Which material is not commonly mentioned for wire rope pulley/sheave applications?

In wire rope pulley or sheave applications, plastic is not commonly mentioned among the traditional materials used. The typical materials for pulleys include metals with high strength and durability, necessary for handling heavy loads and ensuring safety and effectiveness in operation.

Iron is favored for its strength and cost-effectiveness, making it suitable for heavy-duty applications. Copper alloys may be used in specific instances where corrosion resistance and conductivity are important, such as in specialized applications.

Paper, while it may be used in less conventional applications, does not possess the necessary strength or durability for standard pulley systems, making it an unlikely option.

The selection of materials in this context prioritizes mechanical properties such as tensile strength, fatigue resistance, and impact resistance, which are critical for performances in demanding environments. Plastic, while lightweight and corrosion-resistant, typically lacks the required mechanical strength and resilience needed for wire rope applications, therefore making it less common in this particular use case.