Answer: The advantages include no oil contamination, low maintenance costs, long service life, and high energy efficiency.
A. Price and brand B. Performance, price and brand C. Market share and technological innovation D. Production date and transportation method Answer: C. Market share and technological innovation
A. Water lubrication B. Oil lubrication C. No need for lubrication D. Special lubricant lubrication Answer: D Analysis: Oil-free air compressors usually use special lubricants to cool and lubricate parts to ensure the purity of compressed air.
A. Higher B. Lower C. Same as oil injection air compressor D. The answer cannot be determined: B Analysis: Oil-free air compressors usually consume less energy and improve energy efficiency due to reduced use of lubricating oil.
A. 5% B. 11% C. 20% D. 30% answer: B Analysis: For every 1000 meters increase in altitude, the air density drops by about 11%.
Answer: “Low pressure” refers to the compressor’s ability to operate at relatively low pressure levels, making it suitable for applications that require low-pressure compressed air.