承压风管漏风量
pressurized duct air-leakage
风管式户式中央空调系统
Residential central air conditioning duct system
风管输送系统
penumatic tube dispatch system
风管制安
wind making and installing
复合玻纤风管外扩（内护）层
outer (inner) surface layer for protection of composite glassfibre air duct