Which key is preferred for transmitting a large amount of impact type torque in both directions of rotation?

• A. Woodruff key
• B. Feather key
• C. Gib-head key
• D. Tangent key

Answer: (D)

The tangent key is particularly advantageous for transmitting large amounts of impact type torque in both directions of rotation due to its design and placement. Its unique shape allows it to provide a robust grip, effectively resisting shear forces that can occur during torque application. When torque is applied, the key engages firmly with the shaft and the wheel or sprocket, allowing it to lock the two parts together securely, which is especially important in applications involving intermittent or sudden loads.

Furthermore, tangent keys are often utilized in applications where there are reversing or fluctuating loads, enhancing their capacity to handle torque in both rotational directions without failure. Their ability to effectively prevent slippage under such impact loads makes them a preferred choice in dynamic systems.

In comparison, other key types may not offer the same level of effectiveness under both directional torque. For instance, Woodruff keys and feather keys can be less effective in transmitting large torque due to their design constraints and the types of loads they are typically meant to support. Gib-head keys, while useful in certain contexts, also may not provide the same robustness for heavy impact situations. Therefore, the tangent key stands out as the optimal option for ensuring efficient and reliable torque transmission in both directions.