WO2009115050A1 - 平面焊接法兰预变形结构 - Google Patents

平面焊接法兰预变形结构 Download PDF

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Publication number
WO2009115050A1
WO2009115050A1 PCT/CN2009/070901 CN2009070901W WO2009115050A1 WO 2009115050 A1 WO2009115050 A1 WO 2009115050A1 CN 2009070901 W CN2009070901 W CN 2009070901W WO 2009115050 A1 WO2009115050 A1 WO 2009115050A1
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Prior art keywords
flange
welded
deformed
welding
front side
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PCT/CN2009/070901
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English (en)
French (fr)
Inventor
戴刚平
王淑红
张国勋
张再新
包镇回
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浙江盛达铁塔有限公司
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Publication of WO2009115050A1 publication Critical patent/WO2009115050A1/zh

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K31/00—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups
    • B23K31/12—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups relating to investigating the properties, e.g. the weldability, of materials
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K31/00—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups
    • B23K31/003—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups relating to controlling of welding distortion
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K31/00—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups
    • B23K31/02—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups relating to soldering or welding
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L23/00—Flanged joints
    • F16L23/02—Flanged joints the flanges being connected by members tensioned axially
    • F16L23/024—Flanged joints the flanges being connected by members tensioned axially characterised by how the flanges are joined to, or form an extension of, the pipes
    • F16L23/026—Flanged joints the flanges being connected by members tensioned axially characterised by how the flanges are joined to, or form an extension of, the pipes by welding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K2101/00—Articles made by soldering, welding or cutting
    • B23K2101/04—Tubular or hollow articles
    • B23K2101/06—Tubes

Definitions

  • This invention relates to planar flange welding techniques, and more particularly to a planar welded flange structure. Background technique
  • Plane welded flanges are widely used in pressure pipes, long-distance pipelines, process pipelines, steel pipe box steel beams and other joint structures in steel structure engineering. They are connected to steel pipes and other structures by welding, and welded flanges will inevitably be produced. Deformation after welding, these deformations will lead to uneven surface of the flange, resulting in air leakage, water leakage, oil leakage, the local bolt strength is significantly reduced, causing the joint to break, resulting in structural damage and other quality accidents. The larger the diameter of the pipe, the greater the deformation, and the thinner the flange, the greater the deformation. In particular, the deformation of the large-diameter flat welded flange increases linearly, causing the gap at the edge of the contact surface to exceed the standard, thus failing to meet the design and specification requirements.
  • the present invention provides a flat welded flange pre-deformation structure which reduces cost and reduces labor intensity.
  • a pre-deformed structure of a planar welded flange comprising a flange and a steel pipe, the end of the steel pipe being welded to the flange, and the geometric center of the cross section of the flange near the welded portion is away from the steel pipe before welding Offset, the portion where the offset occurs constitutes the pre-deformed segment.
  • the pre-deformed section has a slope shape.
  • the pre-deformed segments can also be other shapes, such as curves.
  • the flange is a double-ring flange, and bolt holes are arranged on the flanges on both sides of the welded portion, and pre-deformed sections are provided on the flanges on both sides of the welded portion.
  • the flange includes a front side and a back side, the front side is in contact with the steel pipe, and the front side or the back side is provided with a pre-deformed section.
  • the flange is a single-ring flange, and a bolt hole is provided on the outer flange of the weld, and a pre-deformation section is provided on the outer flange of the weld.
  • the flange includes a front side and a back side, the front side being in contact with the steel tube, and the back side is provided with a pre-deformed section.
  • the technical idea of the present invention is: the design of the flange surface, according to the thickness and size of the flange, the welding method, the welding procedure, the welding process parameters, etc., the size of the design is adjusted multiple times, and the surface shape opposite to the welding deformation .
  • This shape is copied to the flat flange to be welded so that the product reserves the amount of deformation that will occur, and the pre-deformed imitation is used to offset the welding deformation, so that the welding is completed once, without the use of prefabricated formwork and high-strength bolt fixing.
  • the facility or heating is used to eliminate distortion.
  • the beneficial effects of the invention are mainly manifested in: (1) reducing cost and reducing labor intensity; (2) not using a liner, reducing manufacturing cost, increasing the joint surface of the flange plane, increasing the stability of the structure, and making the joint Reliable, safe to operate; (3), without flange preset template, to increase the rigidity of the fixed flange, so as not to deform, reduce the residual stress after welding, eliminate the large number of additional templates brought by this process , the waste caused by the use of high-strength bolts, while reducing the manufacturing cycle; (4), improve the environment and labor intensity of construction operations, do not use post-weld heating to reduce the welding deformation of the flange, and at the same time prevent the heating caused by oxygen-acetylene
  • the over-temperature causes serious consequences of changes in the structural properties of the joint; (5) increases the joint surface of the flange, increases the overall stability, ensures safe operation of the product, and ultimately deforms The size is controlled within 0.4mm to meet this extremely high quality requirement.
  • Figure 1 is a schematic view of the double-ring hole flange processing.
  • Figure 2 is a cross-sectional view of Figure 1.
  • Figure 3 is a partial enlarged view of the double-ring hole flange processing.
  • Figure 4 is a schematic view of the processing of a single-turn hole flange.
  • Figure 5 is a cross-sectional view of a single-turn hole flange process.
  • a planar welded flange pre-deformation structure includes a flange 1 and a steel pipe 2, and the end of the steel pipe 2 is welded to the flange 1, and the flange 1 is adjacent to the welded portion before welding.
  • the geometric center of the cross section of the portion is offset away from the steel tube 2, and the offset portion constitutes the pre-deformed section 3.
  • the pre-deformed section 3 has a slope shape.
  • the pre-deformed segments can also be other shapes, such as curves and the like.
  • the flange 1 is a double-ring hole flange, and bolts are provided on the flanges on both sides of the welded portion, and pre-deformed sections are provided on the flanges on both sides of the welded portion.
  • the flange 1 includes a front side and a back side, the front side is in contact with a steel pipe, and the front side or the back side is provided with a pre-deformed section.
  • the shape of the pre-deformed section 3 of this embodiment is identical to the surface shape opposite to the welding deformation. This shape, which is replicated onto the flat flange to be welded, allows the product to retain the amount of deformation that will occur, achieving a pre-deformed imitation to counteract the weld distortion.
  • This embodiment has been successively in the 500kV Hanglan Line Large Crossing Tower, 500kV Qianjiang-Xianning Yangtze River Great Crossing Tower, Nanjing Sanjiangkou Big Crossing Tower, Yellow River Great Crossing Tower, 220kV Zhoushan Networking Great Crossing Tower, 500kV Tainan
  • the construction of the variable structure bracket and the 500kV Wendong allogenic bracket is carried out in accordance with the design and specification requirements.
  • the flange 1 of the present embodiment is a single-ring hole flange, and a bolt hole is provided on the outer flange of the welded portion, and a pre-deformed portion is provided on the outer flange of the welded portion.
  • the flange includes a front side and a back side, the front side is in contact with the steel tube, and the back side is provided with a pre-deformed section.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Flanged Joints, Insulating Joints, And Other Joints (AREA)
  • Butt Welding And Welding Of Specific Article (AREA)

Description

说 明 书
平面焊接法兰预变形结构 技术领域
本发明涉及平面法兰焊接技术， 尤其是一种平面焊接法兰结构。 背景技术
平面焊接法兰广泛应用于压力管道、长输管道、工艺管道、钢结构 工程中的钢管箱体钢梁等连接结构， 通过焊接与钢管等结构相连， 而 焊接式法兰总会不可避免地产生焊后变形， 这些变形会导致法兰表面 不平整， 造成漏气、漏水、漏油， 局部螺栓强度明显下降， 使之连接部 位发生断裂， 造成结构早期破坏等质量事故。 管道直径越大， 变形就 越大， 法兰越薄， 变形也越大。 特别是大直径平面焊接法兰的变形呈 线性增大， 造成接触面边缘间隙超标， 从而不能满足设计及规范要求。
目前国内外制造业常用防止变形的方法是：
( 1 ) 、依靠不同材料的柔性连接： 如在法兰的内圈加各种衬垫， 包括铜、 钛等合金制成的衬垫， 抵消焊接变形所产生的间隙， 这种方 法使用的最为普通， 从而使造价大幅度提高， 这类衬垫在使用过程中 还需经常更换， 使之维修成本再次增加。 由于这种加衬垫的方法使间 隙带有柔性， 工件精度降低， 一般不能应用于高温高压管道和承重钢 结构。
(2 ) 、增加法兰面的刚性： 先制造一个与此法兰相同大小， 厚度 较厚的模板， 把这个模板与法兰通过高强螺栓相连接， 间接增加法兰 厚度， 增加法兰的导热性， 提高法兰的刚性， 即提高法兰抵抗焊接变 形的能力来控制变形。 这一方法得预先制造多个刚性固定用法兰， 然 后用高强螺栓连接， 焊接冷却后拆除， 多花材料及人工， 造成大量浪 费及损坏法兰背部的光洁度。
(3 ) 、 采用焊后加热的方法： 用氧-乙炔火焰加热变形区， 使之 因焊接应力产生的变形区屈服， 冷却后使焊接变形减少和消除的方法。 这一方法虽然有用但付出大量的人力和消耗大量的氧气、 乙炔气， 特 别对大型厚法兰的多点作业极为不方便， 使操作人员的工作环境和劳 动强度带来较大的不利， 并对环境产生一定的影响。另外， 采用氧-乙 炔加热的方法对有色金属， 包括不锈钢、铝、镁合金更为不利， 对合金 高强度结构钢加热温度如控制不当还将带来接头的组织变化， 造成强 度下降， 甚至在运行中产生裂缝。
以上三种方法虽然都是常用的， 但存在耗费钢材、人力、物力、时 间和增加劳动强度的缺点。
发明内容
为了克服已有平面法兰焊接结构的成本高、增加劳动强度的不足， 本发明提供一种降低成本、减轻劳动强度的平面焊接法兰预变形结构。
本发明解决其技术问题所采用的技术方案是：
一种平面焊接法兰预变形结构， 包括法兰和钢管， 所述钢管的端 部与法兰焊接， 在焊接前， 所述法兰靠近焊接处的部分的横截面的几 何中心向远离钢管方向偏移， 发生偏移的部分构成预变形段。
作为优选的一种方案： 所述预变形段呈斜坡状。 当然的， 预变形 段也可以为其他形状， 例如曲线等。
作为优选的另一种方案： 所述法兰为双圈孔法兰， 在所述焊接处 的两侧的法兰上设有螺栓孔， 在焊接处的两侧的法兰上均设有预变形 段。 进一步， 所述法兰包括正面和背面， 所述正面与钢管接触， 所述 正面或背面设有预变形段。
作为优选的再另一种方案： 所述法兰为单圈孔法兰， 在所述焊接 处的外侧的法兰上设有螺栓孔， 在焊接处的外侧的法兰上设有预变形 段。
再进一步， 所述法兰包括正面和背面， 所述正面与钢管接触， 所 述背面设有预变形段。
本发明的技术构思为： 过对法兰面的设计， 根据法兰的厚度、 大 小不同， 焊接方法、焊接程序、焊接工艺参数不同等， 多次调整设计的 尺寸， 与焊接变形相反的表面形状。 这一形状， 被复制到待焊接的平 面法兰上使产品预留了将要出现的变形量， 达到预变形的仿制来抵消 焊接变形， 使焊接一次完成， 不必使用预制模板加高强螺栓固定等辅 助设施或采用加热来消除变形。
消除焊接变形对法兰平整度的影响， 使两法兰贴合面间隙满足国 标 GB50205-2001 《钢结构工程施工质量验收规范》 要求。
本发明的有益效果主要表现在： （1 ) 、降低成本、减轻劳动强度; (2 ) 、不采用衬垫， 降低制造成本， 增加法兰平面的结合面， 达到增 加结构的稳定性， 使联接可靠， 运行安全； （3 ) 、不采用法兰预置模 板， 来增加刚性固定法兰， 使之不变形的方法， 减少焊后的残余应力， 消除采用这一工艺带来的大量额外的模板、 高强螺栓使用所造成的浪 费， 同时减少制造周期； （4) 、改善施工作业的环境及劳动强度， 不 采用焊后加热的办法来减少法兰的焊接变形， 同时杜绝由于氧 -乙炔 加热引起的超温使接头组织性能发生变化带来的严重后果； （5 ) 、使 法兰平面接合面增大， 总体稳定增加， 确保产品安全运行， 最终变形 尺寸控制在 0.4mm以内， 满足这一极高的质量要求。
附图说明
图 1是双圈孔法兰加工示意图。
图 2是图 1的截面图。
图 3是双圈孔法兰加工的局部放大图。
图 4是单圈孔法兰加工示意图。
图 5是一种单圈孔法兰加工的截面图。
具体实施方式
下面结合附图对本发明作进一步描述。
实施例 1
参照图 1〜图 3， 一种平面焊接法兰预变形结构， 包括法兰 1和 钢管 2， 所述钢管 2的端部与法兰 1焊接， 在焊接前， 所述法兰 1靠 近焊接处的部分的横截面的几何中心向远离钢管 2方向偏移， 发生偏 移的部分构成预变形段 3。
所述预变形段 3呈斜坡状。 当然的， 预变形段也可以为其他形状， 例如曲线等。
所述法兰 1为双圈孔法兰， 在所述焊接处的两侧的法兰上设有螺 栓孔， 在焊接处的两侧的法兰上均设有预变形段。 所述法兰 1包括正 面和背面， 所述正面与钢管接触， 所述正面或背面设有预变形段。
本实施例的预变形段 3的形状与焊接变形相反的表面形状一致。 这一形状， 被复制到待焊接的平面法兰上使产品预留了将要出现的变 形量， 达到预变形的仿制来抵消焊接变形。
本实施例的焊接结构中， 顶紧接触面有 85%以上的面积紧贴， 满足国标 GB50205-2001《钢结构工程施工质量验收规范》 8.3.3条要求。 2、 用 0.3mm塞尺检査， 其塞入面积小于应 25%, 两法兰贴合面间隙 小于 0.8mm， 满足国标 GB50205-2001《钢结构工程施工质量验收规范 8.3.3条要求。
本实施例已先后在 500kV杭兰线大跨越高塔、 500kV潜江-咸宁长 江大跨越高塔、南京三江口大跨越高塔、黄河大跨越高塔、 220kV舟山 联网大跨越高塔、 500kV台南变构支架、 500kV温东变构支架等工程实 施， 质量符合设计和规范要求。
实施例 2
参照图 4、图 5， 本实施例的法兰 1为单圈孔法兰， 在所述焊接处 的外侧的法兰上设有螺栓孔， 在焊接处的外侧的法兰上设有预变形段。
所述法兰包括正面和背面， 所述正面与钢管接触， 所述背面设有 预变形段。
本实施例的其余结构和工作过程与实施例 1相同。

Claims

权 利 要 求 书
1、一种平面焊接法兰预变形结构， 包括法兰和钢管， 所述钢管的端部 与法兰焊接， 其特征在于： 在焊接前， 所述法兰靠近焊接处的部分的 横截面的几何中心向远离钢管方向偏移， 发生偏移的部分构成预变形 段。
2、如权利要求 1所述的平面焊接法兰预变形结构， 其特征在于： 所述 预变形段呈斜坡状。
3、如权利要求 1或 2所述的平面焊接法兰预变形结构， 其特征在于： 所述法兰为双圈孔法兰， 在所述焊接处的两侧的法兰上设有螺栓孔， 在焊接处的两侧的法兰上均设有预变形段。
4、如权利要求 3所述的平面焊接法兰预变形结构， 其特征在于： 所述 法兰包括正面和背面， 所述正面与钢管接触， 所述正面或背面设有预 变形段。
5、如权利要求 1或 2所述的平面焊接法兰预变形结构， 其特征在于： 所述法兰为单圈孔法兰， 在所述焊接处的外侧的法兰上设有螺栓孔， 在焊接处的外侧的法兰上设有预变形段。
6、如权利要求 4所述的平面焊接法兰预变形结构， 其特征在于： 所述 法兰包括正面和背面， 所述正面与钢管接触， 所述背面设有预变形段。
PCT/CN2009/070901 2008-03-20 2009-03-20 平面焊接法兰预变形结构 WO2009115050A1 (zh)

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CN101251211A (zh) * 2008-03-20 2008-08-27 浙江盛达铁塔有限公司 平面焊接法兰预变形结构
CN102319942A (zh) * 2011-09-05 2012-01-18 沈阳黎明航空发动机(集团)有限责任公司 一种钛合金焊接机匣安装边预变形焊接及微量成形方法
CN105108369A (zh) * 2015-09-14 2015-12-02 无锡市创新化工设备有限公司 一种防法兰焊接变形的结构及焊接方法
DE102015223874A1 (de) 2015-12-01 2017-06-01 Minimax Gmbh & Co. Kg Verfahren zum Herstellen eines Flanschrohlings und eines Flansches
CN106346156B (zh) * 2016-10-26 2018-08-07 杨才军 控制凝汽器水室制造中变形的方法
CN106984919A (zh) * 2017-03-06 2017-07-28 无锡威孚力达催化净化器有限责任公司 运用预变形法控制法兰平面度的加工方法
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