idle production capacity

基本解释

Production capacity is grossly underused with many idle workers and machines obvious to any visitor to the state factory.
由於大量工人無所事事，大量機器閑置一邊，來蓡觀這家國有工廠的人很容易就能看出工廠生産力低下。
cai.jnu.edu.cn

Also, Chinese idle production of steel is greater than the production capacity of Japan and South Korea combined.
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Unlike other metals where production has been taken offline, there's no idle capacity in the nickel industry.
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He recently threatened to expropriate some 700 idle firms, along with more than 1, 000 working below capacity, unless their owners resumed full production.
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