The production and installation of purification ventilation ducts and components, and the calculation method of engineering quantity is the same as that of general ventilation ducts, using corresponding norms. However, for the installation of components, purification fees need to be calculated, with 35% of the corresponding component sub item installation base price as the purification fee, of which labor costs account for 40%. The cost of the essence sealing treatment between the purification pipeline and the building gap shall be calculated according to the actual situation.

圓形風管展開面積，不扣除檢查孔、測定孔、送風口、吸風口等所占面積，咬口重疊所占面積，咬口重疊部分也不增加。

The unfolded area of a circular air duct does not deduct the area occupied by inspection holes, measuring holes, air supply outlets, suction outlets, etc. The area occupied by overlapping bites does not increase, nor does the overlapping part of bites increase.

風管制作安裝定額中發蘭墊料是按各種材料品種綜合考慮的，不得換算。

The flange gasket material in the production and installation quota of air ducts is comprehensively considered based on various material types and cannot be converted.

整個通風系統設計采用漸縮管均勻送風者，圓形管按斷面平均直徑，矩形管按斷面平均周長套用相應規定子目，其人工乘以系數2.5。空氣幕送風管制作安裝，按矩形風管斷面平均周長套用相應風管規定子目，其人工成以系數3.0，期于不變。

The entire ventilation system is designed with uniform air supply through gradually reducing pipes. Circular pipes are designed according to the average diameter of the cross-section, while rectangular pipes are designed according to the average circumference of the cross-section using corresponding sub items. The labor force is multiplied by a coefficient of 2.5. The production and installation of air curtain air supply pipes shall be carried out according to the average circumference of the rectangular air duct section, and the corresponding sub items of the air duct shall be applied. The labor cost coefficient shall be 3.0, and the period shall remain unchanged.

風管長度計算，一律以施工圖所示線長度為準，包括彎頭、三通、變徑管、天圓地方管件長度。支管長度以支管線與主管線交接點為分界點。

The calculation of the length of the air duct shall be based on the centerline length shown on the construction drawing, including the length of elbows, tees, variable diameter pipes, and pipe fittings in circular areas. The length of the branch is divided by the intersection point between the centerline of the branch and the centerline of the main pipe.

風管制作材料的品種、規格、性能與厚度應符合設計圖紙和現行產品標準的規定。

The variety, specifications, performance, and thickness of air duct production materials should comply with the design drawings and current national product standards.

制作質量要求：

Production quality requirements:

風管的規格、尺寸符合設計要求；

The specifications and dimensions of the air duct meet the design requirements;

風管外觀質量應達到折角平直，圓弧均勻，兩端面平行，無翹角；

The appearance quality of the air duct should be flat and straight with uniform arcs, parallel at both ends, and no warping angles;

風管的內表面要做到表面光滑，嚴禁有橫向拼縫和在管內設加固筋或采用凸棱加固方法。盡量減少底部的縱向拼縫。矩形風管底邊小于800mm時，底邊不得有縱向拼縫。所有的螺母、螺栓、墊圈和鉚釘均應采用與管材性能匹配，采用不會產生電化學腐蝕的材料，或采用鍍鋅等；潔凈風管的咬口縫連接緊密，寬度均勻，無孔洞，半咬口及脹裂現象。

The inner surface of the air duct should be smooth, and it is strictly prohibited to have horizontal seams or install reinforcement bars or use convex reinforcement methods inside the duct. Minimize the longitudinal seams at the bottom as much as possible. When the bottom edge of a rectangular air duct is less than 800mm, there shall be no longitudinal seam at the bottom edge. All nuts, bolts, washers, and rivets should be made of materials that match the performance of the pipe material and do not cause electrochemical corrosion, or galvanized; The bite seam of the clean air duct is tightly connected, with a uniform width and no holes, semi bite, or expansion cracks.