gas passage造句

• Development and application of u - shaped gas passage in fully mechanized face
  型瓦斯通道的研究与应用
• Exhaust gas passage with variable pressure : it is adopted to prevent foul air from toilet and kitchen ; check valve is added at the joint
  变压式排风：为防止卫生间、厨房排风井内的污风反窜到室内，排风道采用了变压式排气道，并在封到接口处增设了止回阀。