Each valve is fitted with 2 pressure test points, red strap indicating upstream (high pressure) and blue strap indicating downstream (low pressure) for differential pressure measurement.是什么意思_Each valve is fitted with 2 pressure test points, red strap indicating upstream (high pressure) and blue strap indicating downstream (low pressure) for differential pressure measurement.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句