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1、竖向钢筋电渣压力焊质量控制初探A Research on Quality control of Vertical Reinforced bar Electroslag pressure welding杨 青Yang Qing （南平市建设工程质量监督站 353000）提 要本文阐明了竖向钢筋电渣压力焊在工程中广泛应用后产生的质量缺陷的原因及分析和如何解决这些缺陷的措施。关键词竖向钢筋电渣压力焊 质量缺陷 质量控制Abstract: The reasons and analysis of quality defects from popular application of vertical r
2、einforccd bar electroslag pressure welding in engineering and solving methods.Keywords: Vertical reinforccd bar electroslag pressure welding, Quality defects, Quality control.钢筋电渣压力焊是近几年推广、应用较广的竖向钢筋连接技术之一。电渣焊具有节能、节约钢材，经济效益明显，施工操作简便，安全可靠的特点。然而电渣压力焊在实际施工中存在着较多的质量问题，我在钢筋电渣压力焊的施工监督过程中，对焊接质量存在问题进行专题探讨，针对
3、不同问题采取相应措施，有效地控制电渣压力焊焊接质量，确保主体结构的安全、可靠。现将竖向钢筋电渣压力焊易发生的缺陷和质量控制措施分析如下：1 竖向钢筋电渣压力焊易发生的质量缺陷及原因分析（1） 焊接接头弯折原因：刚买来的钢筋或用断料机切割过的钢筋，它的端头不平整，端部产生弯折，这样两根钢筋对接时，接触面就不平从而产生弯折；班组考虑经济因素，使用已经磨损的夹具；班组为了赶工期或夹具数量不够，使得夹具拆除时间太早。（2） 焊接接头轴线位移原因：焊接时上下两钢筋没有处在同一轴线上，接头轴线发生偏移的现象较多。有些工程为了减少焊接接头，柱筋二层一焊接，焊接钢筋长度达6米多，夹具夹紧后，由于钢筋偏长摇晃而
4、造成钢筋轴线的偏移；有的上下夹具没调整好，使上下两钢筋安装不同心；有的端头不直，钢筋虽然保持在同一线上，但端部产生偏移。（3）焊包不均、偏向原因：由于钢筋端面不平；焊剂装不匀或泄漏；回收的焊剂中的杂物没清除干净；钢筋安装时轴线偏移；钢筋端头焊接面不平钢筋熔化后流向低的一面。（4）焊接接头表面气孔、未焊合外观检查时可看见焊包的表面上有气孔，钢筋的端面上有一部分未熔化，切割该根钢筋焊接接头做试验时往往尚未达到屈服强度就断裂。原因：由于焊接电流偏小；焊接时间不足；焊剂受潮等。（5）焊接接头“虚焊”焊接接头结合不良是钢筋电渣压力焊最大质量隐患，结合不良的“虚焊”就是外观正常，但若受外力冲击，接头就会断
5、裂，如果没认真的进行检查将给工程留下隐患。原因：熔透时间不足；电流太小；焊接速度太快；接头面不洁。（6）焊接接头脆断焊接接头外观检查合格，但抽取现场焊接接头做试验时，发现接头脆断。原因：接头降温太快。2 竖向钢筋电渣压力焊质量控制的措施（1） 选择合格的施工班组从事电渣压力焊的焊工在签订合同之前，除了本人持有专业培训取得成绩的合格证外，尚应在施工现场将所焊接钢筋的规格、级别进行焊接后，按JGJ18-2003钢筋焊接及验收规程，进行检查合格后才能签订合同。（2）选择合格的焊剂焊剂在购买时应有出厂合格证，了解该品种焊剂的使用说明，并且将焊剂合格证收集后编号存档，作为焊接的质量保证资料之一。电渣压力
6、焊所使用的焊剂必须干燥，这样才能充分发挥焊剂的物理及化学性能。焊剂使用前须经250300恒温烘烤2小时，施工中尚未烧结成块的焊剂可与新焊剂混合使用但应清除焊剂中杂质，洒落地面上的焊剂极易受潮回收使用时也应该烘烤，严禁使用未烘干的焊剂或出厂时间较久的焊剂。（3） 防止弯折的措施钢筋端头弯折应矫直，使钢筋端头顺直，端头矫直时不能用铁锤敲打；更换已磨损的夹具，夹具安装时应使上下钢筋夹紧，保持两端钢筋的同心度；焊接至少等3min后再拆除夹具，最好多备用一些夹具可提高工效，又可保证焊接质量。（4） 防止轴线位移的措施安装时钢筋端部要顺直，上下夹具调整好并夹紧，使钢筋保持在同一轴线上；焊接长度较长的钢筋应
7、搭设架子，辅助工站在架子上，戴绝缘手套扶持钢筋，使钢筋尽量保持垂直。（5） 防止焊包不均、偏包的措施钢筋端头焊接面应平整，不平的焊接面用切割机切割掉；回收的焊剂中的杂物应清除干净，特别是泥块，且焊剂要干燥，焊剂装填应四周均匀一致，不得泄漏；钢筋应扶持垂直于地面，不能摇晃。（6） 防止气孔未焊合措施所使用的焊剂应烘干；钢筋端头的铁锈用钢丝刷消除干净，同时延长焊接的时间；增大焊接电流；掌握好挤压时间参数。（7） 防止结合不良“虚焊”现象增大电流；避免焊接时间过短；钢筋表面上的水泥浆、污泥、油污及铁锈必须清除干净。（8）防止焊接接头脆断措施禁止在雨天焊接；养护楼板砼的水不要浇到刚焊接完毕的钢筋接头上
8、。（9） 选择合适焊接参数应根据焊接钢筋直径选择适合电渣压力焊电源性能指标，同时掌握电弧过程和电流过程的延续时间。应该说焊接总时间与被焊接钢筋直径密切相关，只有选择适合的焊接参数，才能保证焊接的质量。（10）按规范切取试件施工中应严格执行钢筋焊接及验收规程的具体规定，电渣压力焊接头外观必须分批检查，外观检查要求采取过“三关”的检查制度，即班组自检、工地质检员复检、监理人员重检，确保焊接接头外观质量合格，若外观检查不合格的必须将焊接接头切除重焊。外观检查合格的钢筋接头按规定进行“见证”取样送检。3 结束语竖向钢筋电渣压力焊是一种质量可靠的焊接技术，只要采取有效的质量控制措施，焊接质量完全可以控制
9、，对于工程的使用是安全可靠，完全能满足设计规范和施工验收规范的要求，经济效益明显，特别是目前钢材价格上涨，从而受到施工单位的欢迎和进一步的广泛使用。参 考 文 献1 钢筋焊接及验收规程S， 20032 廖代广主编, 建筑施工技术M， 武汉工业大学出版社，20013 高琼英主编, 建筑材料M， 武汉理工大学出版社，2002Editors note: Judson Jones is a meteorologist, journalist and photographer. He has freelanced with CNN for four years, covering severe weat
10、her from tornadoes to typhoons. Follow him on Twitter: jnjonesjr (CNN) - I will always wonder what it was like to huddle around a shortwave radio and through the crackling static from space hear the faint beeps of the worlds first satellite - Sputnik. I also missed watching Neil Armstrong step foot
11、on the moon and the first space shuttle take off for the stars. Those events were way before my time.As a kid, I was fascinated with what goes on in the sky, and when NASA pulled the plug on the shuttle program I was heartbroken. Yet the privatized space race has renewed my childhood dreams to reach
12、 for the stars.As a meteorologist, Ive still seen many important weather and space events, but right now, if you were sitting next to me, youd hear my foot tapping rapidly under my desk. Im anxious for the next one: a space capsule hanging from a crane in the New Mexico desert.Its like the set for a
13、 George Lucas movie floating to the edge of space.You and I will have the chance to watch a man take a leap into an unimaginable free fall from the edge of space - live.The (lack of) air up there Watch man jump from 96,000 feet Tuesday, I sat at work glued to the live stream of the Red Bull Stratos
14、Mission. I watched the balloons positioned at different altitudes in the sky to test the winds, knowing that if they would just line up in a vertical straight line we would be go for launch.I feel this mission was created for me because I am also a journalist and a photographer, but above all I live
15、 for taking a leap of faith - the feeling of pushing the envelope into uncharted territory.The guy who is going to do this, Felix Baumgartner, must have that same feeling, at a level I will never reach. However, it did not stop me from feeling his pain when a gust of swirling wind kicked up and twis
16、ted the partially filled balloon that would take him to the upper end of our atmosphere. As soon as the 40-acre balloon, with skin no thicker than a dry cleaning bag, scraped the ground I knew it was over.How claustrophobia almost grounded supersonic skydiverWith each twist, you could see the wrinkl
17、es of disappointment on the face of the current record holder and capcom (capsule communications), Col. Joe Kittinger. He hung his head low in mission control as he told Baumgartner the disappointing news: Mission aborted.The supersonic descent could happen as early as Sunday.The weather plays an im
18、portant role in this mission. Starting at the ground, conditions have to be very calm - winds less than 2 mph, with no precipitation or humidity and limited cloud cover. The balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our day-to-day wea
19、ther lives. It will climb higher than the tip of Mount Everest (5.5 miles/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 kilometers) and into the stratosphere. As he crosses the boundary layer (called the tropopause), he can expect a lot of
20、turbulence.The balloon will slowly drift to the edge of space at 120,000 feet (22.7 miles/36.53 kilometers). Here, Fearless Felix will unclip. He will roll back the door.Then, I would assume, he will slowly step out onto something resembling an Olympic diving platform.Below, the Earth becomes the co
21、ncrete bottom of a swimming pool that he wants to land on, but not too hard. Still, hell be traveling fast, so despite the distance, it will not be like diving into the deep end of a pool. It will be like he is diving into the shallow end.Skydiver preps for the big jumpWhen he jumps, he is expected
22、to reach the speed of sound - 690 mph (1,110 kph) - in less than 40 seconds. Like hitting the top of the water, he will begin to slow as he approaches the more dense air closer to Earth. But this will not be enough to stop him completely.If he goes too fast or spins out of control, he has a stabiliz
23、ation parachute that can be deployed to slow him down. His team hopes its not needed. Instead, he plans to deploy his 270-square-foot (25-square-meter) main chute at an altitude of around 5,000 feet (1,524 meters).In order to deploy this chute successfully, he will have to slow to 172 mph (277 kph).
24、 He will have a reserve parachute that will open automatically if he loses consciousness at mach speeds.Even if everything goes as planned, it wont. Baumgartner still will free fall at a speed that would cause you and me to pass out, and no parachute is guaranteed to work higher than 25,000 feet (7,
25、620 meters).It might not be the moon, but Kittinger free fell from 102,800 feet in 1960 - at the dawn of an infamous space race that captured the hearts of many. Baumgartner will attempt to break that record, a feat that boggles the mind. This is one of those monumental moments I will always remember, because there is no way Id miss this.
