Regarding cast iron and chrome-plated piston rings, which statement is true?

In the context of piston rings made from cast iron and chrome plating, it is important to understand the properties and applications of each material. Cast iron piston rings are commonly used due to their strength, wear resistance, and ability to maintain a good seal against the cylinder walls. They are particularly effective in reducing oil consumption and providing longevity under high-stress conditions typically found in reciprocating engines.

Chrome-plated piston rings, on the other hand, offer a smoother surface that reduces friction and wear against the cylinder walls. The chrome plating enhances resistance to wear and helps maintain the ring’s effectiveness over time, especially in high-performance or high-temperature environments.

When both materials (cast iron and chrome-plated) are presented in true statements, it indicates that each is beneficial in its own right, serving different functions in an engine. Cast iron provides durability and sealing capacity, while chrome plating adds to the longevity and performance under various operating conditions.

Thus, both statements can indeed be true, confirming the validity of the answer that maintains both No. 1 and No. 2 as correct. Understanding this distinction helps clarify the roles of different piston ring materials in engine design and performance optimization.