The metal air duct is made of steel plate and the flange is made of profiled steel. When prefabricating, attention should be paid to whether the wrong material can be used. A section should be left at the connection of the variable-diameter accessories (such as tuyeres) and the blanking should be made and installed according to the actual size. Avoid rework, flange fabrication should be done in pairs to avoid bolt holes uneven in future installation.

　　1.1根據風管的尺寸，選擇不同的板材厚度，然后留足咬口余量、進行下料。

　　1.1 According to the size of air duct, choose different thickness of sheet, and then leave enough bite allowance for blanking.

　　1.2劃線方法要嚴密，做到角直、線平、等分準確、經常檢驗結合尺寸，達到交圈嚴格、尺寸正確的目的。

　　1.2 The method of marking should be strict, so that the angle, line level, equal parts are accurate, and the combined size is checked regularly, so as to achieve the purpose of strict intersection and correct size.

　　1.3剪切、倒角要正確，盡量減少誤差，操作時避免接縫、翻邊處重疊。

　　1.3 Shearing and chamfering should be correct to minimize errors and avoid overlapping of seams and flanges during operation.

　　1.4制作風管及部件時盡量采用咬口連接，因為咬口縫可以增加風管的強度。

　　1.4 When making air ducts and components, try to use bite joints, because bite joints can increase the strength of air ducts.

　　1.5根據不同的板材厚度選擇咬口的寬度和留量，咬口操作時，避免咬口不實，造成脹裂及半咬口現象。

　　1.5 Choose the width and retention of the bite according to the thickness of the plate. When the bite is operated, the false bite is avoided, resulting in swelling and half bite.

　　1.6當風管邊長過大，其管段在1.2米以上時應采取加固措施視具體情況采用角鋼框加固、角鋼加固大邊，內壁設置加固肋條的辦法加固。

　　1.6 When the side of the air duct is too long and the pipe section is over 1.2 meters, reinforcement measures should be taken to reinforce the large side with angle steel frame, angle steel and ribs on the inner wall.

　　1.7法蘭選用角鋼法蘭組焊。切斷時用型鋼切割機加工，在鉆床上鉆孔后，放在焊接平臺上焊接，以保證平直度。

　　1.7 Angle steel flange is selected for group welding. Section steel cutting machine is used for cutting. After drilling on the drilling machine, it is welded on the welding platform to ensure flatness.

　　1.8預制時將相鄰風管進行編號，增加功效并減少施工過程中的返工。

　　1.8 When prefabricating, the adjacent air ducts will be numbered to increase efficiency and reduce rework during construction.

　　1.9風管的規格，尺寸應符合設計要求，當外觀質量達到折角平直、圓弧均勻，兩端平行、無翹角，風管與法蘭連接牢固翻邊平整并緊貼法蘭。風管加固牢靠、整齊，間距適宜，均勻對稱。

　　1.9 The specifications and dimensions of air ducts shall meet the design requirements. When the appearance quality reaches the level of folding angle, uniform arc, parallel ends and no warping angle, the air ducts and flanges are firmly flanged and flat and close to flanges. The air duct reinforcement is reliable, neat, spacing is appropriate, uniform and symmetrical.

　　2在安裝風管前，障礙物已清理，地面無雜物的條件下進行施工。

　　2. Before installation of air duct, obstacles have been cleared and construction is carried out under the condition of no debris on the ground.

　　3檢查現場結構預留孔洞的位置、尺寸是否符合圖紙要求，有無遺漏現象，的孔洞應比風管實際尺寸每邊大于100MM。

　　3. Check whether the location and size of the reserved holes in the field structure conform to the requirements of the drawings and whether there are any omissions. The remaining holes should be larger than 100MM on each side of the actual size of the duct.

　　4作業地點要由相應的輔助設施，如梯子電源和防護裝置消防器材等。

　　4. Operating sites shall be provided with corresponding auxiliary facilities, such as ladder power supply and fire fighting equipment of safety protection devices.