The manufacture of ventilation pipes and accessories and the installation of pipes and accessories in a shut-off valve at the engineering port shall be made of welded steel plates with a thickness of 2 to 3 mm. Welds shall be complete, uniform and tight. Ventilation ducts shall be welded. The vent pipe and stop valve shall be connected with the sealing groove, and the contact shall be stable; Flange gasket shall be full circle non interface rubber sealing ring. The end of the engineering osmometer shall be provided with a downward elbow at the end of the protective closing door; The other end shall be located in the ventilator room or control room, and ball valve shall be installed. The interface of the pressure measuring pipe passing through the anti-virus channel shall be welded.

壓力排水管應由供水鑄鐵管，鍍鋅管，鍍鋅鋼管或UPVC塑料管製成。界麵應由亞麻籽或石棉水泥製成，不應使用水泥砂漿。連接到管螺紋的填料應由甘油和紅丹粉末混合製成。對於連接到91视频免费下载法蘭的墊圈，應在兩側使用石墨塗層石棉紙板，不得使用普通橡膠墊圈。

The pressure drainage pipe shall be made of cast iron pipe, galvanized pipe, galvanized steel pipe or UPVC Plastic pipe for water supply. The interface shall be made of flaxseed or asbestos cement, and cement mortar shall not be used. The packing connected to the pipe thread shall be made of a mixture of glycerol and red lead powder. For gaskets connected to pipe flanges, graphite coated asbestos paperboard shall be used on both sides, and ordinary rubber gaskets shall not be used.

通過91视频免费下载的中線找到臂杆的位置。單臂位於91视频免费下载的中線上。雙臂可以根據托盤的螺孔間距或91视频免费下载的中線對稱安裝。吊杆可以根據吊架的形式焊接到吊架上，也可以懸掛在吊架上。焊接後應塗防鏽漆。當濟南通風91视频免费下载較長並需要安裝一排支架時，可以先固定兩端，然後使用兩端的支架作為參考，通過電纜方法查找中間支架的高程。

Find the position of the arm through the center line of the pipe. The single arm is located on the center line of the pipe. The two arms can be installed symmetrically according to the screw hole spacing of the tray or the center line of the pipeline. The suspender can be welded to the hanger or hung on the hanger according to the form of the hanger. Anti rust paint shall be applied after welding. When the ventilation duct in Jinan is long and a row of supports need to be installed, fix both ends first, and then use the supports at both ends as a reference to find the elevation of the middle support through the cable method.