速差自控器的标准现状及使用误区分析

目前,我国市场上销售的速差自控器中,有许多并不符合国家标准GB24544—2009《坠落防护速差自控器》要求,笔者从4点说明如何辨别产品是否符合现行国家标准,并详细解读速差自控器使用常见的五大误区。速差自控器(以下简称"速差器")是高处作业防坠落用品.     

双腿速差自控器的研究与开发

速差自控器是高空作业人员经常使用的个体坠落防护装置。传统的速差自控器只有一根安全带或安全绳,当工人需要从一个工位移动到另一个工位的时候,这种单根安全带或者安全绳就不能满足这样的需求。双腿速差自控器就解决了这样的问题,它可以使工人从一个工位移动到另一个岗位而不脱离连接,从而保护工人的安全。本文是针对一款双腿速差自控器的研究与开发,包括整机构成、工作原理、关键零部件选择和性能要求、不同国家地区对其性能的测试要求以及锁止速度和自由坠落距离计算等内容。     

速差自控器动态性能试验方法的改进

为施工人员选择和配置安全可靠的个人防坠器,每年送到具有相应资质的检测单位进行强制检定,是防止高处坠落事故的重要手段。某型速差自控器在冲击试验中发生了钢丝绳断裂事故,为了查找和分析事故的真正原因,对不同厂家的速差自控器抽样,在相同试验方法和检测条件下进行冲击试验,并根据相关的标准对试验结果进行力学性能对比分析研究,找到了造成钢丝绳断裂事故的主要原因是该类型速差自控器使用的钢丝绳直径偏细以及缺少内部或外部缓冲器,研究中还发现部分国内标准技术要求不够明确,制造、检测和使用方对速差自控器相关标准理解存在偏差,是造成本次事故的间接原因。针对现有的部分速差自控器产品存在的质量问题,并根据现行最新标准和实际工作条件,提出改进了的检测方法和防范措施,从源头上防范坠落事故。     

密封式速差自控器在海上风电的应用

在海上风机上使用速差自控器时,仍然处于海洋大气区,还是要考虑到防腐蚀的问题。密封式速差自控器正是为高腐蚀环境使用而设计的产品。本文介绍了密封式速差器的工作方式,衡量其对外界异物进入的防护能力的方法和耐腐蚀测试方法。     

高空作业者的福音──TS系列速差自控器

浙江省乐清县劳保用品厂研制的力士牌速差自控器(见封4广告),1987年12月在《全国劳动保护、安全生产技术展览会》.上展出时。受到了参观者的一致好评。1988年通过省级鉴定;专家们认为,这项产品具有较高水平,填补了国内高处作业防坠落用品的一项空白。目前,ISO国际标准化组织已规定推广使用。 传统的高处作业个人安全防护用品为安全带(绳)。使用这种防护用品,作业人员只能在某个作业点的小范围内活动。若为了扩大作业范围而把安全带(绳)加长,在正常作业中,过长的带(绳)会妨碍行动;一旦作业人员失足坠落,过大的落差会产生很大的冲击力。严重…     

坠落防护用品选并穿对了吗

高处坠落一直是建筑领域多发易发的事故,如何减少此类事故的发生,穿戴好合适的防坠落防护用品,仍然是最后一道防线。本文通过建筑领域作业的不同类型,介绍防护用品的选择与使用,让防护用品发挥其减少事故的应有作用。     

高空作业个体安全防护的先进装置──TS系列速差自控器

传统的高空作业个体安全防护工具是安全带(绳)。使用这种防护工具,对保证作业安全是有效的,但作业人员只能在某个作业点很小的作业范围内活动。作业者如果为扩大活动范围而把安全带(绳)加长,就会产生新的问题,一旦失足坠落,会因产生很大的冲击力而使人体受到严重的损伤。此外,过长的安全带(绳)会妨碍正常的作业。 最近,浙江省乐清劳动保护用品厂在有关科研单位的支持下,研制出TS系列安全带速差自控器,妥善地解决了保证安全与方便工作的矛盾。 这种装置类似钢卷尺,钢丝绳一端系于固定轴,另一端与系于人体上的安全带相连,操作者可在半径有3米…     

我国坠落防护装备标准体系的构建与发展

为持续改进我国坠落防护装备标准体系,本文首先对坠落防护装备和坠落防护系统进行介绍;其次对3个国际主流坠落防护装备标准体系进行分析,并梳理我国坠落防护装备标准体系的构建过程及包含的主要标准;最后对我国坠落防护装备标准体系存在的问题进行分析并提出发展规划的建议。结果显示:我国坠落防护装备标准体系存在标准缺乏统一性、管理标准滞后于社会发展、缺少新产品标准规范等问题,针对问题提出可通过落实标准化基础工作、完善标准体系建设、加强标准修订和更新工作等措施完善我国坠落防护装备标准体系。     

关于个人防坠落装备标准化的探讨

我国是职业安全事故的多发国家。有关数据表明：1990年以来我国各类事故死亡总量每年以超过秭的速度在增长。与GDP增长速度基本同步。而职业事故的死亡率是发达国家的，屿倍，死亡率最高的三大行业为煤矿、建筑和交通。其中坠落事故死亡率约占9．8%。本文将以个人防坠落装备现行国内标准和国际标准之间的差距为出发点，对我国防坠落装备市场进行分析，探讨防坠落装备标准化的工作思路。     

高处作业的安全防护

高处作业是企业中常见的作业之一，其坠落事故时有发生。高处坠落的致因多种多样。比如，当操作人员在离地面很高的位置，即使是在高10米处施工，如果周围是封闭的或者防护措施很有效，也不会发生坠落事故；反之，如果缺少防护措施，即使是在离地面仅2米左右的地方施工，也会失足坠落，导致人员伤亡的严重后果。     

Driver speed selection on high-speed two-lane highways: Comparing speed profiles between uniform and differential speed limits

Objective: Although a considerable amount of prior research has investigated the impacts of speed limits on traffic safety and operations, much of this research, and nearly all of the research related to differential speed limits, has been specific to limited access freeways. The unique safety and operational issues on highways without access control create difficulty relating the conclusions from prior freeway-related speed limit research to 2-lane highways, particularly research on differential limits due to passing limitations and subsequent queuing. Therefore, the objective of this study was to assess differences in driver speed selection with respect to the posted speed limit on rural 2-lane highways, with a particular emphasis on the differences between uniform and differential speed limits.

Methods: Data were collected from nearly 59,000 vehicles across 320 sites in Montana and 4 neighboring states. Differences in mean speeds, 85th percentile speeds, and the standard deviation in speeds for free-flowing vehicles were examined across these sites using ordinary least squares regression models.

Results: Ultimately, the results of the analysis show that the mean speed, 85th percentile speed, and variability in travel speeds for free-flowing vehicles on 2-lane highways are generally lower at locations with uniform 65 mph speed limits, compared to locations with differential limits of 70 mph for cars and 60 mph for trucks.

Conclusions: In addition to posted speed limits, several site characteristics were shown to influence speed selection including shoulder widths, frequency of horizontal curves, percentage of the segment that included no passing zones, and hourly volumes. Differences in vehicle speed characteristics were also observed between states, indicating that speed selection may also be influenced by local factors, such as driver population or enforcement.     

遥控器在桥式起重机上的应用

在桥式起重机上加装遥控装置,既解决了操作者的上下车之苦,又确保了安全生产。     

Perils of using speed zone data to assess real-world compliance to speed limits

Objective: Real-world driving studies, including those involving speeding alert devices and autonomous vehicles, can gauge an individual vehicle's speeding behavior by comparing measured speed with mapped speed zone data. However, there are complexities with developing and maintaining a database of mapped speed zones over a large geographic area that may lead to inaccuracies within the data set. When this approach is applied to large-scale real-world driving data or speeding alert device data to determine speeding behavior, these inaccuracies may result in invalid identification of speeding. We investigated speeding events based on service provider speed zone data.

Methods: We compared service provider speed zone data (Speed Alert by Smart Car Technologies Pty Ltd., Ultimo, NSW, Australia) against a second set of speed zone data (Google Maps Application Programming Interface [API] mapped speed zones).

Results: We found a systematic error in the zones where speed limits of 50–60 km/h, typical of local roads, were allocated to high-speed motorways, which produced false speed limits in the speed zone database. The result was detection of false-positive high-range speeding. Through comparison of the service provider speed zone data against a second set of speed zone data, we were able to identify and eliminate data most affected by this systematic error, thereby establishing a data set of speeding events with a high level of sensitivity (a true positive rate of 92% or 6,412/6,960).

Conclusions: Mapped speed zones can be a source of error in real-world driving when examining vehicle speed. We explored the types of inaccuracies found within speed zone data and recommend that a second set of speed zone data be utilized when investigating speeding behavior or developing mapped speed zone data to minimize inaccuracy in estimates of speeding.     

Effects of speed humps on vehicle speed and pedestrian crashes in South Korea

Introduction: Speeding is a crucial risk factor for pedestrian safety because it shortens reaction time while increasing the impact force in collisions. Various types of traffic calming measures to prevent speeding have been devised. A speed hump—a raised bump installed in the pavement—has been widely used for this purpose. Method: To evaluate the effectiveness of speed humps, the speed profiles of vehicles passing speed humps were analyzed along with pedestrian crash records near speed humps. Results: The speed profiles showed that vehicles gradually diminished their speeds starting 30 m ahead of speed humps and, immediately after passing the humps, accelerated to regain their original speeds within a distance of 30 m. This speed reduction effect is substantial on both local and major roads: 18.4% and 24.0% reduction in speeds, respectively. The analysis of pedestrian crash records revealed that, inside the zones of speed reduction effect near speed humps (i.e., ±30 m from speed humps), fewer pedestrian crashes per roadway distance occurred and pedestrian injuries were less severe, compared with events outside the effect zones. This safety improvement was greater on major roads than local roads. Practical Applications: This work finds that the speed reductions that occurred near speed humps were gradual and influential ±30 m from their locations, suggesting that the hump installations should be close enough to the pedestrian crossings. It is noteworthy that, albeit that speed humps are more prevalent on local roads, the benefits of speed reduction effects from speed humps were more pronounced on major roads than on local roads. Therefore, speed humps on major roads can be considered a more effective measure for pedestrian safety.     

To speed or not to speed: Thematic analysis of American driving narratives

IntroductionSpeeding is a major cause of unintentional roadway death in the United States. Existing data show that U.S. drivers tend to speed less as they age, but reasons for this change remain largely unknown. Limited research has examined why U.S. drivers decide to speed or why U.S. drivers decide not to speed, and none to date has determined why speeding behaviors change over the life course. Research into these issues can provide insight that may be harnessed for more effective anti-speeding interventions that catalyze decisions not to speed. Methods: The current study asked a national sample of U.S. drivers (N = 309) about their driving behaviors and how they have changed over time using an open-ended prompt in an online survey. The authors qualitatively coded responses using a narrative analysis lens to identify common themes. Results: Results show U.S. drivers often make deliberate choices to speed and some do not consider speeding to be dangerous after achieving perceived mastery of driving skills. Participants tended to report speeding less over time, citing increased concern for family and other roadway users, which may help explain national speeding data trends. Several other themes emerged identifying individual cognitive factors, environmental contexts, and key persons impacting speeding decisions. Practical Applications: Findings show that the most effective means of encouraging U.S. drivers to decide not to speed may be multi-pronged intervention approaches highlighting how speeding reduces roadway driver control, connecting speeding with safety, and encompassing road design and law enforcement strategies.     

Consequences of raising the speed limit

Two methods were used to assess the potential impact of increased speed limits on highway fatalities. These were: (a) a method used by National Safety Council (NSC) in estimating the causes of decreased motor vehicles in the 1970s and (b) a method used by the National Research Council, Transportation Research Board (TRB) in reporting on 10 years of experience with the 55 mph speed limit. Applying the NSC method to 1984 fatality data resulted in estimated increases of 200 to 700 deaths per year on rural interstates depending on how much the speed limit was raised. Using the TRB method resulted in estimated increases of 300 to 450 deaths per year if each state returned to pre-1974 speed limits.     

Work domain analysis for air traffic controller weather displays

INTRODUCTION: Adverse weather conditions have a major impact on National Airspace System (NAS) operations. They create safety hazards for pilots, constrain the usable airspace for air traffic control (ATC), and reduce the overall capacity of the NAS. A system-wide dissemination of weather information to controllers could theoretically improve safety and efficiency. PROBLEM: However, it is currently unclear what weather information would be beneficial for tactical operations. Furthermore, no previous research has empirically evaluated optimal presentation designs for ATC weather displays. Ill-designed weather displays can cause safety hazards by presenting redundant information (i.e., by increasing the cognitive load) and display clutter (e.g., by interfering with the visual extraction of traffic data). METHOD: In the present paper, we outline our use of cognitive work analysis (CWA) techniques for the assessment of weather information needs for terminal controllers. RESULTS: Specifically, we describe how the CWA modeling tools helped us reveal instances in the terminal domain where weather information is lacking or insufficiently disseminated. We used our CWA results to drive the development of weather display concepts and to set up a high-fidelity simulation capability. IMPACT ON INDUSTRY: By means of high-fidelity simulations, we can empirically evaluate controller weather information needs in order to propose weather displays for increased aircraft safety and efficiency of terminal operations.     

Air bag effectiveness as function of impact speed

An investigation was conducted to estimate the effectiveness of air bags as a function of velocity. The study consisted of three parts: a theoretical idealization, an analysis of National Automotive Sampling System/Crashworthiness Data System (NASS/CDS), and a reanalysis of previously published Fatality Analysis Reporting System (FARS) data. The theoretical analysis looked at idealized risk curves as a function of velocity; assuming that the air bag offers a benefit for both belted and unbelted occupants. Analysis of the NASS/CDS data looked at the effectiveness of air bags as a function of velocity for Maximum Abbreviated Injury Scale (MAIS) 3+ injuries. The reanalysis of the previously published FARS data looked at the effectiveness of the air bag as a function of velocity for fatalities. The theoretical analysis indicates that the air bag effectiveness should be greatest at the low velocities. The field data analysis of both NASS/CDS and FARS were consistent with the theoretical analysis, indicating that air bags are most effective at the lower velocities, below 40 kph (25 mph), for both belted and unbelted occupants. Although it was not possible to estimate a different effect for belted and unbelted for fatalities using FARS, it was possible for MAIS 3+ using NASS/CDS. For unbelted occupants the effectiveness goes to zero or becomes negative above 40 kph (25 mph) for MAIS 3+, and for belted occupants the effectiveness stays positive but with significantly lower magnitude for speeds above 40 kph (25 mph).     

低速文丘里高效除尘器

文丘里除尘器的压力损失主要是高速气水混合射流通过喉管而造成的，通过喉管的压力损失与射流速度的平方成正比，低速文丘里高效除尘器，是根据液流的最优捕尘液粒粒径范围在100-800μm的范围来选定适当的喉管内气流和水滴的相对速度，而使这个相对速度选定为15-20m/s，这样使这一速度比普通文丘里除尘器的相对速度小（4-8倍）-（3-6倍），故通过喉管的压力损失至少小9倍，再加上混合射流与帽罩壁的碰撞和紧接着形成的帽罩侧壁孔的水幕的再次除尘使该除尘器的除尘效率达到97%以上。     

减速机齿轮表面探伤优化选择

采用模糊集的贴近度计算对齿轮表面探伤方法进行了优化选择,表明旋转磁场探伤是齿轮表面探伤的最佳方法,在实用中检测出大量的正在延伸扩展的表面疲劳裂纹.