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　　根據工藝要求，本機庫項目設計了油箱機械排風系統，將其中的殘油揮發氣體排出室外。排風管經過地面設備（專用地井）中的快速接頭和軟管與油箱相連。排風總管直埋敷設，經過濾后由設置于機庫外的防爆風機高空排放。其排風系統為防爆排風系統，排風機及電機采用防爆型，風管、排風機需采取防靜電接地措施，排風機的進風口、出風口的柔性連接管和風管法蘭兩端應用導線跨接，風管均采用密實焊接、非燃燒材料制作。

　　According to the process requirements, this hangar project has designed a mechanical exhaust system for the fuel tank to discharge the residual oil volatile gases outdoors. The exhaust duct is connected to the fuel tank through a quick connector and hose in the ground equipment (dedicated well). The exhaust duct is directly buried and installed, and after filtration, it is discharged at high altitude by explosion-proof fans installed outside the hangar. The exhaust system is an explosion-proof exhaust system, and the exhaust fan and motor are explosion-proof. Anti static grounding measures need to be taken for the air ducts and exhaust fans. The flexible connecting pipes and flanges at the inlet and outlet of the exhaust fan should be crossed with wires, and the air ducts are made of dense welding and non combustible materials.

　　一、風管加工制作及安裝的要求

　　1、 Requirements for processing, manufacturing, and installation of air ducts

　　油箱通風系統埋地管道采用無縫鋼管，地上架空排風管道采用2.0?mm厚304號不銹鋼板焊接制作，焊接連接。因避免不滿足排放標準的有毒有害氣體泄漏，不銹鋼管道的制作及安裝連接采用氬弧焊。油箱通風系統共18個排風系統，每個排風系統不銹鋼管管道規格為最大直徑500mm，最小300mm×400mm，管道長度共計25m，其中水平管道10m豎直管道15m。

　　The buried pipeline of the fuel tank ventilation system adopts seamless steel pipes, and the overhead exhaust pipeline on the ground adopts 2.0? Welding production and connection of mm thick 304 stainless steel plate. To avoid the leakage of toxic and harmful gases that do not meet emission standards, argon arc welding is used for the production, installation, and connection of stainless steel pipelines. The fuel tank ventilation system has a total of 18 exhaust systems, each with stainless steel pipes with a maximum diameter of 500mm and a minimum diameter of 300mm × 400mm. The total length of the pipes is 25m, including 10m horizontal pipes and 15m vertical pipes.

　　建設單位對風管加工制作及安裝的工期、質量和安全方面的要求十分嚴格。當現場滿足施工條件時，該排風系統立即施工往下進行，以便達到節約施工時間的目的；質量方面采用風管的加工制作及連接都在風管加工廠制作（碰頭連接除外），這樣避免了因場地不平整影響風管連接的垂直度。因每個油箱通風系統排風不銹鋼風管立管都位于室外空曠地帶，設計給出風管置于方形支架內部，方形支架由角鋼焊接制作。并通過槽鋼將不銹鋼風管固定在方形支架內。所以合理選擇304號不銹鋼風管的加工制作及安裝方式，決定了不銹鋼風管能否保障對質量、觀感及進度的要求。

　　The construction unit has very strict requirements for the construction period, quality, and safety of air duct processing, manufacturing, and installation. When the construction conditions are met on site, the exhaust system will immediately proceed to save construction time; In terms of quality, the processing, production, and connection of air ducts are all carried out in the air duct processing factory (except for joint connections), which avoids the impact of uneven site on the verticality of air duct connections. Due to the fact that each fuel tank ventilation system exhaust stainless steel duct riser is located in an outdoor open area, the design proposes that the duct be placed inside a square bracket, which is welded with angle steel. And fix the stainless steel air duct in the square bracket through channel steel. Therefore, the reasonable selection of processing, manufacturing, and installation methods for 304 stainless steel air ducts determines whether the stainless steel air ducts can meet the requirements for quality, appearance, and progress.

　　二、風管加工制作方式的確立及存在的問題

　　2、 The establishment and existing problems of air duct processing and manufacturing methods

　　1.風管加工制作方式的選擇（1）風管加工流水線主要機械設備：裁板機、卷圓機、激光切割機組、氬弧自動焊機床、鉚釘機、氬弧焊機、卷板機、法蘭卷圓機、折板機。每臺設備須配備專業技術操作人員，風管加工制作之前需對技術操作人員進行考核，考核合格后方可持證上崗。（2）風管材料的選擇：由于不銹鋼板材規格為標準尺寸，所以要選擇一種節約材料、加工工藝簡單、風管質量符合要求、觀感性強、安裝方便的板材規格尤為重要。常見的2.0厚304號不銹鋼板卷材規格寬度為1?000?mm、1?219?mm、1?500?mm、1?800?mm。根據這幾種不銹鋼板材的寬度在滿足圖紙要求、施工質量驗收規范和通風管道技術規程的同時，還須考慮風管加工工藝的難易程度、材料的損耗問題、風管安裝的難易程度及工期等因素，綜合以上對比分析得出選用的風管板材為不銹鋼卷材規格寬度1?219?mm最佳。其理由如下。

　　1. Selection of air duct processing and manufacturing methods: (1) The main mechanical equipment of the air duct processing assembly line includes cutting machine, coiling machine, laser cutting unit, argon arc automatic welding machine bed, riveting machine, argon arc welding machine, coiling machine, flange coiling machine, and folding plate machine. Each device must be equipped with professional technical operators. Before the processing and production of air ducts, the technical operators must be assessed and qualified before they can work with certificates. (2) The selection of air duct materials: As the stainless steel plate specifications are standard sizes, it is particularly important to choose a plate specification that saves materials, has simple processing technology, meets the required air duct quality, has strong visual appeal, and is easy to install. What is the width of a common 2.0mm 304 stainless steel plate coil? 000? mm、1? 219? mm、1? 500? mm、1? 800? Mm. Based on the width of these stainless steel plates, while meeting the requirements of the drawings, construction quality acceptance standards, and ventilation duct technical regulations, factors such as the difficulty of the air duct processing technology, material loss, the difficulty of air duct installation, and the construction period must also be considered. Taking into account the above comparative analysis, the selected air duct plate is a stainless steel coil with a specification width of 1 mm? 219? Mm is the best. The reasons are as follows.

　　1）管道預制加工工藝簡單：根據GB?50243—2016《通風與空調施工質量驗收規范》中規定“當中壓、高壓系統風管管段長度大于1?250?mm 時，應采取加固框補強措施”，此處選用的不銹鋼卷材加工制作出的風管長度不超過1219，則不須采取風管加固措施，節省了風管加工制作時間，為現場風管施工安裝的順利開展提供了支持。

　　1) The prefabrication process of pipelines is simple: according to the GB 50243-2016 "Code for Acceptance of Construction Quality of Ventilation and Air Conditioning", "when the length of the air duct section of medium and high pressure systems is greater than 1.250 mm, reinforcement frame reinforcement measures should be taken". If the length of the air duct made by processing stainless steel coil used here does not exceed 1219, no air duct reinforcement measures are required, saving time for air duct processing and production, and providing support for the smooth implementation of on-site air duct construction and installation.

　　2）風管美觀度得到了保障和風管加工制作成本大幅降低：根據JGJ/T?141–2017《通風管道技術》得知“直縫圓形風管的直徑大于或等于800?mm且管段長度大于1?250?mm或總表面積大于4?m?時，可采用法蘭形式加固”。此處不需采取風管加固措施，即不采用法蘭形式加固，使得置于室外機庫的通風管道表面觀感更加平整。讓過往的乘客眼中毫無違和感，在滿足規范要求的同時使風管的美觀度得到了保障。同時每根不銹鋼風管節省了兩支不銹鋼法蘭及其配件，并使得風管減少了兩道焊口，極大程度上降低了材料費用及人工費用，從而導致風管加工制作成本大幅降低。

　　2) The aesthetic appeal of the air duct has been guaranteed and the cost of processing and manufacturing the air duct has been significantly reduced: according to JGJ/T? 141-2017 "Ventilation Duct Technology" learned that "the diameter of a straight seam circular duct is greater than or equal to 800 μ m and the length of the duct section is greater than 1 μ m? 250? Mm or total surface area greater than 4? When m?, flange reinforcement can be used. There is no need to take air duct reinforcement measures here, that is, flange reinforcement is not used, so that the surface of the ventilation duct placed in the outdoor hangar looks smoother. Allowing passing passengers to have no sense of discomfort in their eyes, while meeting regulatory requirements, ensuring the aesthetic appeal of the air ducts. At the same time, each stainless steel air duct saves two stainless steel flanges and their accessories, and reduces two welding joints in the air duct, greatly reducing material and labor costs, resulting in a significant reduction in the processing and manufacturing costs of the air duct.

　　3）材料損耗的降低：該工程選用的風管板材為不銹鋼卷材規格寬度1?219?mm，即把不銹鋼卷材規格寬度1?219?mm側作為風管的長度進行加工，利用裁板機根據風管周長將不銹鋼卷材進行切割，利用卷圓機將裁好的不銹鋼卷材加工成圓形風管，后利用氬弧自動焊機床將不銹鋼圓形風管進行焊接合成。由此可看出極大程度上降低了板材的損耗，這樣不銹鋼板材幾乎零損耗，且每節風管的制作加工裁板機只需切割一次，延長了裁板機及其配件的使用壽命，減少了風管加工制作周期；相應地降低了人工操作機器次數及人工搬運風管次數，節約了人工成本。

　　3) Reduction of material loss: The air duct sheet selected for this project is stainless steel coil with a specification width of 1? 219? mm， Which is the width of the stainless steel coil specification 1? 219? The mm side is processed as the length of the air duct, and the stainless steel coil is cut according to the circumference of the air duct using a cutting machine. The cut stainless steel coil is processed into a circular air duct using a coiling machine, and then the stainless steel circular air duct is welded together using an argon arc automatic welding machine. From this, it can be seen that the loss of the sheet metal has been greatly reduced, resulting in almost zero loss of stainless steel sheet metal. In addition, each section of the air duct only needs to be cut once by the cutting machine, which extends the service life of the cutting machine and its accessories and reduces the processing and production cycle of the air duct; Correspondingly, the number of manual machine operations and manual handling of air ducts has been reduced, saving labor costs.

　　2.風管加工方式的確定設計要求油箱通風系統地上架空排風管道采用2.0?mm厚304號不銹鋼板焊接制作，焊接連接。圓形風管常見的連接方式有兩種：一種法蘭連接、一種無法蘭連接。采用法蘭焊接連接的方式：增加材料304號不銹鋼L30×4法蘭兩支、固定法蘭焊口兩道。果斷放棄此浪費材料費及人工費的不銹鋼風管加工制作方案，確立圓形不銹鋼風管采用無法蘭連接的加工制作方式。首次預制，裁板機從不銹鋼卷材上切割下來不銹鋼板，經卷板機卷成圓管狀的兩節風管，中心對齊后，采用對焊的方式將兩節不銹鋼風管進行連接。出現了下列問題。

　　2. The determination of the processing method for the air duct requires that the above ground overhead exhaust duct of the fuel tank ventilation system adopt 2.0? Welding production and connection of mm thick 304 stainless steel plate. There are two common connection methods for circular air ducts: flange connection and non flange connection. Adopting flange welding connection method: adding two sets of 304 stainless steel L30 × 4 flanges and fixing two flange welds. Resolutely abandon the stainless steel duct processing and manufacturing plan that wastes material and labor costs, and establish a processing and manufacturing method for circular stainless steel ducts that cannot be connected by a flange. For the first prefabrication, the stainless steel plate is cut from the stainless steel coil by a cutting machine, and then rolled into two circular tube shaped air ducts by a coiling machine. After aligning the centers, the two stainless steel air ducts are connected by butt welding. The following issues have occurred.

　　（1）不銹鋼卷材經焊接加熱后出現了應力變形，管道變形嚴重，影響觀感。

　　(1) The stainless steel coil undergoes stress deformation after welding and heating, causing severe deformation of the pipeline and affecting its appearance.

　　（2）不銹鋼風管連接處不平整且有焊瘤、焊渣及飛濺物。對此，直接否定了不銹鋼風管采用對焊的連接方式。經查閱通風與空調施工質量驗收規范得知圓形風管無法蘭連接方式有：承插連接、帶加強筋承插、角鋼加固承插、芯管連接、立筋抱箍連接、抱箍連接、內脹芯管連接。設計要求油箱通風系統地上架空排風管道采用2.0?mm厚304號不銹鋼板焊接制作，焊接連接。而規范里圓形風管無法蘭連接方式沒有焊接連接的方式，經討論決定借鑒圓形風管無法蘭連接中的“立筋抱箍連接”方式。

　　(2) The connection of the stainless steel air duct is uneven and has weld beads, welding slag, and splashes. This directly denies the use of butt welding connection method for stainless steel air ducts. After consulting the construction quality acceptance standards for ventilation and air conditioning, it was found that the flange free connection methods for circular air ducts include socket connection, reinforced bar socket, angle steel reinforced socket, core pipe connection, vertical bar clamp connection, clamp connection, and internal expansion core pipe connection. Design requirement: The above ground overhead exhaust duct of the fuel tank ventilation system should be 2.0? Welding production and connection of mm thick 304 stainless steel plate. However, in the standard, there is no welding connection method for circular air ducts without flanges. After discussion, it was decided to refer to the "vertical reinforcement hoop connection" method in circular air ducts without flanges.

　　3.改進后不銹鋼風管加工制作的方法采用圓形風管無法蘭連接中的“立筋抱箍連接”方式，不銹鋼風管的加工制作方法為：激光切割機組從寬度為1?220?mm的不銹鋼卷材上切割下來長度為1?570?mm的不銹鋼板；經卷板機卷成直徑500?mm的圓管狀風管；利用氬弧自動焊機床將風管不銹鋼板材進行焊接連接；然后折板機將風管兩端進行90°扳邊，扳邊寬度為15?mm。此扳邊寬度為15?mm，由首次預制時兩節風管采用對焊連接得出焊縫周圍15?mm范圍外風管板材不會因焊接受影響得出。該范圍內管道不會因焊接板材受熱應力形變導致的不平整，幾乎不存在焊瘤、焊渣及飛濺物。

　　3. The improved method for processing and manufacturing stainless steel air ducts adopts the "vertical reinforcement hoop connection" method in the flange free connection of circular air ducts. The processing and manufacturing method of stainless steel air ducts is as follows: the laser cutting unit is used to cut from a width of 1? 220? What is the length of 1 cut from mm stainless steel coil? 570? Mm stainless steel plate; Roll the machine into a diameter of 500? Mm round tubular air duct; Use an argon arc automatic welding machine bed to weld and connect the stainless steel plates of the air ducts; Then the folding machine will bend the edges of the air duct at both ends by 90 degrees, with a width of 15 degrees? Mm. The width of this edge is 15? mm， During the initial prefabrication, two sections of air ducts were connected by butt welding, resulting in a circumference of 15 degrees around the weld seam? The air duct sheet outside the mm range will not be affected by welding acceptance. The pipeline within this range will not be uneven due to thermal stress deformation of the welded plate, and there are almost no weld beads, welding slag, or splashes.

　　4.連接風閥、設備軟接、埋地無縫管不銹鋼風管加工制作的方式因風閥及設備軟接等風管部件存在使用周期短、易損壞的問題，所以如果風管部件與風管采用焊接連接的話，以后更換不便。經我方與設計溝通后，設計同意在保證風管嚴密性的前提下風閥及設備軟接等部件與風管的連接的特殊部位可采用法蘭螺栓連接。在風閥及設備軟接加工訂貨前要求這些風管部件的法蘭為304號不銹鋼材質，以便于風管法蘭與這些風管部件的法蘭螺栓連接。

　　4. The method of processing and manufacturing stainless steel air ducts for connecting air valves, equipment soft joints, and buried seamless pipes is inconvenient to replace in the future if the air duct components are welded to the air duct due to the short service life and easy damage of air valve and equipment soft joints and other air duct components. After communication with our design team, it has been agreed that flange bolts can be used to connect special parts of components such as air valves and equipment soft joints to the air duct, while ensuring the tightness of the air duct. Before ordering the air valve and equipment soft joint processing, it is required that the flanges of these air duct components be made of 304 stainless steel material, in order to facilitate the connection of the air duct flanges with the flange bolts of these air duct components.

　　該油箱通風系統埋地管道采用無縫鋼管，地上架空排風管道采用2.0?mm厚304號不銹鋼風管，由于不銹鋼風管與埋地無縫鋼管材質不同，不能直接進行焊接連接，也只能采用螺栓連接法蘭的方案。首先將無縫鋼管焊接上一只碳素鋼法蘭，除銹刷鍍鋅漆做防腐。然后不銹鋼風管連接無縫管側安裝一只鍍鋅法蘭，滿足規范“不銹鋼風管與法蘭鉚接時，應采用不銹鋼鉚釘；法蘭及連接螺栓為碳素鋼時，其表面應采用鍍鉻或鍍鋅等防腐措施”的要求。最后利用螺栓將不銹鋼風管法蘭與無縫鋼管法蘭進行連接。

　　The underground pipeline of the fuel tank ventilation system adopts seamless steel pipes, and the overhead exhaust pipeline on the ground adopts 2.0? Mm thick 304 stainless steel air duct, due to the difference in material between stainless steel air duct and buried seamless steel pipe, cannot be directly welded and can only be connected with bolted flanges. Firstly, weld the seamless steel pipe onto a carbon steel flange, remove rust, and apply galvanized paint for corrosion prevention. Then install a galvanized flange on the seamless side of the stainless steel air duct connection, meeting the requirements of the specification that "stainless steel rivets should be used when riveting stainless steel air ducts and flanges; when the flange and connecting bolts are made of carbon steel, anti-corrosion measures such as chrome plating or galvanizing should be used on their surfaces". Finally, use bolts to connect the stainless steel duct flange with the seamless steel pipe flange.

　　三、不銹鋼風管制作新工藝——“扳邊”的優缺點經現場采用新工藝給不銹鋼風管扳邊制作后發現，不銹鋼風管扳邊加工制作的優勢遠遠大于常規不銹鋼的加工制作方式。其優缺點對比如下：

　　3、 The advantages and disadvantages of the new process of stainless steel duct production - "edge bending". After adopting the new process on site, it was found that the advantages of stainless steel duct edge bending processing are far greater than those of conventional stainless steel processing methods. The comparison of its advantages and disadvantages is as follows:

　　1.不銹鋼風管扳邊的優點

　　1. Advantages of stainless steel duct flange

　　（1）加工工藝簡單。制作普通圓形鍍鋅風管常常在固定角鋼法蘭后需對風管端面進行扳邊，所以使用機器對風管端面扳邊并不是新工藝，工人對此項技術比較容易掌握，只需熟練的掌握機器操作即可。（2）加工制作成本低。如不采用不銹鋼風管扳邊工藝，在滿足觀感要求及管道強度的同時，只能采用角鋼法蘭不銹鋼風管。扳邊風管相較角鋼法蘭不銹鋼風管而言，每節風管節約了兩支不銹鋼法蘭及其配件，材料成本降低了20%；因為不銹鋼風管要求焊接制作，此工藝節約了焊口兩道，隨之減少了不銹鋼焊條的使用，節省了氬弧自動焊機床的機械費和降低了人工費用。（3）在保障風管質量的同時觀感得到了很大提升。風管增加15?mm扳邊后，該連接位置凸出了風管原材，焊接起來非常方便。且風管焊縫該范圍內不會出現因焊接板材受熱應力形變導致的不平整，幾乎不存在焊瘤、焊渣及飛濺物。使得置于室外機庫的通風管道表面觀感更加平整，讓過往的乘客眼中毫無違和感，大幅提升了觀感度。

　　(1) The processing technology is simple. Making ordinary circular galvanized air ducts often requires trimming the end face of the duct after fixing the angle steel flange, so using a machine to edge the end face of the duct is not a new process. Workers can easily master this technique by proficiently operating the machine. (2) Low processing and manufacturing costs. If the stainless steel air duct trimming process is not used, only angle steel flange stainless steel air ducts can be used while meeting the visual requirements and pipeline strength. Compared to angle steel flange stainless steel air ducts, bent edge air ducts save two stainless steel flanges and their accessories per section, reducing material costs by 20%; Because stainless steel ducts require welding production, this process saves two welding joints, reduces the use of stainless steel welding rods, saves the mechanical cost of argon arc automatic welding machine beds, and reduces labor costs. (3) The appearance has been greatly improved while ensuring the quality of the air ducts. An increase of 15 air ducts? After the mm edge is bent, the connection position protrudes from the raw material of the air duct, making welding very convenient. And there will be no unevenness caused by thermal stress deformation of the welded plate within this range of the air duct weld, and there are almost no weld beads, welding slag, or splashes. This makes the surface of the ventilation ducts placed in the outdoor hangar appear smoother, leaving no sense of discomfort in the eyes of passing passengers and greatly enhancing the visual appeal.

　　2.不銹鋼風管扳邊的缺點

　　2. Disadvantages of stainless steel duct flange

　　（1）造成不銹鋼板材材料增加。因不銹鋼風管兩端端面分別扳邊15?mm，導致1?219?mm寬度的不銹鋼卷材制成的風管長度為1?189?mm。每節風管不銹鋼鋼板材使用量增加2.4%。（2）降低了不銹鋼風管強度。不銹鋼風管端面扳邊，扳邊縫由于扭矩的原因，降低了風管強度，增加了風管撕裂風險。但經檢測機構檢測仍滿足規范對風管強度的要求。（3）人工費的增加。不銹鋼風管端面扳邊需人工操作機器進行，增加了人工使用，造成了降效。

　　(1) Causing an increase in stainless steel sheet material. Because the two end faces of the stainless steel air duct are bent by 15 degrees respectively? mm， Causing 1? 219? What is the length of an air duct made of stainless steel coil with a width of mm? 189? Mm. The usage of stainless steel plates for each section of the air duct has increased by 2.4%. (2) Reduced the strength of stainless steel air ducts. The end face of the stainless steel air duct is bent, and the bending seam reduces the strength of the air duct and increases the risk of duct tearing due to torque. But after testing by the testing agency, it still meets the requirements of the standard for the strength of the air duct. (3) The increase in labor costs. The edge of stainless steel air ducts needs to be manually operated by machines, which increases the use of manual labor and results in reduced efficiency.

　　四、結語

　　4、 Conclusion

　　通過此機庫排風系統不銹鋼管道的施工，圓形不銹鋼風管采取扳邊加工制作工藝取得了重大技術性突破。在滿足不銹鋼風管的功能性與觀感度的同時，相較于傳統不銹鋼風管的加工制作安裝工藝，材料成本降低了約20%，人工費降低了約33%。且大幅縮短了圓形不銹鋼風管的加工制作和安裝周期，尤其在工期緊張的工程中優勢明顯。這種圓形不銹鋼風管的加工制作新工藝值得在工程中借鑒和推廣。

　　Through the construction of stainless steel pipes for the exhaust system of this hangar, a significant technological breakthrough has been achieved in the production of circular stainless steel ducts using the edge bending processing technology. While meeting the functionality and visual appeal of stainless steel ducts, the material cost has been reduced by about 20% and the labor cost has been reduced by about 33% compared to the traditional processing, manufacturing, and installation process of stainless steel ducts. And it significantly shortens the processing, manufacturing, and installation cycle of circular stainless steel air ducts, especially in projects with tight schedules, with obvious advantages. The new process of processing and manufacturing circular stainless steel ducts is worth learning from and promoting in engineering.

　　本文由  山東通風管道 友情奉獻.更多有關的知識請點擊  http://www.jnhxtcg.com/   真誠的態度.為您提供為全面的服務.更多有關的知識我們將會陸續向大家奉獻.敬請期待.

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