Which compression ratio is associated with a high speed reciprocating compressor?

• A. 6:1
• B. 12:1
• C. 8:1
• D. 20:1

Answer: (C)

In high-speed reciprocating compressors, keeping the pressure rise per stroke moderate helps control heat buildup and mechanical stress. When the piston moves very fast, pushing the gas up by a large amount in one stage would generate a lot of heat and place more load on valves, pistons, and seals. A middle-range per-stage compression makes these stresses more manageable, improving efficiency and reliability at high speeds. It also allows multiple stages (with cooling between them) to reach the final pressure without overworking any single stage. Higher per-stage ratios would cause excessive heat and cooling needs for a high-speed unit, while lower ratios would require more stages and add complexity. So the best-fit concept is a moderate, mid-range per-stage ratio, which aligns with high-speed reciprocating compressors.