焊接作业弧光危害及其防护对策

<正>电弧焊是目前主要的焊接工艺方法之一,电焊弧光可对眼睛造成严重的伤害,是焊工遭受的最大的职业危害因素。传统焊接面罩的缺陷是导致伤害产生的主要原因之一,而新式自动变光焊接面罩的使用则可有效降低电焊弧光造成的危害。焊接是集多门类、多学科技术为一体的成形技术。它作为一种精确、可靠、低成本、高技术的材料连接方法,未来仍将是制造业的重要加工手段。其中,电弧焊仍是主要的焊接工艺方法。在发展中国家,采用手工电弧焊的方式进行焊接,仍将占焊接作业的60%左右。     

焊接眼面部职业危害及个人防护用品的选择

正确、全面地识别焊接过程中的眼面部职业危害,了解自动变光焊接面罩的核心部件及工作原理,根据作业环境选择合适的防护用品,起到保护焊接工作者的目的的同时,提升焊接效率及质量。     

自动变光焊接滤光片关键性能指标研究

焊接防护对作业者的职业健康安全及产品质量至关重要,自动焊接防护产品随技术进步开始得到广泛应用,关键器件为自动变光焊接滤光片,衡量其防护性能的关键技术指标为响应时间。本文对自动变光焊接滤光片的防护原理,关键技术指标——响应时间,影响响应时间的因素进行了研究。     

铁电陶瓷自动变光焊接面罩的研制

铁电陶瓷是一种具有优良电控双折射效应的高科技材料。把铁电陶瓷及相关的技术应用于自动变光焊接面罩是一种创新。本文介绍了铁电陶瓷自动变光焊接面罩的工作原理、研制过程、技术关键和解决方法以厦产品的技术性能．同时也对此项成果下一步的产品化提出了技术改进的建议。     

自动变光焊接滤光片响应时间快速测试设备

自动变光焊接防护装备已在欧美国家得到广泛应用,其关键部件是自动变光焊接滤光片。响应时间是自动变光焊接滤光片的关键技术指标,目前国内缺乏响应时间快速测试技术。本文介绍了一种响应时间快速测试设备,可以满足符合欧洲标准及我国国家标准中的测试要求。     

焊接过程中有哪些有害气体,应如何进行防护

正主持人,你好:我们企业需焊接各类金属和钢板,请问:在焊接过程中有哪些有害气体?如何进行防护?武汉陶克匠陶克匠先生,你好:电焊操作时接触职业病危害因素,主要包括有害烟尘、有毒气体、噪声、弧光辐射、高频电磁场、放射线等。不同焊接方法所产生的职业病危害因素及危害程度各异。电焊操作时,要配备必要的个人防护用品,如采用符合要求的防护面罩及眼镜等,使用防护屏障,     

焊接面罩的发展历程

焊接面罩是一种焊工防护装备,也是重要焊接辅助工具。本文主要介绍自焊接面罩出现100多年以来,经历了众多的改进,从手持式焊接面罩到头戴式焊接面罩、从黑玻璃焊接面罩到自动变光焊接面罩、从单一功能焊接面罩到多种功能集结的焊接面罩。同时指出,基于材料和技术的进步,焊接面罩不会停止创新的步伐,焊接面罩将在保护焊工、提高焊接质量和效率方面扮演重要角色。     

焊工须防弧光辐射

焊工作业时,为预防弧光辐射事故的发生,应采取下述安全防护措施: (1)焊工必须使用有电焊防护玻璃的面罩。 (2)面罩应该轻便、成形合适、耐热、不导电、不导热、不漏光。 (3)焊工作业时,应穿白色帆布工作服,防止弧光灼伤皮肤。 (4)操作引弧时,焊工应该注意周围工人,以免强烈弧光伤害他人眼睛。 (5)在厂房内和人多的区域进行焊接时,尽可能地使用屏风板,避免周围人受弧光伤害。 (6)重力焊或装配定位焊时,要特别注意弧光的伤害,因此要求焊工或装配工应戴防光眼睛。     

自动变光焊接滤光镜关键性能指标测试方法探讨

为了验证不同的测试温度对自动变光焊接滤光镜转换时间测试结果的影响,首先介绍自动变光焊接滤光镜的结构和工作原理,然后对4套由不同公司生产的自动变光焊接滤光镜转换时间在不同温度下进行测试,并对测试结果进行比对分析。结论显示,不同温度对自动变光焊接滤光镜的转换时间测试结果有影响。     

分光光度计测量遮光号方法的研究——自动变光焊接滤光镜遮光号的测量

本文对自动变光焊接滤光镜的遮光号测量方法进行了研究,指出测量中要将分光光度计光源的偏振性与自动变光焊接滤光镜的偏振性结合考虑,并采用合理的方法、步骤及相应的数据处理程序。得到正确的测量结果,同时分析了分光光度计在自动变光焊接滤光镜多项指标测量中的局限性和重要作用。     

LFT-G注塑工艺在玻璃钢安全帽生产中的应用

玻璃钢安全帽因具有强度高、耐高温,耐水、酸、碱、油、化学腐蚀及良好的绝缘性等特点,被广泛应用于石油化工、矿山、电力、冶炼等多个行业。目前,玻璃钢安全帽的生产工艺仅有两种,一是手糊,二是模压。但这两种生产工艺不仅存在粉尘、噪声、有毒物质等多种职业危害因素,而且由于部分关键工序采用手工制作,因而造成玻璃钢安全帽的质量性能的不稳定。使用LFT-G（长纤维增强热塑性塑料颗粒）作为原材料,将注塑工艺引进玻璃钢安全帽的生产中,实现了玻璃钢安全帽的注塑生产。这种工艺,不仅职业危害因素大大减少,而且也因关键工序中不存在手工作业,从而大大增加了玻璃钢安全帽质量的稳定性,同时,由于LFT-G粒料的长度增加,经过加工后,安全帽成品中的纤维长度也会增加,使得安全帽的抗冲击性能等满足标准要求。为此,以LFT-G为基础的玻璃钢安全帽的注塑工艺具有广阔的应用前景。     

The effects of a mandatory motorcycle helmet law on helmet use and injury patterns among motorcyclist fatalities

BACKGROUND: The National Highway Traffic Safety Administration (NHTSA) has found that motorcycle helmets are 37% effective in preventing death and 65% effective in preventing brain injuries in a crash. Unfortunately, in 1995 Congress lifted federal sanctions against states without helmet laws and since then there have been a number of primary motorcycle helmet laws repealed or weakened. More lives could be saved and serious injuries avoided if there was increased helmet use throughout the United States. METHODS: This study analyzed helmet use and injury patterns among motorcycle riders in the United States involved in fatal crashes from 1995 through 2003 and compared the results between states with and without a primary helmet law. Age, sex, injury severity and helmet use are some of the variables obtained from the Fatality Analysis Reporting System (FARS). RESULTS: In the 20 states and the District of Columbia, which currently have a primary helmet law, 84.0% of fatally injured riders were wearing a helmet. In the 27 states with a secondary helmet law, 36.2% of fatalities used a helmet, and in the remaining three states with no law at all, helmet use dropped to 17.6%. In the two states (Arkansas and Texas) that changed from a primary helmet law to a secondary helmet law in 1997, helmet use decreased from 78.2% in 1996 to 31.7% in 2000. CONCLUSION: If all states were to enact a primary motorcycle helmet law, helmet use would dramatically increase while decreasing the number of motorcyclist head injuries and fatalities. IMPACT ON INDUSTRY: The results of this study will hopefully persuade law makers to enact primary helmet laws in all states throughout the nation. Helmet manufacturers can use this data to design more comfortable helmets while also improving upon the protective qualities of these safety devices.     

Risk compensation? The relationship between helmet use and cycling speed under naturalistic conditions

Introduction: An argument against mandatory helmet use is based on the idea of risk compensation, which means that cyclists might ride faster when wearing a helmet (Lardelli-Claret et al., 2003). However, questionnaire and experimental studies were unable to find evidence for this assumption (Fyhri et al., 2012; Fyhri & Philipps, 2013). Simultaneously, other factors with a potential role in helmet use and cycling speed, such as trip length and rider characteristics have been neglected in such considerations. The goal of the analysis presented in this paper was therefore to investigate the relationship between helmet use and cycling speed under naturalistic conditions while taking characteristics of cyclists and bicycles into account. Method: As part of a naturalistic cycling study, we equipped the bicycles of conventional and e-bike riders with data acquisition systems to record speed and trip distance. It included two cameras (one for the face of the participant, another one for the forward scenery). For the analysis presented in this paper, we used the data of 76 participants (28 conventional bicycles, 48 e-bikes). Results: In total, participants used their helmet for 56% of all trips. Helmets were used more frequently for longer trips. A linear mixed model, in which trip length, helmet use, bicycle type, age, and gender were used as predictors showed that helmet use did not play a significant role for cycling speed. Instead, all other factors that were analyzed, with the exception of gender, had a significant relationship to cycling speed. Discussion: The assumption of risk compensation as a result of the use of a helmet could not be confirmed. Instead, the findings seem to support the suggestion that cyclists who undertake trips at potentially higher speed levels are aware of their increased risk, and actively try to reduce it through the use of a helmet.     

辐射制冷技术在安全帽上的应用研究*

为缓解夏季配戴安全帽导致的头部高温不适,采用具有光谱选择特性的辐射降温涂料对安全帽表面光学性能进行改性,经光学测试,安全帽的太阳辐射反射率由45%提升至89%,大气窗口发射率由92%提升至95%。对安全帽进行降温效果测试,并基于测试结果建立热力学模型。结果表明:在阳光直射下,改性安全帽内部温度低于普通白色安全帽,温差最大12.2 ℃;在热力学模型中,即使在夏季最热时间段（12∶00～14∶00）,改性安全帽内部温度仍可比普通安全帽低8 ℃,预测平均评价值由普通安全帽的3.5降低至1.0,预测不满意百分比从100%降低至20%。     

有限元在安全帽设计中的应用

安全帽可以防止高空坠落物对人员头部造成伤害。在材料和工艺一定的前提下,安全帽的结构对发挥安全帽的作用尤为重要。本文首先对安全帽作用机理及使用情况进行分析,指出改善安全帽帽壳缓冲性能有利于更好地发挥安全帽的作用。然后简要介绍ANSYS的建模方案以及网格划分和自由度约束情况,通过对安全帽的ANSYS有限元分析,得出安全帽的变形和应变图,并通过分析安全帽从最低端到顶端的变形和应变情况,指出安全帽在撞击过程中的能力吸收规律,根据分析数据提出建立双层安全帽帽壳的改进方案,并再次通过有限元分析得出变形和应变图,验证了双层安全帽帽壳在缓冲方面更有效果,这种分析结果可以为安全帽帽壳的设计提供参考。     

Examination of factors associated with use rates after transition from a universal to partial motorcycle helmet use law

Objectives: Motorcycle riders account for a disproportionately high number of traffic injuries and fatalities compared to occupants of other vehicle types. Though research has demonstrated the benefits of helmet use in preventing serious and fatal injuries in the event of a crash, helmet use has remained relatively stable in the United States, where the most recent national estimates show a 64% use rate. Use rates have been markedly lower among those states that do not have a universal helmet law for all riders. In 2012, the state of Michigan repealed its longstanding mandatory helmet use law. In order to gain insights as to the effects of this legislative change, a study was conducted to examine short-term changes in helmet use and identify factors associated with use rates.

Methods: A statewide direct observation survey was conducted 1 year after the transition from a universal helmet law to a partial helmet law. A random parameters logistic regression model was estimated to identify motorcyclist, roadway, and environmental characteristics associated with helmet use. This modeling framework accounts for both intravehicle correlation (between riders and passengers on the same motorcycle) as well as unobserved heterogeneity across riders due to important unobserved factors.

Results: Helmet use was shown to vary across demographic segments of the motorcyclist population. Use rates were higher among Caucasian riders, as well as among those age 60 and above. No significant difference was observed between male and female riders. Use was also found to vary geographically, temporally, and with respect to various environmental characteristics. Geographically, helmet use rates tended to be correlated with historical restraint use trends, which may be reflective of riding environment and general differences in the riding population. To this end, rates were also highly variable based upon the type of motorcycle and whether the motorcyclist was wearing high-visibility gear.

Conclusions: The study results demonstrate the short-term reduction in helmet use following transition from a universal to partial motorcycle helmet law. The reduction in use is somewhat less pronounced than has been experienced in other states, which may be reflective of general differences among Michigan motorcyclists because the state has also generally exhibited higher use rates of seat belts and other forms of occupant protection. The study results also highlight potential target areas for subsequent education and public awareness initiatives aimed at increasing helmet use.     

浅谈国内外安全帽生产技术

安全帽作为对自然人头部受坠落物体或其他特定因素引起的伤害所采用的个人防护用品,越来越受到世界各国的安全防护行业的重视。特别是在发达国家,不断进行技术创新,更新安全帽标准。本文从安全帽技术领域方面．详细介绍各国制造安全帽常用材料的性能与特点,安全帽的模具材料、加工工艺、先进生产技术以及主要国家的安全帽检测标准差异。     

警用头盔的人机工程学分析

警用头盔是武警部队使用最为频繁的单兵防护用具,本文基于人机工程学的理论,用人机工程学的观点对武警部队现装备的警用头盔进行分析和探讨,提出解决途径的设想,展望警用头盔的发展前景。