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Effect of arc distance on temperature field and weld shape during double-sided arc welding
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作者 张广军 张华军 +1 位作者 高洪明 吴林 《China Welding》 EI CAS 2009年第1期23-28,共6页
A new high efficiency welding method, double-sided double arc welding with double powers (DSAW-D), is developed for thick plate of low alloy high strength steel in this study. It is well known that the thermal cycle... A new high efficiency welding method, double-sided double arc welding with double powers (DSAW-D), is developed for thick plate of low alloy high strength steel in this study. It is well known that the thermal cycles have an important influence on the microstructure, shape, stress, distortion and mechanical property. The DSA W-D method can control the temperature field on a wide range by regulating the distance between two arcs, improve the microstructure and prevent hot and cold cracking of high strength steel. But at present, the effect of arc distance on the temperature field and shape is not clear. Therefore, the paper researches the effect of arc distance on the temperature field and weld pool during DSAW-D using finite element method. The transient temperature field of different arc distance in DSAW-D is calculated. To verify the numerical results, the temperature is measured by the thermo-couple and the calculated results agree approximately with experimental data. Farther, the thermal property and mutual effect of double-sided arcs are investigated. The temperature distributions and weld pool profile at different arc distances are obtained. The results show that arc distance is a very important factor to affect the heat process. 展开更多
关键词 double-sided arc welding temperature field weld pool numerical simulation arc distance
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Microstructures and hardness of flat-overhead weld of the high strength steel thick plate using double-sided arc welding
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作者 李大用 易晓丹 张广军 《China Welding》 EI CAS 2015年第4期33-38,共6页
High strength steel thick plate is widely used in shipbuilding, pressure vessels, etc. , the balance between weld quality and welding efficiency is becoming a research focus. In this paper, double-sided double arc fia... High strength steel thick plate is widely used in shipbuilding, pressure vessels, etc. , the balance between weld quality and welding efficiency is becoming a research focus. In this paper, double-sided double arc fiat-overhead welding experiments for high strength steel thick plate were conducted. Microstructures of weld have been observed through optical microscope (OM) and scanning electron microscope (SEM). Transformation of microstructures under thermal cycles of multi peaks was analyzed. Macro and micro hardness were also tested. The results show that the heat-affected zone (HAZ) near the fusion line experiences thermal cycles up to three times. The microstructures there are the most complex, including coarse lath martensite in original coarse-grained zone, and net-like structure along grain boundaries in critical reheat coarse-grained zone. After several times of tempering for bucking welding, the features of acicula and lath are weakened. Its microstructure approaches to the microstructure of base metal which is tempering sorbite. The hardness test shows that the maximum hardness occurs at critical reheat coarse-grained zone, the hardness of reticulation structure at grain boundary can be up to 450 HV. 展开更多
关键词 net-like microstructure thermal cycle double-sided arc welding high-strength steel
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Numerical simulation of dynamic thermal process during doublesided asymmetrical TIG backing welding of large thick plates 被引量:2
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作者 刘殿宝 赵慧慧 +2 位作者 李福泉 张广军 吴林 《China Welding》 EI CAS 2011年第1期44-48,共5页
The dynamic thermal process during double-sided asymmetrical TIG backing welding of large thick plates ( 1 000 mm×700 mm×50 mm) is numerically simulated using MSC. MARC. The effect of arc distance on the t... The dynamic thermal process during double-sided asymmetrical TIG backing welding of large thick plates ( 1 000 mm×700 mm×50 mm) is numerically simulated using MSC. MARC. The effect of arc distance on the thermal cycle in weld zone during double-sided asymmetrical T1G backing welding is investigated. The results show that the workpiece experiences double-peak thermal cycle in double-sided asymmetrical TIG backing welding. On the one hand, the fore arc has the pre- heating effect on the rear pass, and the pre-heating temperature depends on the distance between the double arcs, the heat input of fore arc, and the initial temperature of workpiece. On the other hand, the rear arc has the post-heating effect on the fore pass. The mutual effects of two heat sources decrease with the increase of arc distance. 展开更多
关键词 numerical simulation double-sided asymmetrical TIG backing welding thermal process double heat sources on double sides
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Double-sided gas tungsten arc welding process on TC4 titanium alloy 被引量:3
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作者 高洪明 白岩 杨天东 《中国有色金属学会会刊:英文版》 EI CSCD 2005年第5期1081-1084,共4页
TC4 titanium alloy was welded by double-sided gas tungsten arc welding(GTAW) process in comparison with conventional GTAW process, the microstructure and mechanical performance of weld were also studied. The results i... TC4 titanium alloy was welded by double-sided gas tungsten arc welding(GTAW) process in comparison with conventional GTAW process, the microstructure and mechanical performance of weld were also studied. The results indicate that double-sided GTAW is superior over regular single-sided GTAW on the aspects of increasing penetration, reducing welding deformation and improving welding efficiency. Good weld joint was obtained, which can reach 96.14% tensile strength and 70.85% elongation percentage of the base metal. The grains in heat-affected zone(HAZ) are thin and equiaxed and the degree of grain coarsening increases as one moves to the weld center line, and the interior of grains are α and α′ structures. The coarse columned and equiaxed grains, which interlace martensitic structures α′ and acicular α structures, are observed in weld zone. The fracture mode is ductile fracture. 展开更多
关键词 焊接工艺 定位焊接 钛合金 气压焊接 微观结构
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Numerical Simulation of Current Density Distribution in Keyhole Double-Sided Arc Welding 被引量:3
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作者 JunshengSUN ChuansongWU +1 位作者 MinZHANG HouxiaoWANG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第2期228-231,共4页
In the double-sided arc welding system (DSAW) composing of PAW+TIG arcs, the PAW arc is guided by the TIG arc so that the current mostly flows through the direction of the workpiece thickness and the penetration is gr... In the double-sided arc welding system (DSAW) composing of PAW+TIG arcs, the PAW arc is guided by the TIG arc so that the current mostly flows through the direction of the workpiece thickness and the penetration is greatly improved. To analyze the current density distribution in DSAW is beneficial to understanding of this process. Considering all kinds of dynamic factors acting on the weldpool, this paper discusses firstly the surface deformation of the weldpool and the keyhole formation in PAW+TIG DSAW process on the basis of the magnetohydrodynamic theory and variation principles. Hence, a model of the current density distribution is developed. Through numerical simulation, the current density distribution in PAW+TIG DSAW process is quantitatively analyzed. It shows that the minimal radius of keyhole formed in PAW+TIG DSAW process is 0.5 mm and 89.5 percent of current flows through the keyhole. 展开更多
关键词 PAW+TIG double-sided arc welding Surface deformation of the weldpool KEYHOLE Current density distribution
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Microstructure of stainless steel weld in double-sided arc welding
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作者 董红刚 王兵 +2 位作者 杨丽群 高洪明 吴林 《China Welding》 EI CAS 2010年第2期6-11,共6页
Double-sided arc welding with a single power source can effectively increase the weld penetration, diminish distortion, improve welding speed and save energy. Compared to conventional arc welding processes, double-sid... Double-sided arc welding with a single power source can effectively increase the weld penetration, diminish distortion, improve welding speed and save energy. Compared to conventional arc welding processes, double-sided arc welding can generate a penetrating electromaguetic field to help to form fine dendritic microstrueture in the weld due to the symmetry of heating. Type 1Cr1SNi9Ti aastenitic stainless steel was bead-on-plate welded with double-sided arc welding and conventional plasma arc welding processes, respectively, and microstructure in the weld, heat-affected zone and base metal were examined. After analyzing the black carbon-enriched band in the weld during plasma arc welding with electron probe microanalyzer ( EPMA ) and X-ray diffraction (XRD) technology, it was found that the black band was shaped from the aggregation of ferrite in the fasion boundary. Hardness measurement showed that this black band does not apparently affect the microhardncss distribution in the weld. 展开更多
关键词 double-sided arc welding stainless steel MICROSTRUCTURE carbon-enriched band
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Virtual Speed Sensorless Desired Control Strategy of Maglev Single-sided Linear Induction Motors 被引量:3
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作者 DENG Jiangming CHEN Tefang TANG Jianxiang ZHANG Guixin YU Mingyang 《中国电机工程学报》 EI CSCD 北大核心 2012年第27期I0006-I0006,182,共1页
单边短初级长次级直线感应电机己普遍应用于低速磁悬浮的驱动系统。由于在动态纵向边端效应影响下等效电路不对称,单边直线感应电机(single-sided linear inductionmotor,SLIM)的一些参数非线性变化。传统的应用于旋转电机的无速度... 单边短初级长次级直线感应电机己普遍应用于低速磁悬浮的驱动系统。由于在动态纵向边端效应影响下等效电路不对称,单边直线感应电机(single-sided linear inductionmotor,SLIM)的一些参数非线性变化。传统的应用于旋转电机的无速度传感器方法不再适用。首先分析了SLIM的M/T轴等效电路,选择次级磁链作为速度观测器状态变量。根据李雅普诺夫系统稳定性判据,推导出适用于SLIM的无速度传感器辨识;然后,采用反馈广义积分观测器控制稳态辨识速度的双幅脉振幅值;引入虚拟期望变量(virtualdesiredvariable,VDV)法,利用估算速度参与SLIM的恒滑差频率矢量控制。仿真与实验对所提控制算法的有效性和实用性进行了验证,所得结论可为磁悬浮的无速度传感器控制提供参考。 展开更多
关键词 无速度传感器控制 直线感应电机 磁悬浮 控制策略 直线感应电动机 单面 虚拟 SLIM
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Penetration mechanism of aluminum alloy in double-sided GTAW process
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作者 高洪明 吴林 董红刚 《中国有色金属学会会刊:英文版》 CSCD 2005年第S2期35-38,共4页
The penetration mechanism of aluminum alloy in double-sided gas tungsten arc welding (GTAW) process was probed by means of theoretical analysis, experimentation and numerical simulation. The results show that, firstly... The penetration mechanism of aluminum alloy in double-sided gas tungsten arc welding (GTAW) process was probed by means of theoretical analysis, experimentation and numerical simulation. The results show that, firstly, the welding current goes straight through the weld zone, forms a stronger electromagnetic force field, and causes a stronger fluid flow in the weld pool. Secondly, during double-sided GTAW process, when the weld is partial penetrated, a heat-congregated zone forms between the bottoms of the two weld pools, where the temperature can increase quickly even though only a small amount of heat is input. Thirdly, the buoyancy force causes an inward flow in the bottom weld pool, which can drive the hot liquid on the surface to the bottom of the pool. 展开更多
关键词 ALUMINUM alloy double-sided GTAW PROCESS WELD PENETRATION numerical simulation
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Study on heat efficiency of laser-TIG double-side welding 被引量:1
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作者 苗玉刚 李俐群 +1 位作者 陈彦宾 吴林 《China Welding》 EI CAS 2008年第1期64-70,共7页
A series of laser-TIG double-side welding experiments for aluminum alloys were carried out to investigate the heat efficiency of the process. The melting efficiency was introduced to evaluate quantitatively the degree... A series of laser-TIG double-side welding experiments for aluminum alloys were carried out to investigate the heat efficiency of the process. The melting efficiency was introduced to evaluate quantitatively the degree of the mutual effect of the laser and the arc. The results showed that the melting efficiency of laser-TIG double-side welding exceeded the sum of the laser and the arc taken separately. With the increase of heat input, the weld depth and melting efficiency of the laser and the arc were increased signifwantly. This, in fact, implies the strong mutual effect of the laser and the arc as heat sources joined simultaneously in the process. Comparatively, the higher efficiency of the laser constituent of heat sources plays the main role in the increase of the process efficiency. The phenomena of arc column convergence, increased laser absorptivity and the formation of heat accumulation region are the causes of the improvement of heat efficiency. 展开更多
关键词 laser-TIG double-side welding melting efficiency arc column convergence heat accumulation region
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Effect of laser parameters on arc behavior of laser-TIG double-side welding for aluminum alloy
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作者 苗玉刚 李俐群 +2 位作者 张新戈 陈彦宾 吴林 《China Welding》 EI CAS 2010年第4期15-19,共5页
The influence of laser parameters on are beharior of laser-TIC, dauble-side welding was investigated by utilizing CCD sensor and intage processing methods. It was found that are images had an obvious transformation fr... The influence of laser parameters on are beharior of laser-TIC, dauble-side welding was investigated by utilizing CCD sensor and intage processing methods. It was found that are images had an obvious transformation from laser preheating to laser plasma ejected from the keyhole bottom, resulting in the phenomena of arc column convergence and arc root constrictian. The attraction phenomenon of the laser and the arc is also found in laser-TIG double-side welding. More noteworthy is that the behavior of arc attraction or constriction became much obvious at a lower current or laser plasma ejected from the keyhole bottom. The decrease in arc voltage had a certain relation u'ith the improvement of arc stabilio. 展开更多
关键词 laser-TIG double-side welding arc image arc constriction attraction phenomenon
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单通道脊柱内镜与单边双通道脊柱内镜技术治疗腰椎管狭窄症临床疗效分析
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作者 李想 贺海怿 +5 位作者 李鹏 马琳 郭强 张鹏飞 张凯 聂富祥 《颈腰痛杂志》 2024年第5期834-839,844,共7页
目的探讨单通道脊柱内镜与单边双通道脊柱内镜技术在腰椎管狭窄症的手术减压情况、术后疗效和手术安全性。方法收集该科自2020年7月~2022年7月开展脊柱内镜手术治疗的79例LSS患者资料(包括单通道脊柱内镜手术33例,纳入单通道组;单边双... 目的探讨单通道脊柱内镜与单边双通道脊柱内镜技术在腰椎管狭窄症的手术减压情况、术后疗效和手术安全性。方法收集该科自2020年7月~2022年7月开展脊柱内镜手术治疗的79例LSS患者资料(包括单通道脊柱内镜手术33例,纳入单通道组;单边双通道脊柱内镜手术46例,纳入双通道组)。对两组患者的围手术期指标和疗效指标、减压节段椎间隙硬膜囊横截面积进行分组比较。结果两组患者的手术时间、住院时间和手术并发症情况比较,差异均不显著(P>0.05)。与术前相比较,两组患者术后1个月的腰痛、下肢痛VAS和ODI评分均明显改善(P<0.05),术后12个月这3项指标均进一步改善(P<0.05);上述3项指标的两组间比较,差异均不显著(P>0.05)。术后12个月时,单通道组的优良率90.1%(30/33),双通道组为91.3%(42/46),两组差异不显著(P>0.05)。与术前相比,两组患者术后1个月的硬膜囊横截面积均明显增加(P<0.05),且双通道组的硬膜囊横截面积和术后增加值均显著大于单通道组(P<0.05)。结论单通道与单边双通道脊柱内镜减压术治疗腰椎管狭窄症均可获得满意的减压效果,单通道脊柱内镜手术仅需单一切口,创伤相对更少;而单边双通道脊柱内镜手术则操作更为灵活,减压更为彻底。 展开更多
关键词 腰椎管狭窄症 脊柱微创手术 单通道内镜 单边双通道内镜
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协同双面搅拌摩擦焊接技术
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作者 李文亚 唐益爽 +1 位作者 邹阳帆 王卫兵 《航空制造技术》 CSCD 北大核心 2024年第13期14-19,共6页
协同双面搅拌摩擦焊接(SDS-FSW)作为搅拌摩擦焊接技术的一种新的改进形式,显著改善了传统搅拌摩擦焊接变形大、焊接效率低等问题,对焊接质量也有提升作用,适用于大尺寸、大厚度的板材或型材的焊接。但目前SDS-FSW仍处于初始研发阶段,相... 协同双面搅拌摩擦焊接(SDS-FSW)作为搅拌摩擦焊接技术的一种新的改进形式,显著改善了传统搅拌摩擦焊接变形大、焊接效率低等问题,对焊接质量也有提升作用,适用于大尺寸、大厚度的板材或型材的焊接。但目前SDS-FSW仍处于初始研发阶段,相关的理论及应用研究较少,研究成果主要集中在6061铝合金上。本文主要介绍SDS-FSW技术的发展历程、技术特点与典型研究结果及应用前景,以期为SDS-FSW技术的发展及实际工程推广提供参考。 展开更多
关键词 搅拌摩擦焊接(FSW) 协同双面搅拌摩擦焊接(SDS-FSW) 铝合金 显微组织 力学性能
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单边双针双线摆动缝合轨迹设计及实验验证
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作者 高子乔 董九志 +1 位作者 陈云军 蒋秀明 《中国机械工程》 EI CAS CSCD 北大核心 2024年第1期102-108,共7页
针对单边双针双线缝合头插刺机构无法缝制3 mm以上厚度预制体的问题,提出一种不对称的8字形运动轨迹并对插刺机构的运动轨迹进行了设计。首先,基于单边双针双线缝合工艺对插刺机构运动学进行分析,确定摆动插刺机构各构件的尺寸;其次,在A... 针对单边双针双线缝合头插刺机构无法缝制3 mm以上厚度预制体的问题,提出一种不对称的8字形运动轨迹并对插刺机构的运动轨迹进行了设计。首先,基于单边双针双线缝合工艺对插刺机构运动学进行分析,确定摆动插刺机构各构件的尺寸;其次,在ADAMS中构建机构模型并进行轨迹分析;最后,通过实验样机进行缝合实验。实验结果表明,设计的缝合机构可将实际缝合厚度不足3 mm提高到8 mm,并在缝合过程中形成稳定线环,验证了不对称8字形缝合工艺及摆动插刺机构的可靠性。 展开更多
关键词 单边双针双线缝合 轨迹设计 摆动插刺机构设计 实验验证
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厚板5A06铝合金万瓦级扫描激光立焊组织与性能
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作者 方迪生 凡园园 +3 位作者 黄瑞生 徐富家 裴亮 李嘉实 《焊接学报》 EI CAS CSCD 北大核心 2024年第6期68-76,共9页
针对厚板铝合金万瓦级常规激光焊接往往存在焊缝成形差和气孔缺陷严重的问题,文中提出了厚板铝合金万瓦级扫描激光立焊方法,采用厚板5A06铝合金进行了焊接工艺试验,并综合分析了焊接接头焊缝成形、微观组织、力学性能.结果表明,该方法... 针对厚板铝合金万瓦级常规激光焊接往往存在焊缝成形差和气孔缺陷严重的问题,文中提出了厚板铝合金万瓦级扫描激光立焊方法,采用厚板5A06铝合金进行了焊接工艺试验,并综合分析了焊接接头焊缝成形、微观组织、力学性能.结果表明,该方法有效的改善了厚板铝合金常规激光的焊缝成形,且减少了气孔缺陷.根据熔池形貌图像,扫描激光大幅增加了熔池尺寸,因此熔池尾部受熔池前沿激光干扰减弱,有利于改善熔池尾部焊缝成形和减少气孔缺陷.针对厚度为50 mm铝合金板,采用万瓦级扫描激光立焊实现了窄间隙坡口形式24 mm厚钝边的双面双道焊接.当扫描幅度增大时,即焊接参数Ⅱ和Ⅲ,焊缝均匀光滑,成形良好,且X射线探伤未见气孔缺陷.焊接参数Ⅱ接头微观组织全部由等轴晶构成,焊接参数Ⅲ接头由等轴晶和少量柱状晶构成.由于焊接参数Ⅲ焊接速度小,热输入更大,焊接参数Ⅲ接头晶粒尺寸更大.焊接参数Ⅱ和Ⅲ接头抗拉强度为337 MPa和322 MPa,分别达到了母材的93.6%和89.4%,焊缝性能良好.焊缝拉伸断口均呈现韧窝形态,为韧性断裂. 展开更多
关键词 厚板铝合金 扫描激光 双面焊 立焊 焊缝性能
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压力管道工程中有关焊接诸多认知误区和盲区浅析(一)——焊接接头
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作者 应道宴 汤晓英 +1 位作者 尤子涵 余鑫萍 《化工设备与管道》 CAS 北大核心 2024年第4期85-91,共7页
焊接接头形式和焊缝形式是两个不同概念,而压力管道单面焊焊接接头要达到相当于双面焊同样质量要求是一个综合性的问题,主要涉及焊接方法、母材类别、焊接材料、焊接位置、预热、背面充气保护、热处理、电特性及技术措施等9个因素的影响... 焊接接头形式和焊缝形式是两个不同概念,而压力管道单面焊焊接接头要达到相当于双面焊同样质量要求是一个综合性的问题,主要涉及焊接方法、母材类别、焊接材料、焊接位置、预热、背面充气保护、热处理、电特性及技术措施等9个因素的影响,同时也与焊工技能有关。熟练焊工按照合格的焊接工艺评定进行施焊、加强焊缝目视检测(VT),尤其是焊接接头坡口加工和焊道VT检测是保障质量的重要要素。 展开更多
关键词 压力管道焊接 焊接接头 焊缝 单面焊 双面焊 坡口准备 目视检测 不锈钢焊管
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U肋全熔透焊接正交异性板构造疲劳性能试验研究
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作者 汪金辉 李雪健 《世界桥梁》 北大核心 2024年第3期104-110,共7页
为研究U肋与钢桥面不同焊接工艺接头的疲劳性能,以主跨408 m的中承式连续钢桁拱桥——武汉汉江湾桥主桥为背景,在传统单面埋弧焊基础上,提出一种先平位内焊再船位外焊的双面埋弧全熔透焊接技术,制作不同焊接工艺U肋与钢面板试件,开展丁... 为研究U肋与钢桥面不同焊接工艺接头的疲劳性能,以主跨408 m的中承式连续钢桁拱桥——武汉汉江湾桥主桥为背景,在传统单面埋弧焊基础上,提出一种先平位内焊再船位外焊的双面埋弧全熔透焊接技术,制作不同焊接工艺U肋与钢面板试件,开展丁字接头弯曲疲劳试验、焊接接头拉伸疲劳试验及3种典型构造细节疲劳试验,分析U肋与钢面板构造细节疲劳性能。结果表明:不同焊接方式下U肋与钢面板的疲劳强度差异明显,埋弧焊丁字接头的疲劳强度较高,大于342 MPa。U肋与钢面板双面埋弧熔透焊试件轴向拉伸状态下最低疲劳强度121.6 MPa,在-50~50 MPa拉-压循环应力幅和100 MPa拉应力幅下试件均未开裂;在120 MPa拉应力幅下,疲劳开裂加载次数均大于200万次,顶板内侧焊缝焊趾发生疲劳开裂。U肋与钢面板双面埋弧全熔透焊接构造细节疲劳性能优于单面焊及不开坡口的双面焊部分熔透构造细节,可以提高结构的耐久性和使用寿命。 展开更多
关键词 钢桥 正交异性钢桥面板 U肋与钢面板构造细节 双面埋弧全熔透焊接 疲劳性能 疲劳试验
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圆环工件双面直焊缝自动焊接装置设计
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作者 刘叶 吉晓民 《机电工程技术》 2024年第9期196-200,共5页
圆环工件广泛应用于制造业中,针对圆环工件加工过程中的双面直焊缝焊接问题,设计一种基于PLC控制的圆环工件双面直焊缝自动焊接装置,主要包括机械结构模块和运动控制模块。机械结构包括龙门架、横向移动机构、纵向移动机构、焊枪回转机... 圆环工件广泛应用于制造业中,针对圆环工件加工过程中的双面直焊缝焊接问题,设计一种基于PLC控制的圆环工件双面直焊缝自动焊接装置,主要包括机械结构模块和运动控制模块。机械结构包括龙门架、横向移动机构、纵向移动机构、焊枪回转机构、工件旋转机构、送丝模块以及控制柜体;运动控制模块包括人机触摸屏HMI、可编程逻辑控制器PLC、电机驱动器、电磁阀和微型光电传感等。通过操作运动控制模块的HMI触摸屏来控制机械结构模块各机构执行相应动作流程,使得各机构互相配合完成圆环工件双面直焊缝的自动焊接。运动仿真结果表明,该装置结构简单、控制方便、可完成圆环工件双面直焊缝自动焊接,提高了焊接效率和焊接质量。 展开更多
关键词 直焊缝 双面焊接 龙门架机构 PLC控制
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改良单孔加一孔腹腔镜右半结肠癌根治术的临床效果
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作者 曾之耀 邓海军 +3 位作者 刘丙刚 唐兵 屈海波 周湘茂 《中国现代手术学杂志》 2024年第4期269-274,共6页
目的探讨改良单孔加一孔腹腔镜(single-incision plus one-port laparoscopic surgery,SILS+1)右半结肠癌根治术的安全性及有效性。方法采用回顾性病例对照研究。选取2019年1月到2024年6月我院收治的行SILS+1右半结肠癌根治术患者34例... 目的探讨改良单孔加一孔腹腔镜(single-incision plus one-port laparoscopic surgery,SILS+1)右半结肠癌根治术的安全性及有效性。方法采用回顾性病例对照研究。选取2019年1月到2024年6月我院收治的行SILS+1右半结肠癌根治术患者34例。其中对照组23例,行经典的SILS+1右半结肠癌根治术,切口采用3~4 cm绕脐切口+左中腹1.2 cm戳孔;研究组11例,行改良SILS+1右半结肠癌根治术,切口采用3~4 cm下腹部横切口+左中腹1.2 cm戳孔。比较两组的手术时间、出血量、淋巴结清除数量、术后首次肛门排气时间、术后1 d疼痛视觉模拟评分(visual analogue scale,VAS)、术后住院时间等。结果两组出血量、淋巴结清除数量、术后首次肛门排气时间无明显差异(P>0.05);手术时间、术后1 d的VAS及术后住院时间有差异,研究组优于对照组(P<0.05)。结论改良单孔(下腹部横切口)加一孔(左中腹1.2 cm戳孔)腹腔镜右半结肠癌根治手术安全有效,且较绕脐切口手术时间及术后住院时间更短,术后疼痛更轻,手术切口更加美观和隐蔽,值得临床推广应用。 展开更多
关键词 结肠肿瘤 右半结肠癌根治术 腹腔镜 单切口加一孔 双切口 手术入路
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厚板双面四丝单道埋弧焊接工艺参数设计及应用
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作者 唐子金 《焊管》 2024年第8期55-58,共4页
结合焊缝熔深与四丝单道埋弧焊一丝焊接参数、钢板壁厚、坡口深度的函数关系,及焊丝填充面积与四丝单道埋弧焊一丝~四丝焊接参数、坡口深度、坡口角度的函数关系,设计厚板双面四丝单道埋弧焊接的焊接坡口尺寸及对应的焊接参数。依据此... 结合焊缝熔深与四丝单道埋弧焊一丝焊接参数、钢板壁厚、坡口深度的函数关系,及焊丝填充面积与四丝单道埋弧焊一丝~四丝焊接参数、坡口深度、坡口角度的函数关系,设计厚板双面四丝单道埋弧焊接的焊接坡口尺寸及对应的焊接参数。依据此参数进行32 mm、40 mm和50 mm厚板双面四丝单道埋弧焊接试验。结果表明,设计的焊接工艺参数既可保证厚板大钝边尺寸双面焊接焊透,又能保证厚板大坡口截面填满,并可获得良好的焊接质量。 展开更多
关键词 厚板 双面四丝单道埋弧焊接 焊缝熔深 坡口深度
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Q345B钢MAG焊与激光-MAG复合焊对比研究
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作者 曹世杰 毕学松 +1 位作者 李志波 侯艳喜 《热加工工艺》 北大核心 2024年第17期38-41,共4页
对4 mm和8 mm厚的Q345B试板分别进行MAG焊和激光-MAG复合焊的工艺试验研究,分析焊缝成形,检测焊接接头宏观形貌、拉伸性能和弯曲性能。结果显示:相对于常规MAG焊,激光-MAG复合焊能够实现单面焊背面无垫板的自由成形;焊接速度显著提高,... 对4 mm和8 mm厚的Q345B试板分别进行MAG焊和激光-MAG复合焊的工艺试验研究,分析焊缝成形,检测焊接接头宏观形貌、拉伸性能和弯曲性能。结果显示:相对于常规MAG焊,激光-MAG复合焊能够实现单面焊背面无垫板的自由成形;焊接速度显著提高,焊接作业效率提高一倍以上;焊材消耗减少,仅为MAG焊的22%~27%;焊接热输入小,焊后工件变形显著减小;焊接接头的拉伸和弯曲性能合格,满足实际工程应用要求。 展开更多
关键词 MAG焊 激光-MAG复合焊 单面焊双面成形 焊接工艺
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