Technical specification of air duct
1 General provisions
1.0.1 This specification is formulated with a view to standardize the fabrication, installation, inspection and test methods of air ducts, to ensure safety and applicability, advanced technology, cost effectiveness, rationality and convenience for construction, and to assure a good engineering quality.
1.0.2 This specification is applicable to the fabrication and installation of metal or nonmetallic ducts used for ventilation and air conditioning works for newly constructed, expanded and renovated industrial and civil buildings (referred to as “air ducts”).
1.0.3 In addition to this specification, the technical and quality requirements for the fabrication and installation of air ducts shall also meet the requirements of the current relevant compulsory standards of the nation.
2 General requirements
2.0.1 The air ducts shall be fabricated and installed in accordance with the design drawings, contracts and relevant technical standards. In case of any change, there shall be a notice of design or contract change or a technical approval verification.
2.0.2 Before the construction of the air duct system, the construction unit shall coordinate with the development unit, supervision unit, EPC and design units about the position and direction of the air duct and other pipelines, and check the holes reserved for installation, etc. During the construction, the construction unit shall cooperate with personnel of civil engineering and other professional work.
2.0.3 Sheets, profiles and other main finished materials for fabrication and installation of air ducts shall meet the requirements of the current national standards for design and related products, and shall be provided with the ex-factory inspection certificates. During approaching, materials shall be checked and accepted according to the current relevant national standards.
2.0.4 Air ducts supplied as finished products shall be provided with corresponding qualification certificates, including quality certificate of main material, strength and leakage test reports of air duct (nonmetallic air ducts shall also be provided with fire protection and health test certification reports). The performance test methods of air ducts supplied as finished products shall meet the requirements of Annex A to this specification.
2.0.5 Energy-saving, high-efficiency and mechanically processing technology should be preferred for air duct fabrication.
2.0.6 The measuring and testing instruments for the fabrication and installation of air ducts shall be in a conforming state and within the effective inspection period.
2.0.7 Air ducts of concealed works shall be checked, accepted and approved by the supervisor before concealment.
2.0.8 After the installation of air duct system, the leakage test shall be carried out by the system category, with a test method specified in the Annex B to this specification.
2.0.9 Air duct system may be classified into the following three categories according to its working pressure (P):
1 Low pressure system with P≤500Pa;
2 Medium pressure system with 500Pa
1500Pa.
2.0.10 Outside length (or outside diameter) should be the designated dimension for metal air ducts, and inside length (or inside diameter) should be the designated dimension for nonmetallic air ducts. Common specifications of side length of rectangular air duct shall meet those specified in Table 2.0.10-1, and the ratio of long side to short side shall not be greater than 4:1. Specifications of circular air ducts shall meet those specified in Table 2.0.10-2, and the basic series are preferred.
Table 2.0.10-1 Common specifications of rectangular air ducts (mm)
Side length of air duct
120 320 800 2000 4000
160 400 1000 2500 -
200 500 1250 3000 -
250 630 1600 3500 -
?
Table 2.0.10-2 Specifications of circular air ducts (mm)
3 Air duct fabrication
3.1 General requirements
3.1.1 Metal sheets shall meet the following requirements:
1 The steel sheets shall be flat and smooth in surface, uniform in thickness, and free from defects such as cracks and scars, whose material shall conform to the current national standard GB 13237 Cold-rolled quality carbon structural steel sheets and strips or GB 710 Hot-rolled quality carbon structural steel sheets and strips.
2 Galvanized steel sheets (strips) should be mechanically engaged, and the galvanized coating is made of material above 100# (the mean of three-point test on both sides shall not be less than 100g/m2), and the material shall meet the requirements of the current national standard GB 2518 Continuous hot-dip zinc-coated steel sheets and strips.
3 Austenitic stainless steel shall be used for stainless steel sheet, whose surface shall be free from obvious defects such as scratches, scuffing, spots and pits, and whose material shall meet the requirements of the current national standard GB 3280 Cold rolled stainless steel sheets and plates.
4 The aluminium sheet shall be pure aluminium sheet or rust-proof aluminium alloy sheet, whose surface shall be free from obvious defects such as scratches, scuffing, spots and pits and whose material shall conform to the current national standard GB/T 3880 Aluminium and aluminium alloy rolled sheet.
3.1.2 Metal structural steels shall meet the requirements of the current national standards GB 9787 Hot-rolled equal-leg angle steel — Dimensions, shape, weight and tolerances, GB 704 Dimensions, shape, weight and tolerances for hot-rolled flats, GB 707 Hot-rolled channel steel — Dimensions, shape, weight and tolerances, GB 702 Hot-rolled round and square steel bars — Dimension, shape, weight and tolerance respectively.
3.1.3 The material for nonmetallic air ducts shall meet the following requirements:
1 The combustion performance of nonmetallic air duct materials shall meet the requirements of incombustible grade A or flame retardant grade B1 in the current national standard GB 8624 Classification for burning behavior of building materials and products.
2 The surface aluminium foil material of composite material shall meet the requirements of the current national standard GB 3198 Aluminium foil for general purpose, and its thickness shall not be less than 0.06mm. When the aluminium foil layer is compounded with reinforcing materials, its thickness shall not be less than 0.012mm.
3 The composite layer of composite plate shall be securely bonded. Defects such as delamination and collapse on one side of the outer surface of the plate shall not exceed 6‰, and the internal insulation materials shall not be exposed.
4 The combustion performance of aluminium foil heat-sensitive, pressure-sensitive tapes and adhesives shall meet the flame retardant grade B1 and shall be used within the service life. The adhesives shall match the material for air duct and meet the requirements of environmental protection.
5 The width of aluminium foil pressure-sensitive and heat-sensitive tapes shall not be less than 50mm. The thickness of aluminium foil shall not be less than 0.045mm. The 180° peeling strength of aluminium foil pressure-sensitive sealing tape shall not be lower than 0.52N/mm.
The ironing surface of aluminium foil heat-sensitive tape shall have a temperature-sensitive color point, and the color changes when heated to 150°C. In the 180° peeling strength test of heat-sensitive sealing tape, the peeling strength shall not be lower than 0.68N/mm.
6 Unplasticized polyvinyl chloride (PVC-U) plates shall meet the requirements of the current national standards GB/T 4454 Rigid polyvinyl chloride laminated plates or GB/T 13520 Unplasticized polyvinyl chloride extruded plates. The combustion performance of the plates shall be flame retardant grade B1. PVC-U plates shall be free from defects such as bubbles, delamination, carbonization, deformation and cracks.
7 Technical parameters and applicable scope of nonmetallic air duct sheets shall meet those specified in Table 3.1.3.
Foreword ii
1 General provisions
2 General requirements
3 Air duct fabrication
3.1 General requirements
3.2 Steel air duct
3.3 Stainless steel air duct
3.4 Aluminium air duct
3.5 Phenolic aluminium foil compound air duct and polyurethane aluminium foil compound air duct
3.6 Glass fiber compound air duct
3.7 Inorganic FRP air ducts
3.8 PVC-U air duct
3.9 Air duct with air cleaning and conditioning system
3.10 Air duct fittings
3.11 Flexible air duct
4 Installation of air duct
4.1 General requirements
4.2 Fabrication and installation of supports and hangers
4.3 Sealing of air duct Connection
4.4 Installation of nonmetallic air duct
4.5 Installation of nonmetallic air duct
4.6 Installation of flexible air duct
4.7 Installation of air duct of purified air cleaning system
5 Air duct inspection
5.1 General requirements
5.2 Dominant items
5.3 General items
Annex A Test method for compressive strength and air leakage rate of air duct
Annex B Test method for air duct system light leakage detection and air leakage rate
Explanation of wording in this specification
1 總則
1.0.1 為了規范風管的制作、安裝、檢驗和試驗方法,做到安全適用、技術先進、經濟合理、方便施工,確保工程質量,制定本規程。
1.0.2 本規程適用于新建、擴建和改建的工業與民用建筑的通風與空調工程用金屬或非金屬管道(簡稱風管)的制作與安裝。
1.0.3 風管制作與安裝的技術與質量要求,除應符合本規程外,尚應符合國家現行有關強制性標準的規定。
2 通用規定
2.0.1 風管的制作與安裝應按設計圖紙、合同和相關技術標準的規定執行,發生變更必須有設計或合同變更的通知書或技術核定簽證。
2.0.2 風管系統施工前,施工單位應與建設單位、監理、總承包和設計等單位協調風管與其他管線管路位置走向,核對安裝預留孔洞等。施工中應與土建及其他專業工種相互配合。
2.0.3 風管制作與安裝所用板材、型材以及其他主要成品材料,應符合設計及相關產品國家現行標準的規定,并應有出廠檢驗合格證明。材料進場時應按國家現行有關標準進行驗收。
2.0.4 以成品供貨的通風管道應具有相應的合格證明,包括主材的材質證明、風管的強度及嚴密性檢測報告(非金屬風管還需提供消防及衛生檢測合格的報告)。成品供貨風管的性能試驗方法應符合本規程附錄A的規定。
2.0.5 風管制作宜優先選用節能、高效、機械化加工制作工藝。
2.0.6 風管制作與安裝所使用的計量器具及檢測儀器應處于合格狀態并在有效檢定期內。
2.0.7 隱蔽工程的風管在隱蔽前必須經監理人員驗收及認可簽證。
2.0.8 風管系統安裝完畢,應按系統類別進行嚴密性試驗,其試驗方法應符合本規程附錄B的規定。
2.0.9 風管系統按其工作壓力(P)可劃分為以下三個類別:
1 低壓系統P≤500Pa;
2 中壓系統500Pa<P≤1500Pa;
3 高壓系統P>1500Pa。
2.0.10 金屬風管宜以外邊長(或外徑)為標注尺寸,非金屬風管宜以內邊長(或內徑)為標注尺寸。矩形風管邊長的常用規格應符合表2.0.10-1的規定,其長邊與短邊之比不宜大于4:1。圓形風管規格應符合表2.0.10-2的規定,并優先選用基本系列。
表2.0.10-1 矩形風管常用規格(mm)
風管邊長
120 320 800 2000 4000
160 400 1000 2500 —
200 500 1250 3000 —
250 630 1600 3500 —
表2.0.10-2 圓形風管規格(mm)
風管直徑
基本系列 輔助系列 基本系列 輔助系列
3 風管制作
3.1 一般規定
3.1.1 金屬板材應符合下列規定:
1 鋼板表面應平整光滑,厚度應均勻,不得有裂紋結疤等缺陷,其材質應符合現行國家標準《優質碳素結構鋼冷軋薄鋼板和鋼帶》GB 13237或《優質碳素結構鋼熱軋薄鋼板和鋼帶》GB 710的規定。
2 鍍鋅鋼板(帶)宜選用機械咬合類,鍍鋅層為100號以上(雙面三點試驗平均值不應小于100g/m2)的材料,其材質應符合現行國家標準《連續熱鍍鋅薄鋼板和鋼帶》GB2518的規定。
3 不銹鋼板應采用奧氏體不銹鋼材料,其表面不得有明顯的劃痕、刮傷、斑痕和凹穴等缺陷,材質應符合現行國家標準《不銹鋼冷軋鋼板》GB 3280的規定。
4 鋁板應采用純鋁板或防銹鋁合金板,其表面不得有明顯的劃痕、刮傷、斑痕和凹穴等缺陷,材質應符合現行國家標準《鋁及鋁合金軋制板材》GB/T 3880的規定。
3.1.2 金屬型鋼應分別符合現行國家標準《熱軋等邊角鋼尺寸、外形、重量及允許偏差》GB 9787、《熱軋扁鋼尺寸、外形、重量及允許偏差》GB 704、《熱軋槽鋼尺寸、外形、重量及允許偏差》GB 707和《熱軋圓鋼和方鋼尺寸、外形、重量及允許偏差》GB 702的規定。
3.1.3 非金屬風管材料應符合下列規定:
1 非金屬風管材料的燃燒性能應符合現行國家標準《建筑材料燃燒性能分級方法》GB 8624中不燃A級或難燃B1級的規定。
2 復合材料的表層鋁箔材質應符合現行國家標準《工業用純鋁箔》GB 3198的規定,厚度不應小于0.06mm。當鋁箔層復合有增強材料時,其厚度不應小于0.012mm。
3 復合板材的復合層應粘接牢固,板材外表面單面的分層、塌凹等缺陷不得大于6‰,內部絕熱材料不得裸露在外。
4 鋁箔熱敏、壓敏膠帶和膠粘劑的燃燒性能應符合難燃B1級,并應在使用期限內。膠粘劑應與風管材質相匹配,且應符合環保要求。
5 鋁箔壓敏、熱敏膠帶的寬度不應小于50mm。鋁箔厚度不應小于0.045mm。鋁箔壓敏密封膠帶180°剝離強度不應低于0.52N/mm。
鋁箔熱敏膠帶熨燙面應有加熱到150℃時變色的感溫色點。熱敏密封膠帶180°剝離強度試驗時,剝離強度不應低于0.68N/mm。
6 硬聚氯乙烯板材應符合現行國家標準《硬質聚氯乙烯層壓板材》GB/T 4454或《硬質聚氯乙烯擠出板材》GB/T 13520的規定。板材的燃燒性能應為難燃B1級。硬聚氯乙烯板材不應有氣泡、分層、碳化、變形和裂紋等缺陷。
7 非金屬風管板材的技術參數及適用范圍應符合表3.1.3的規定。
表3.1.3 非金屬風管板材的技術參數及適用范圍
風管類別 保溫材料密度(kg/m3) 管板厚度(mm) 燃燒性能 強度(MPa) 適用范圍
酚醛鋁箔復合板風管 ≥60 ≥20 B1級 彎曲強度≥1.05 工作壓力小于或等于2000Pa的空調系統及潮濕環境
聚氨酯鋁箔復合板風管 ≥45 ≥20 彎曲強度≥1.02 工作壓力小于或等于2000Pa的空調系統、潔凈系統及潮濕環境
玻璃纖維復合板風管 ≥70 ≥25 — 工作壓力小于或等于1000Pa的空調系統
無機玻璃鋼 水硬性無機玻璃鋼風管 ≤1700 見表3.7.3-1、2、3 A級 彎曲強度≥70 低、中、高壓空調及防排煙系統
氯氧鎂水泥風管 ≤2000 A級 彎曲強度≥65
硬聚氯乙烯風管 1300~1600 見表3.8.1-1、2 B1級 拉伸強度≥34 潔凈室及含酸堿的排風系統
3.1.4 金屬風管板材連接形式及適用范圍應符合表3.1.4的規定。
表3.1.4 金屬風管板材連接形式及適用范圍
名稱 連接形式 適用范圍
單咬口
內平咬口 低、中、高壓系統
外平咬口 低、中、高壓系統
聯合角咬口 低、中、高壓系統矩形風管及配件四角咬接
轉角咬口 低、中、高壓系統矩形風管或配件四角咬接
按扣式咬口 低、中壓矩形風管或配件四角咬接低壓圓形風管
立咬口 圓、矩形風管橫向連接或縱向接縫圓形彎頭制作不加鉚釘
焊接 見圖3.2.1 低、中、高壓系統
表3.1.5-1 金屬矩形風管連接形式及適用風管邊長
連接形式 附件規格(mm) 適用風管邊長(mm)
角鋼法蘭 M6螺栓 L25×3 低壓風管 中壓風管 高壓風管
≤1250 ≤1000 ≤630
M8螺栓 L30×3 ≤2000 ≤2000 ≤1250
M8螺栓 L40×4 ≤2500 ≤2500 ≤1600
M8螺栓 L50×5 ≤4000 ≤3000 ≤2500
薄鋼板法蘭 彈簧夾式
插接式
頂絲卡式 彈簧夾板厚度大于或等于1.0mm 頂絲卡厚度大于或等于3mm
頂絲螺絲M8 h=25、δ1=0.6 ≤630 ≤630 —
h=25、δ1=0.75 ≤1000 ≤1000 —
h=30,δ1=1.0 ≤2000 ≤2000 —
h=40、δ1=1.2 ≤2000 ≤2000 —
組合式 頂絲卡厚度大于或等于3mm h=25、δ2=0.75 ≤2000 ≤2000 —
h=30、δ2=1.0 ≤2500 ≤2000 —
S形插條 平插條 大于風管壁厚度且大于或等于0.75mm ≤630 — —
立插條 大于風管壁厚度且大于或等于0.75mm
h≥25 mm ≤1000 — —
C形插條 平插條 大于風管壁厚度且大于或等于0.75mm ≤630 ≤450 —
立插條 大于風管壁厚度且大于或等于0.75mm
h≥25mm ≤1000 ≤630 —
直角插條 等于風管壁厚度且大于或等于0.75mm ≤630 — —
立聯合角形插條 等于風管壁厚度且大于或等于0.75mm
h≥25mm ≤1250 — —
立咬口 咬口包邊板厚度等于風管壁厚度
h≥25mm ≤1000 ≤630 —
注:h為法蘭高度,δ1為風管壁厚度,δ2為組合法蘭板厚度。
表3.1.5-2 金屬圓形風管連接形式及適用范圍
連接形式 附件規格(mm) 連接要求 適用范圍
角鋼法蘭連接 L25×3
L30×3
L40×4 法蘭與風管連接采用鉚接或焊接 低、中、高壓風管
承插連接 普通 — 插入深度大于或等于30mm,應有密封措施 直徑小于700mm的低壓風管
角鋼加固 L25×3
L30×4 插入深度大于或等于20mm,應有密封措施 低、中壓風管
壓加強筋 — 插入深度大于或等于20mm,應有密封措施 低、中壓風管
芯管連接 芯管板厚度大于或等于風管壁厚度 插入深度大于或等于20mm,應有密封措施 低、中壓風管
立筋抱箍連接 抱箍板厚度大于或等于風管壁厚度 風管翻邊與抱箍應匹配,結合緊固嚴密 低、中壓風管
抱箍連接 抱箍板厚度大于或等于風管壁厚度 管端應對正,
抱箍應居中 低、中壓風管
抱箍寬度大于或等于100mm
表3.1.6 非金屬矩形風管連接形式及適用范圍
非金屬風管連接形式 附件材料 適用范圍
45°粘接 鋁箔膠帶 酚醛鋁箔復合板風管、聚氨酯鋁箔復合板風管
b≤500mm
榫接 鋁箔膠帶 丙烯酸樹脂玻璃纖維復合風管
b≤1800mm
槽形插接連接 PVC 低壓風管b≤2000mm
中、高壓風管b≤1600mm
工形插接連接 PVC 低壓風管b≤2000mm
中、高壓風管b≤1600mm
鋁合金 b≤3000mm
外套角鋼法蘭 L25×3 b≤1000mm
L30×3 b≤1600mm
L40×4 b≤2000mm
c形插接法蘭
(高度25~30mm) PVC鋁合金 b≤1600mm
鍍鋅板厚度大于或等于1.2mm
“h”連接法蘭 PVC鋁合金 用于風管與閥部件及設備連接
注:b為風管邊長。
3.1.5 金屬矩形風管連接形式及適用風管邊長、圓形風管的連接形式及適用范圍應分別符合表3.1.5-1、3.1.5-2規定。
3.1.6 非金屬矩形風管連接形式及適用范圍應符合表3.1.6的規定。
3.1.7 非金屬風管在使用膠粘劑或密封膠帶前,應清除風管粘貼處的油漬、水漬、灰塵及雜物等。
3.1.8 風管及法蘭制作的允許偏差應符合表3.1.8的規定。
表3.1.8 風管及法蘭制作的允許偏差(mm)
風管邊長b或直徑D 允許偏差
邊長或直徑偏差 矩形風管表面平面度 矩形風管端口對角線之差 法蘭或端口端面平面度 圓形法蘭任意正交兩直徑
金屬風管 b(D)≤320 ≤2 ≤10 ≤3 ≤2 ≤2
b(D)>320 ≤3
非金屬風管 b(D)≤320 ≤2 ≤3 ≤3 ≤2 ≤3
320<b(D)≤2000 ≤3 ≤5 ≤4 ≤4 ≤5
3.2 鋼板風管
3.2.1 鋼板矩形風管的制作應符合下列要求:
1 矩形風管及其配件的板材厚度不應小于表3.2.1-1的規定。
表3.2.1-1 鋼板矩形風管板材厚度(mm)
風管邊長b 一般用途風管 除塵系統風管
中、低壓系統 高壓系統
b≤320 0.5 0.75 1.5
320<b≤450 0.6 0.75 1.5
450<b≤630 0.6 0.75 2.0
630<b≤1000 0.75 1.0 2.0
1000<b≤1250 1.0 1.0 2.0
1250<b≤2000 1.0 1.2 按設計
2000<b≤4000 1.2 按設計 按設計
注:1 本表不適用于地下人防及防火隔墻的預埋管。
2 排煙系統風管的板材厚度可按高壓系統選用。
3 特殊除塵系統風管的板材厚度應符合設計要求。
2 鍍鋅鋼板或彩色涂層鋼板的拼接,應采用咬接或鉚接,且不得有十字形拼接縫。彩色涂層鋼板的涂塑面應設在風管內側,加工時應避免損壞涂塑層,損壞的部分應進行修補。
3 焊接風管可采用搭接、角接和對接三種形式(圖3.2.1)。風管焊接前應除銹、除油。焊縫應熔合良好、平整,表面不應有裂紋、焊瘤、穿透的夾渣和氣孔等缺陷,焊后的板材變形應矯正,焊渣及飛濺物應清除干凈。
壁厚大于1.2mm的風管與法蘭的連接可采用連續焊或翻邊斷續焊。管壁與法蘭內口應緊貼,焊縫不得凸出法蘭端面,斷續焊的焊縫長度宜在30~50mm,間距不應大于50mm。
圖3.2.1 焊接風管焊縫位置
4 除塵系統風管與法蘭的連接宜采用內側滿焊、外側間斷焊。風管端面距法蘭接口平面的距離不應小于5mm。
5 風管加固應符合下列規定:
1)薄鋼板法蘭風管宜軋制加強筋,加強筋的凸出部分應位于風管外表面,排列間隔應均勻,板面不應有明顯的變形。
2)風管的法蘭強度低于規定強度時,可采用外加固框和管內支撐進行加固,加固件距風管連接法蘭一端的距離不應大于250mm。
3)外加固型材的高度不宜大于風管法蘭高度,且間隔應均勻對稱,與風管的連接應牢固,螺栓或鉚接點的間距不應大于220mm。外加固框的四角處,應連接為一體。
4)風管內支撐加固的排列應整齊、間距應均勻對稱,應在支撐件兩端的風管受力(壓)面處設置專用墊圈。采用管套內支撐時,長度應與風管邊長相等。
5)矩形風管剛度等級及加固間距宜按表3.2.1-2、表3.2.1-3、表3.2.1-4、表3.2.1-5、表3.2.1-6進行選擇和確定。
表3.2.1-2 矩形風管連接剛度等級
連接形式 附件規格(mm) 剛度等級
角鋼法蘭 L25×3 F3
L30×3 F4
L40×4 F5
L50×5 F6
薄鋼板法蘭 彈簧夾式
插接式
頂絲卡式 彈簧夾板厚度大于或等于1.0mm
頂絲卡厚度大于或等于3mm
頂絲螺絲M8 h=25、δ1=0.6 Fb1
h=25、δ1=0.75 Fb2
h=30、δ1=1.0 Fb3
h=40、δ1=1.2 Fb4
組合式 h=25、δ2=0.75 Fb3
h=30、δ2=1.0 Fb4
S形插條 平插條 大于風管壁厚度且大于或等于0.75 F1
立插條 大于風管壁厚度且大于或等于0.75
h≥25 F2