Which of the following is NOT a grade of wire rope?

The correct answer is that High carbon steel is not recognized as a grade of wire rope. Wire rope grades are typically categorized based on specific properties and usages that define their strength and flexibility characteristics.

Traction steel, Mild plow steel, and Improved plow steel are established grades that classify wire rope according to their tensile strength, ductility, and applications in lifting and hoisting. For instance, Mild plow steel is known for its ability to handle moderate loads, whereas Improved plow steel offers enhanced strength and performance for more demanding tasks.

High carbon steel, while it may be used in some wire production contexts due to its hardness and tensile strength, does not fall under the specific classifications used for wire rope. The emphasis in wire rope grading centers on the specific uses and mechanical properties required for lifting and rigging applications, which might explain the common omission of high carbon steel from this classification system.