www亚洲视频-www亚洲色图-www亚洲精品-www亚洲国产-青青草99热这里都是精品-青青草99热久久

Language:CHINESESENGLISH

Home > News > Guangzhou Steel remind you: slab steel welding crack control measures
CONTACT US
  • Address:Pingtang Industrial District, Shipeng Village, Shishan Town, Nanhai District, Foshan City,
  • Phone:0757-81002668/0757-63323396
  • Fax:0757-81196682
  • Contact:Ben Zheng/13826981293 Kerry Lu/13751224830
  • E-mail:sbs@sbsprefabhouse.com
  • URL:http://m.huihuitaotao.cn

Guangzhou Steel remind you: slab steel welding crack control measures

Time:[2015-6-3]  Hits:4735

Guangzhou Steel remind you: slab steel welding crack control measures
 

Guangzhou Steel slab steel member is large, plate thickness, weld deposit large, complex nodes, residual stress, prone to crack, affecting the quality of welding, which is important and difficult project quality control. Production of general measures are:
1, measures to prevent hot cracking
1) Control of the chemical composition of the weld. I.e. to reduce the low-melting eutectic composition readily segregation elements, such as sulfur and phosphorus content in the welding material and the base material is formed. Reduce the carbon content in the steel, can reduce the thermal cracking tendencies; improve Mn content can improve weld thermal cracking performance.
2) control of welding parameters and conditions. Control of welding current and welding speed, so that the aspect ratio of each cross section of the upper part of bead reach 1.1 to 1.2, can improve thermal cracking performance, while controlling the weld pool shape, do not form easily understood in sharp elongated bath a longitudinal weld surface thermal cracks. Preheat reduces tendency to form cracks; reasonable welding sequence can make the most of the weld at the smaller restraint of welding, reducing the tensile stress suffered weld shrinkage, thermal cracking tendency can be reduced.
2, cold cracking prevention measures
1) Before welding procedure qualification test performed to determine the process parameters.
2) preheat prevents cracking, as well as improve the performance of a certain action.
3) manual welding using low hydrogen electrodes alkaline E5Q / E55 type; CO: gas shielded arc welding flux cored wire can be used; a H08MnA submerged arc welding can be used F5021, and in strict accordance with the provisions drying. Drying temperature is 350-450 ℃, after dried at 100-150cC temperature for 1 ~ 2h, put insulation cylinder used with the check.
4) Choose a reasonable weld profile, in strict accordance with the drawings machining parts groove.
5) each side of the weld within the range of 30 ~ 50mm rust and water clean, reducing the source of hydrogen.
6) cracks often occur on the head welds and weld root, so tacking length, welding foot height and spacing should also make corresponding provisions. If you have to locate the weld in the groove proceeds, weld height should be less than 2/3 of the groove depth, the length should be greater than 40mm. If necessary, prior to tack welding is preheated. Before welding, positioning the weld inspection, it must be removed when re-welding cracks. Tack welding length and spacing, should be considered the base material thickness, structure length.
7) To reduce stress and prevent cracking during welding, the assembly should avoid forced assembly.
8) appropriate to increase the current, lower cooling rate, helps prevent the formation of hardened tissue.
9) Control interlayer temperature should be slightly higher preheat temperature.
10) Q345C soldering should be carried out after a slow cooling to slow cooling rate of the weld and heat affected zone and prevent cold cracking, respond promptly weldment insulation, that is immediately after welding weldment is heated to 250 to 350. And use of asbestos and other insulation 2.6h after air cooling can reduce the hydrogen content in the weld and prevent cold cracking, heating methods, with preheat before width.
Although Guangzhou Steel slab steel construction difficult, but as long as proper control measures, the proportion of component cracking will be greatly reduced, the project will significantly improve the quality of weld cracks will be avoided, can effectively control industrial building projects quality.

Copyright:佛山市勝邦鋼結(jié)構(gòu)有限公司 Foshan Shengbang Steel Structure Co., Ltd. Record Number:粵ICP備13078463號(hào)
主站蜘蛛池模板: 日本海鸣馆老头gay视频| 9984四虎永久免费网站| 99re国产精品视频首页| 91在线精品播放| 福利片在线观看免费高清视频| 91天堂最新在线观看| 日本特黄特色aaa大片免费欧| 6080新觉视午夜伦毛片| 欧美鲁| 欲之国太子双性h文| 久草综合在线| 777766超级精彩中特19lr| 久久线看观看精品香蕉国产| 中文字幕成人免费高清在线| 撞击她的娇嫩高h| 主人给的100个调教任务| 欧美日韩一区二区视频免费看| 亚洲一区中文字幕在线| 久久精品国产线看观看亚洲| 免费成人在线播放| 欧男同同性videos免费| 久热这里只有精品在线| 色戒被分腿进入图片| 中国chinese帅男gay| 日本视频免费高清一本18| 亚洲最大色网站| 99国产精品视频久久久久| 久热香蕉视频| 超h 高h 污肉1v1快穿| 91短视频免费在线观看| 久久青草精品2020最新款| 调教母狗| 久久久国产亚洲精品| 996久久国产精品线观看导航| 成人午夜小视频| 99视频精品在线| 日韩成人免费在线| 成人免费视频网| a在线观看视频| 亚洲自拍在线| bnb98免费选择影院|