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　　通風(fēng)管道工程安裝工藝

　　Installation process of ventilation duct engineering

　　1通風(fēng)管道工程施工準(zhǔn)備1、作業(yè)條件（1）一般送風(fēng)機(jī)系統(tǒng)和空調(diào)系統(tǒng)的安裝，要在建筑物圍護(hù)結(jié)構(gòu)施工完，障礙物已清理，地面無雜物的條件下進(jìn)行。（2）對空氣潔凈系統(tǒng)的安裝，應(yīng)在建筑物內(nèi)部安裝部件的地面已做好，墻面已抹灰完畢，室內(nèi)無灰塵飛揚(yáng)或有防塵措施的條件下進(jìn)行。（3）一般除塵系統(tǒng)風(fēng)管安裝宜在廠房的工藝設(shè)備安裝完或設(shè)備基礎(chǔ)已確定，設(shè)備連接器、罩體方位已知的情況下進(jìn)行。（4）檢查現(xiàn)場預(yù)留孔洞位置、尺寸應(yīng)符合圖紙要求，每邊比實際截面大100mm。（5）作業(yè)地點(diǎn)要有相應(yīng)的輔助設(shè)施，如梯子、架子、安全防護(hù)、消防器材，并有施工員的技術(shù)、質(zhì)量、安全交底。

　　1. Preparation for Construction of Ventilation Duct Engineering 1. Operating Conditions (1) The installation of the general air supply fan system and air conditioning system should be carried out after the construction of the building enclosure structure is completed, obstacles have been cleared, and there are no debris on the ground. (2) The installation of the air purification system should be carried out on the floor where the components are installed inside the building, the walls have been plastered, and there is no dust flying or dust prevention measures in the room. (3) The installation of air ducts for general dust removal systems should be carried out after the installation of process equipment in the factory or when the equipment foundation has been determined and the orientation of the equipment connectors and covers is known. (4) The position and size of the reserved holes on site should meet the requirements of the drawings, and each side should be 100mm larger than the actual cross-section. (5) The work site should have corresponding auxiliary facilities, such as ladders, shelves, safety protection, fire-fighting equipment, and technical, quality, and safety briefings for construction workers.

　　2、材質(zhì)要求（1）各種安裝材料應(yīng)具有出廠合格證明書或質(zhì)量鑒定文件及產(chǎn)品清單。（2）風(fēng)管成品不允許有變形、扭曲、開裂、孔洞、法蘭脫落、開焊、漏鉚、漏打螺栓孔等缺陷：（3）安裝的閥體、風(fēng)口等部件應(yīng)檢查調(diào)節(jié)裝置是否靈活，消聲片、油漆層有無損傷。（4）安裝使用的材料：螺栓、螺母、墊圈、墊料、密封條、自攻螺釘，拉鉚釘，焊條、各種帆布、無紡布、射釘、膨脹螺栓應(yīng)符合產(chǎn)品質(zhì)量要求。

　　2. Material requirements: (1) All installation materials should have factory certificates of conformity, quality appraisal documents, and product lists. (2) Finished air ducts are not allowed to have defects such as deformation, distortion, cracking, holes, flange detachment, open welding, missing rivets, missing bolt holes, etc.: (3) The installed valve body, air outlet and other components should be checked for flexibility of the adjustment device, and for damage to the sound-absorbing film and paint layer. (4) The materials used for installation: bolts, nuts, washers, gaskets, sealing strips, self tapping screws, rivets, welding rods, various canvases, non-woven fabrics, nails, and expansion bolts should meet the product quality requirements.

　　3、工器具主要工器具有：手錘、電錘、手電鉆、手鋸、電動雙刃剪、砂輪鋸、角向磨光機(jī)、臺鉆、電氣焊具、扳手、改錐、手剪、倒鏈、高凳、大繩、尖沖、射釘槍、刷子等。2通風(fēng)管道工程工藝流程1、鍍鋅薄鋼管風(fēng)管制作展開下料 → 剪切 → 倒角→ 咬口制作 → 風(fēng)管折方 → 成型 → 法蘭下料 → 法蘭焊接 → 法蘭打眼沖孔 → 鉚接翻邊；2、鍍鋅薄鋼管風(fēng)管、不銹鋼風(fēng)管安裝風(fēng)管搬運(yùn) → 支吊架安裝 → 干管安裝 → 立管安裝 → 支管安裝 → 漏光及漏風(fēng)量檢測 → 隱蔽工程驗收 → 防腐保溫 → 單機(jī)調(diào)試 → 綜合調(diào)試；

　　3. The main tools include: hand hammer, electric hammer, hand drill, hand saw, electric double-edged shear, grinding wheel saw, angle grinder, bench drill, electrical welding tool, wrench, screwdriver, hand shear, reverse chain, high stool, rope, pointed punch, nail gun, brush, etc. 2. Process flow of ventilation duct engineering: 1. Production and unfolding of galvanized thin steel pipe air duct ->cutting ->chamfering ->bite production ->duct folding ->forming ->flange cutting ->flange welding ->flange drilling and punching ->riveting and flanging; 2. Installation and transportation of galvanized thin steel pipe and stainless steel pipe, installation of support and hanger, installation of main pipe, installation of vertical pipe, installation of branch pipe, detection of light and air leakage, acceptance of concealed works, anti-corrosion and insulation, single machine commissioning, comprehensive commissioning;

　　3、HDPE雙壁波紋管安裝材料驗收 → 風(fēng)管下料 → 制作 → 焊接 → 加固 → 測試 → 隱蔽工程驗收 → 調(diào)試。

　　3. HDPE double wall corrugated pipe installation material acceptance → duct cutting → fabrication → welding → reinforcement → testing → concealed engineering acceptance → commissioning.

　　3通風(fēng)管道工程操作工藝1、標(biāo)高按設(shè)計要求并參照土建基準(zhǔn)線找出風(fēng)管標(biāo)高。

　　3. Operation process of ventilation duct engineering: 1. Determine the elevation of the air duct according to the design requirements and refer to the civil engineering reference line.

　　2、制作、吊架（1）按照風(fēng)管系統(tǒng)所在的空間位置，確定風(fēng)管的支吊架開式并參照華北標(biāo)辦圖集《通風(fēng)與空調(diào)工程：91SB6》的用料規(guī)格和做法制作。（2）風(fēng)管支、吊架的制作應(yīng)注意的問題：① 支架的懸臂、吊架的吊鐵采用角鋼或槽鋼制成，斜撐的材料為角鋼，吊桿采用圓鋼，扁鐵用來制作抱箍。② 鋼材切斷和打孔，不應(yīng)使用氧氣—乙炔切割。支架的焊縫必須飽滿。③ 吊桿圓鋼應(yīng)根據(jù)風(fēng)管安裝標(biāo)高適當(dāng)截取，兩端套絲不宜過長。④ 支吊架制作完畢后，應(yīng)進(jìn)行除銹和刷防銹漆。（3）吊點(diǎn)的設(shè)置：用膨脹螺栓法：特點(diǎn)是施工靈活、準(zhǔn)確、快速。

　　2. Production and hanger (1) Determine the support and hanger opening of the air duct according to the spatial position of the air duct system, and refer to the material specifications and methods in the North China Standard Atlas "Ventilation and Air Conditioning Engineering: 91SB6" for production. (2) Precautions for the fabrication of air duct supports and hangers: ① The cantilever of the support and the hanging iron of the hanger are made of angle steel or channel steel, the slant support is made of angle steel, the suspender is made of round steel, and the flat iron is used to make hoop. ② Oxygen acetylene cutting should not be used for cutting and punching steel. The weld seam of the bracket must be full The round steel of the suspension rod should be cut appropriately according to the installation elevation of the air duct, and the threading at both ends should not be too long After the production of the support and hanger is completed, rust removal and anti rust paint should be applied. (3) Setting of suspension points: using expansion bolt method: characterized by flexible, accurate, and fast construction.

　　3、安裝吊架（1）按風(fēng)管的中心線，找出吊桿敷設(shè)位置，單吊桿在風(fēng)管中的中心線上，雙吊桿可以按托盤的螺孔間距或風(fēng)管的中心線對稱安裝。（2）吊桿根據(jù)吊件形式，用螺母擰在槽鋼掛件上。（3）當(dāng)風(fēng)管較長時，需要安裝一排支架時，可先把兩端安好，然后以兩端的支架為基準(zhǔn)，用拉線法找出中間支架的標(biāo)高進(jìn)行安裝。（4）立管管卡安裝時，應(yīng)先把最上面的一個管件固定好，再用線錘在中心處吊線，下面的管卡即可按線進(jìn)行固定。（5）支、吊架安裝應(yīng)注意的問題：① 支、吊架的標(biāo)高必須正確，如圓形風(fēng)管管徑由大變小，為保證風(fēng)管中心線水平，支架型鋼上表面標(biāo)高，應(yīng)作相應(yīng)提高。② 風(fēng)管支吊架間距如無設(shè)計要求時，對不保溫風(fēng)管應(yīng)符合表2的要求。對于保溫風(fēng)管、支、吊架間距無設(shè)計要求時，按表2間距要求值乘以0、85。螺旋風(fēng)管的支、吊架間距可以適當(dāng)增加。③ 支吊架不得安裝在風(fēng)口、閥門檢查孔等處，以免妨礙操作,吊架不得直接吊在法蘭上。④ 保溫風(fēng)管不能直接與支吊架接觸，應(yīng)墊上堅固的隔熱材料、其厚度與保溫相同，防止產(chǎn)生"冷橋"。

　　3. Install the hanger (1) according to the centerline of the air duct, find the position for laying the hanger. The single hanger is on the centerline of the air duct, and the double hanger can be symmetrically installed according to the spacing between the screw holes of the tray or the centerline of the air duct. (2) The suspension rod is screwed onto the channel steel hanger with a nut according to the form of the hanger. (3) When the air duct is long and a row of brackets need to be installed, the two ends can be installed first, and then the elevation of the middle bracket can be found using the wire drawing method based on the brackets at both ends for installation. (4) When installing the riser pipe clamp, the topmost pipe fitting should be fixed first, and then a plumb bob should be used to hang the line at the center. The lower pipe clamp can be fixed according to the line. (5) Attention should be paid to the installation of supports and hangers: ① The elevation of supports and hangers must be correct. For example, if the diameter of a circular air duct changes from large to small, in order to ensure that the centerline of the air duct is horizontal, the elevation of the upper surface of the support steel should be correspondingly increased. ② If there are no design requirements for the spacing between air duct supports and hangers, non insulated air ducts should comply with the requirements in Table 2. When there are no design requirements for the spacing between insulated ducts, supports, and hangers, multiply the spacing requirements in Table 2 by 0 and 85. The spacing between the supports and hangers of spiral ducts can be appropriately increased Support hangers shall not be installed at air vents, valve inspection holes, etc. to avoid hindering operation, and hangers shall not be directly hung on flanges Insulated ducts should not be in direct contact with supports and hangers, and should be padded with sturdy insulation material of the same thickness as the insulation to prevent the formation of "cold bridges".

　　4、聚氯乙烯風(fēng)管安裝聚氯乙烯風(fēng)管也與鋼板風(fēng)管一樣采用支、吊托架，但一般以吊架為主，支架間距按要求制作安裝，但需做好以下幾點(diǎn)：（1）當(dāng)支管較長時，則應(yīng)在靠近于管的一端設(shè)置一支架。（2）支架的抱箍制作應(yīng)與風(fēng)管留有一定間隙，便于風(fēng)管伸縮。5、風(fēng)管排列安裝（1）法蘭連接為保證法蘭接口嚴(yán)密性，法蘭之間應(yīng)有墊料。（2）墊料8501密封膠帶使用方法① 將風(fēng)管法蘭表面的異物和積水清理掉，并擦干凈。② 從法蘭一角開始粘貼膠帶，膠帶端頭應(yīng)略長于法蘭。③ 沿法蘭均勻平整地粘貼，并在粘貼過程中用手將其按實，不得脫落，接口處要嚴(yán)密，各部位均不得凸人風(fēng)管內(nèi)，沿法蘭粘貼一周后與起端交叉搭接，剪去多余部分。

　　4. The installation of PVC air ducts also uses support and suspension brackets like steel plate air ducts, but generally relies on hangers. The spacing between brackets should be made and installed according to requirements, but the following points should be taken into account: (1) When the branch pipe is long, a bracket should be set up near the end of the pipe. (2) The clamp of the bracket should be made with a certain gap between it and the air duct to facilitate the expansion and contraction of the air duct. 5. Installation of air duct arrangement (1) Flange connection: To ensure the tightness of the flange interface, there should be padding between the flanges. (2) Instructions for using gasket 8501 sealing tape: ① Clean the foreign objects and accumulated water on the surface of the air duct flange and wipe it clean. ② Starting from one corner of the flange, stick the tape, and the end of the tape should be slightly longer than the flange Paste evenly and smoothly along the flange, and press it firmly by hand during the pasting process without falling off. The interface should be tight, and no part should protrude into the air duct. After pasting along the flange for one week, cross and overlap with the starting end, and cut off the excess part.④ 剝?nèi)ジ綦x紙。（3）法蘭連接法蘭連接時，要求規(guī)定墊料，把兩個法蘭對正，穿螺栓并戴上螺母，(注意：螺母要在同一側(cè))，暫時不要上緊，直到所有螺栓都穿上后，再把螺栓擰緊。連接好風(fēng)管，應(yīng)以兩端法蘭為準(zhǔn)，拉線檢查風(fēng)管連接是否平直。（4）墊法蘭墊料和法蘭連接時，應(yīng)注意的問題：① 正確選用墊料，避免用錯墊料。② 法蘭表面應(yīng)干凈無異物。③ 法蘭墊料不能擠入或凸入管內(nèi)，否則會增大流動阻力，增加管內(nèi)積塵。④ 法蘭連接后，嚴(yán)禁往法蘭縫隙填塞墊料。⑤ 連接法蘭的螺母應(yīng)在同一側(cè)。⑥ 不銹鋼法蘭連接用螺栓，宜用同材質(zhì)不銹鋼螺栓。⑦ 鋁板風(fēng)管法蘭連接應(yīng)采用鍍鋅螺栓，并在法蘭兩側(cè)墊鍍鋅墊圈。⑧ 聚氯乙烯風(fēng)管法蘭和玻璃鋼法蘭連接采用鍍鋅螺栓。（5）風(fēng)管排列無法蘭連接① 抱箍式連接：主要用于鋼板圓風(fēng)管和螺旋風(fēng)管連接，先把每一管段的兩端軋出鼓筋，并使其一端縮為小口。安裝時按氣流方向把小口插入大口，外面用鋼制抱箍將兩個端的鼓箍抱緊連接，最后用螺栓穿在耳環(huán)中間固定擰緊。② 插接式連接：主要用于矩形或圓形風(fēng)管連接。先制作連接管，然后插入兩側(cè)風(fēng)管，再用拉鉚釘將其緊密固定。③ 插條式連接：主要用于矩形風(fēng)管連接。將不同形式的插條插入風(fēng)管兩端，然后壓實。其形狀和接管方法見圖。④ 軟管式連接：主要用于風(fēng)管與部件(如散熱器、靜壓箱側(cè)送風(fēng)口等)的相連。安裝時，軟管兩端套在連接的管外，然后用特別軟卡把軟管箍緊。

　?、?Peel off the isolation paper. (3) When connecting flanges, it is required to specify the padding, align the two flanges, thread the bolts and nuts (note: the nuts should be on the same side), and temporarily do not tighten them until all the bolts are threaded, then tighten the bolts. After connecting the air duct, the flanges at both ends should be used as a reference. Use a wire to check if the air duct connection is straight. (4) When using gasket materials and flange connections, attention should be paid to the following issues: ① Select the gasket materials correctly to avoid using the wrong ones. ② The flange surface should be clean and free of foreign objects The flange gasket should not be squeezed or protruding into the pipe, otherwise it will increase the flow resistance and increase the accumulation of dust inside the pipe After flange connection, it is strictly prohibited to fill the gap of the flange with padding. ⑤ The nuts connecting the flanges should be on the same side Stainless steel flange connection bolts should be made of the same material as stainless steel bolts The flange connection of aluminum plate air ducts should use galvanized bolts, and galvanized washers should be placed on both sides of the flange The connection between PVC duct flange and fiberglass flange adopts galvanized bolts. (5) Air duct arrangement without flange connection ① Clamp type connection: mainly used for connecting steel plate round air ducts and spiral air ducts. First, roll out bulging ribs at both ends of each pipe section and shrink one end into a small mouth. During installation, insert the small opening into the large opening in the direction of the airflow, and use steel clamps to tightly connect the two ends of the drum hoops. Finally, use bolts to secure and tighten them in the middle of the earrings Plug in connection: mainly used for connecting rectangular or circular air ducts. First, make the connecting pipe, then insert the air ducts on both sides, and tightly fix them with rivets Strip connection: mainly used for connecting rectangular ducts. Insert different forms of inserts into both ends of the air duct and compact them. The shape and connection method are shown in the figure. ④ Flexible hose connection: mainly used for connecting air ducts and components (such as radiators, static pressure box side air outlets, etc.). During installation, the two ends of the hose should be placed outside the connected pipe, and then the hose should be tightened with a special soft clamp.

　　6、風(fēng)管安裝就位根據(jù)現(xiàn)場情況，可以在地面連成一片的長度，用吊裝的方法就位，也可以把風(fēng)管一節(jié)一節(jié)地放在支架上，逐節(jié)連接。一般順序是先干管，后支管。立管的安裝一般是由下向上安裝。安裝就位后進(jìn)行找平，找正，達(dá)到設(shè)計規(guī)定的要求。風(fēng)管安裝應(yīng)注意的問題：（1）風(fēng)管采用無法蘭連時，接口處應(yīng)嚴(yán)密、牢固。矩形風(fēng)管四角必須有定位及密封措施。風(fēng)管連接兩平面應(yīng)平直，不得錯位及扭曲。（2）安裝在支架上的圓形風(fēng)管應(yīng)設(shè)托座。（3）風(fēng)管穿出屋面外應(yīng)設(shè)置防雨罩。（4）輸送易產(chǎn)生冷凝水的風(fēng)管，應(yīng)按設(shè)計要求的坡度安裝。風(fēng)管底部不能有縱向接縫，如有接縫應(yīng)用密封處理。（5）鋼板風(fēng)管與磚、混凝土風(fēng)道的插接應(yīng)順應(yīng)氣流方向風(fēng)管與風(fēng)道結(jié)合面必須進(jìn)行密封處理。（6）保溫風(fēng)管的支、吊架宜設(shè)在保溫層外部，并不得損壞保溫層。（7）送風(fēng)管和與總管采用垂直插接時，接口處應(yīng)設(shè)置導(dǎo)風(fēng)調(diào)節(jié)裝置。

　　6. According to the on-site situation, the installation of air ducts can be connected to a length on the ground and placed in place by lifting. Alternatively, the air ducts can be placed section by section on the bracket and connected section by section. The general order is to start with the main pipe and then proceed with the branch pipe. The installation of risers is generally done from bottom to top. After installation, level and align to meet the design requirements. Attention should be paid to the installation of air ducts: (1) When the air duct cannot be connected by flange, the interface should be tight and firm. Rectangular air ducts must have positioning and sealing measures at the four corners. The connection between the two planes of the air duct should be straight, without misalignment or distortion. (2) Circular air ducts installed on brackets should be equipped with brackets. (3) Rainproof cover should be installed when the air duct passes outside the roof. (4) Ducts that are prone to condensation during transportation should be installed at the slope required by the design. There should be no longitudinal seams at the bottom of the air duct. If there are seams, they should be sealed. (5) The connection between steel plate air ducts and brick or concrete air ducts should conform to the direction of airflow. The joint surface between the air duct and the air duct must be sealed. (6) The support and hanger of the insulated air duct should be located outside the insulation layer and should not damage the insulation layer. (7) When the air supply duct and the main pipe are vertically connected, an air guide adjustment device should be installed at the interface.

　　7、風(fēng)管的嚴(yán)密性檢驗風(fēng)管安裝完畢后，應(yīng)按系統(tǒng)壓力等級進(jìn)行嚴(yán)密性檢驗，漏風(fēng)量應(yīng)符合國家規(guī)范《通風(fēng)與空調(diào)工程施工驗收規(guī)范》GB50243—2002中的要求，系統(tǒng)的嚴(yán)密性檢驗應(yīng)符合GB50243-2002規(guī)范附錄A漏光法檢測和漏風(fēng)量測試的規(guī)定。低壓系統(tǒng)的嚴(yán)密性檢驗宜采用抽檢，抽檢率為5％且抽檢不少于一個系統(tǒng)。在加工工藝及漏光檢測不合格時，應(yīng)按規(guī)定的抽檢率做漏風(fēng)量測試。中壓系統(tǒng)的嚴(yán)密性檢驗，應(yīng)在嚴(yán)格的漏光檢測合格條件下，對系統(tǒng)風(fēng)管漏風(fēng)量進(jìn)行抽檢，抽檢率為20％，且抽檢不少于一個系統(tǒng)。高壓系統(tǒng)應(yīng)全數(shù)進(jìn)行漏風(fēng)量測試。系統(tǒng)風(fēng)管漏風(fēng)量測試被抽檢系統(tǒng)應(yīng)全數(shù)合格。如有不合格，應(yīng)加倍抽檢，直至全數(shù)合格。

　　7. After the installation of the air duct is completed, the tightness inspection of the air duct should be carried out according to the system pressure level. The air leakage rate should comply with the requirements of the national standard "Code for Construction Acceptance of Ventilation and Air Conditioning Engineering" GB50243-2002. The tightness inspection of the system should comply with the provisions of Appendix A of GB50243-2002 for light leakage method detection and air leakage rate testing. The tightness inspection of low-voltage systems should be carried out by sampling, with a sampling rate of 5% and no less than one system sampled. When the processing technology and light leakage detection are not qualified, air leakage testing should be conducted according to the prescribed sampling rate. The tightness inspection of the medium voltage system should be carried out under strict light leakage detection conditions, with a sampling rate of 20% for the air leakage of the system ducts, and no less than one system should be sampled. All high-voltage systems should undergo air leakage testing. The system's air duct leakage test should be fully qualified for all sampled systems. If there are any non conformities, double the sampling should be carried out until all are qualified.

　　8、成品保護(hù)（1）安裝完的風(fēng)管要保證表面光滑潔凈，室外風(fēng)管應(yīng)有防雨、防雪措施。（2）風(fēng)管伸入結(jié)構(gòu)風(fēng)道時，其末端應(yīng)安裝上鋼板網(wǎng)，防止系統(tǒng)運(yùn)行時，雜物進(jìn)入金屬風(fēng)管內(nèi)。金屬風(fēng)管與結(jié)構(gòu)風(fēng)道縫隙應(yīng)封堵嚴(yán)密。（3）風(fēng)管穿越沉降縫時應(yīng)按設(shè)計要求加設(shè)套管，套管與風(fēng)管的間隙用填料(軟質(zhì))封堵嚴(yán)密。（4）運(yùn)輸和安裝不銹鋼，鋁板風(fēng)管時，應(yīng)避免產(chǎn)生刮傷表面的現(xiàn)象，安裝時，盡量減少與鐵質(zhì)物品接觸。（5）運(yùn)輸和安裝閥件時，應(yīng)避免由于碰撞而產(chǎn)生的執(zhí)行機(jī)構(gòu)和葉片變形。露天堆放應(yīng)有防雨、防雪措施。

　　8. Finished product protection (1) The installed air duct should ensure a smooth and clean surface, and outdoor air ducts should have rain and snow protection measures. (2) When the air duct extends into the structural air duct, a steel mesh should be installed at its end to prevent debris from entering the metal air duct during system operation. The gaps between metal ducts and structural air ducts should be tightly sealed. (3) When the air duct passes through the settlement joint, a sleeve should be added according to the design requirements, and the gap between the sleeve and the air duct should be tightly sealed with filler (soft). (4) When transporting and installing stainless steel and aluminum plate ducts, the phenomenon of scratching the surface should be avoided, and contact with iron objects should be minimized as much as possible during installation. (5) When transporting and installing valve components, precautions should be taken to avoid deformation of the actuator and blades caused by collisions. Outdoor storage should have measures to prevent rain and snow.

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