk key can minimize the risk of slippage or failure. The depth of the sunk key provides more surface area contact, which contributes to its ability to handle higher loads and torsional stresses compared to other key types.

While other keys like Woodruff, feather, and square keys have their specific applications, they may not offer the same level of strength and secure fit that is essential for the rigorous conditions found in automotive environments.