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1.
某汽车在行驶过程中,其后轮毂轴在安装轴承附近发生断裂,该车累计行驶里程为17km,轮毂轴材料为65Mn弹簧钢。通过外观检查、断口宏微观观察、能谱分析、化学成分分析、硬度检测和金相检验等实验,确定了轮毂轴的失效性质及失效原因。结果表明:轮毂轴失效性质为疲劳断裂;轮毂轴内部存在锻造裂纹是轮毂轴发生疲劳断裂失效的主要原因;锻造裂纹的产生可能为切削量不足导致轮毂轴原材料料头端部存在块状缺陷。  相似文献   

2.
目的研究路灯灯管支架出现批量断裂失效的原因。方法通过化学成分分析、力学性能分析、断口扫描分析、金相组织分析、能谱分析等测试手段,对灯管支架的断裂模式及失效原因进行了分析。结果材料中存在贯穿性的带状硅、钙类非金属夹杂物,严重破坏了组织连续性;同时,晶界析出过多链状或断续网状三次渗碳体,导致了晶界脆性增大。结论材料内部缺陷会严重降低材料综合力学性能,通过对原材料冶炼工艺及后续热处理工艺进行改进,问题得到了有效解决,杜绝了此类失效事故再次发生。  相似文献   

3.
55CrSi弹簧钢失效分析与研究   总被引:1,自引:0,他引:1  
本文利用扫描电镜对弹簧钢的金相组织、断口及表面进行观察分析,研究其失效原因,结果表明此弹簧钢断裂为早期疲劳断裂,裂纹源萌生于并圈处,由于该处间隙过小,一则不能保证喷丸的效果,二则增加疲劳过程的接触疲劳应力及加重表面损伤,另外该处喷丸微细粒子未清洗干净,相当于表面有一夹杂在运行时遗留在并圈处表层,导致表面损伤,并诱发微裂纹而导致弹簧早期疲劳断裂。  相似文献   

4.
对某炼油厂的断裂活塞杆进行了失效分析。结果表明,活塞杆断裂为疲劳断裂,其显微组织中存在的严重魏氏组织缺陷和材料的硬度、强度值偏低是导致活塞杆断裂的原因。  相似文献   

5.
通过事故背景资料及封存车失效实物检查分析、显微组织、断口观察以及力学性能测定等方法,对小汽车左后摆臂断裂失效进行了系统分析.结果表明,摆臂材料存在铸造缺陷,组织缺陷、质量欠佳,以及不当的位置印字标记为造成摆臂疲劳断裂失效的主要原因.车速过大,急速摆向是导致翻车的直接原因.  相似文献   

6.
注塑机导柱使用约1a(年)即发生断裂失效。采用化学成分分析、显微组织观察、裂纹及断口特征分析等方法对注塑机导柱失效断裂的原因进行了综合分析。结果表明,导柱材料误用是造成导柱断裂的主要因素,导柱的断裂属于多源疲劳断裂。  相似文献   

7.
内燃机铸造铝合金活塞失效分析   总被引:2,自引:1,他引:1       下载免费PDF全文
通过化学成分分析、断口扫描分析及金相组织分析等手段,对内燃机铸造铝合金活塞顶部破裂失效原因进行了分析.结果表明,材料内部存在的组织缺陷及大量的铁相夹杂是导致构件早期失效断裂的主要原因.  相似文献   

8.
通过对高强度套管断裂原因进行大量调查研究和失效分析,认为套管材料钢级越高,需要匹配的韧性也越高,高强度(屈服强度≥140ksi,即965MPa)套管断裂原因主要与材料强度和韧性不匹配有关。要从根本上解决高强度套管断裂问题,首先应当对高强度套管断裂原因进行失效分析和研究,找出其断裂原因;然后依据失效分析和研究成果制定严格的订货技术标准,并采取一定的措施落实订货技术标准。  相似文献   

9.
通过宏观分析、扫描电镜及能谱分析、金相分析、化学成分分析、力学性能试验及受力分析等方法对卡箍连接片断裂失效原因进行了分析。结果表明:该卡箍连接片失效模式为高温蠕变断裂;导致其断裂的主要原因是装配条件下连接片承受的应力水平较高,在实际工作温度中存在较大的高温蠕变断裂风险;建议根据实际工况选用抗高温蠕变性能良好的材料。  相似文献   

10.
汽车钢板弹簧断裂失效分析   总被引:1,自引:1,他引:0  
采用金相及断口分析等方法,对早期疲劳断裂失效的汽车钢板弹簧进行了综合分析,得出,钢板弹簧产生疲劳断裂的主要原因是由于喷丸工艺控制不当,致使弹簧表面存在较多较多较深的弹坑,这些凹坑在弹簧工作时成为应力集中点而形成疲劳源,另上,弹簧表面局部区域存在脱碳,降低了材料的疲劳强度。  相似文献   

11.
BACKGROUND: Patient satisfaction and retention can be influenced by the development of an effective service recovery program that can identify complaints and remedy failure points in the service system. Patient complaints provide organizations with an opportunity to resolve unsatisfactory situations and to track complaint data for quality improvement purposes. SERVICE RECOVERY: Service recovery is an important and effective customer retention tool. One way an organization can ensure repeat business is by developing a strong customer service program that includes service recovery as an essential component. The concept of service recovery involves the service provider taking responsive action to "recover" lost or dissatisfied customers and convert them into satisfied customers. Service recovery has proven to be cost-effective in other service industries. THE COMPLAINT MANAGEMENT PROCESS: The complaint management process involves six steps that organizations can use to influence effective service recovery: (1) encourage complaints as a quality improvement tool; (2) establish a team of representatives to handle complaints; (3) resolve customer problems quickly and effectively; (4) develop a complaint database; (5) commit to identifying failure points in the service system; and (6) track trends and use information to improve service processes. SUMMARY AND CONCLUSIONS: Customer retention is enhanced when an organization can reclaim disgruntled patients through the development of effective service recovery programs. Health care organizations can become more customer oriented by taking advantage of the information provided by patient complaints, increasing patient satisfaction and retention in the process.  相似文献   

12.
The manufacturability of a cast product depends on process capabilities, which in turn depend on the facilities of the producer (foundry). Selecting the right combination of the product, process, and producer to simultaneously optimize functionality and manufacturability considerations is a challenging task. This paper presents a multi-criteria methodology that integrates the hitherto separate problems of process and producer selection, by introducing the concept of an ideal foundry. A set of 25 common criteria (11 objective and 14 subjective type) grouped under six headings (geometry, quality, production, delivery, facility, and other), have been identified to evaluate the process and the producer. Objective criteria are assessed using a fuzzy logic approach, whereas a rating method has been employed to accommodate subjective criteria. An analytical hierarchy process has been used to obtain the relative importance of the evaluation criteria. The methodology is also useful for benchmarking of foundries, and feedback for improving product–process compatibility. This is illustrated with an industrial example of a steel impeller casting.  相似文献   

13.
The optimisation of product infant failure rate is the most important and difficult task for continuous improvement in manufacturing; how to model the infant failure rate promptly and accurately of the complex electromechanical product in manufacturing is always a dilemma for manufacturers. Traditional methods of reliability analysis for the produced product usually rely on limited test data or field failures, the valuable information of quality variations from the manufacturing process has not been fully utilised. In this paper, a multilayered model structured by ‘part-level, component-level, system-level’ is presented to model the reliability in the form of infant failure rate by quantifying holistic quality variations from manufacturing process for electromechanical products. The mechanism through which the multilayered quality variations affect the infant failure rate is modelled analytically with a positive correlation structure. Furthermore, an integrated failure rate index is derived to model the reliability of electromechanical product in manufacturing by synthetically incorporating overall quality variations with Weibull distribution. A case study on a control board suffering from infant failures in batch production is performed. Results show that the proposed approach could be effective in assessing the infant failure rate and in diagnosing the effectiveness of quality control in manufacturing.  相似文献   

14.
Assembly process is a critical stage in the formation of product quality and reliability, but related consideration of the produced product reliability and accident risk has not attracted deserved attention in the most assembly quality analysis frameworks. To this end, this paper enhances risk analysis in assembly process quality control, which is advocated by ISO 9001:2015, and presents a risk-oriented assembly quality analysis approach considering the effects of assembly variations on the produced product reliability degradation and accident risk. First, a conceptual QRR chain is presented to illustrate the relationship among assembly process quality (Q), product reliability (R), and failure accident risk (R). Second, a risk-oriented and bidirectional framework for the analysis of assembly process quality is established based on the presented QRR chain aiming to quantitatively identify the risk sources in the assembly process and reduce the risk of failure accidents. Third, an assembly process quality risk model with key function reliability as its core is presented to establish the quantitative relationship between assembly variation and product failure accident risk. Finally, the presented approach is verified through a case study of an assembling quality risk analysing for acid-resistant grinder.  相似文献   

15.
Currently, many businesses in the consumer electronics industry are facing an increasing number of consumer complaints, despite the application of quality tools that proved to be very powerful in the past. We assessed over 20 new product development projects, to understand the reasons behind the rising number of consumer complaints. We found that businesses are developing more innovative products that are brought to the market faster, with inherently higher uncertainties on the consumer expectations of these products. Current analyses of consumer complaints solely focus on checking if the product is functioning according to the technical specification, and these analyses show a rising number of consumer complaints where no failure could be established. When looking at product quality and reliability from a consumer's perspective, we found that consumers complain not only about technical product failures but also when the product does not satisfy their expectations. In this paper we will take the perspective of the consumer to analyse dissatisfaction with new products from various available sources, which were not set‐up for quality and reliability purposes. We will show that analysing information from these sources gives better information, especially on the non‐technical failures compared with the traditional quality and reliability sources. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

16.
“质量管理”讲座(一)   总被引:2,自引:0,他引:2  
本讲座的主要目的是为质量管理工作的实施提供一些基础知识、内容包括:(1)质量的定义和重要性;(2)质量管理的组织;93)持续改善的过程和工具,包括PDCA和统计过程控制工具;(4)抽样检验,包括 随机取样、接收曲线和卖方、 买方风险;(5)产品设计工具,包括质量功能展开(质量屋)和田口方法的概念;(6)质量管理的国际标准,马尔科姆.鲍德里奇奖和戴明奖。  相似文献   

17.
本讲座的主要目的是为质量管理工作的实施提供一些基础知识,内容包括:(1)一的定义和重要性;(2)质量管理的组织;(3)持续改善的过程和工具,包括PDCA和统计过程控制工具,(4)抽样检验,包括随机取样,接收曲线和卖方,买方风险,(5)产品设计工具,包括质量功能展开(质量屋)和田口方法的概念,(6)质量管理的国际标准,马尔科姆.鲍德里奇奖和戴明奖。  相似文献   

18.
如果将生产过程中上一道工序的加工过程(设备)视为生产者,而紧邻的下一道工序的加工过程(设备)视为使用者,则上道工序加工的零部件在通过质量抽样检验进入下道工序的过程中.就将产生抽样风险。而由抽样风险确定的抽样方案直接关系到加工过程质量控制和检验成本控制等加工效率问题。考虑到许多大批量自动生产线的检验设备已经具备在线计算过程能力指数的能力.提出了一个基于过程能力指数的抽样风险分析方法,通过计算过程能力指数,得到相应的抽样风险.进而确定合理的抽样检验方案,从而将加工过程的重要指标——过程能力指数与抽样检验方案之间建立了联系。最后,以某汽车发动机曲轴生产线加工过程为例进行了抽样风险分析。  相似文献   

19.
“质量管理”讲座(三)   总被引:2,自引:0,他引:2  
本讲座的主要目的是为质量管理工作的实施提供一些基础知识 ,内容包括 :( 1)质量的定义和重要性 ;( 2 )质量管理的组织 ;( 3)持续改善的过程和工具 ,包括PDCA和统计过程控制工具 ;( 4 )抽样检验 ,包括随机取样、接收曲线和卖方、买方风险 ;( 5)产品设计工具 ,包括质量功能展开 (质量屋 )和田口方法的概念 ;( 6)质量管理的国际标准 ,马尔科姆·鲍德里奇奖和戴明奖。  相似文献   

20.
本讲座的主要目的是为质量管理工作的实施提供一些基础知识,内容包括(1)质量的定义和重要性;?(2)质量管理的组织;?(3)持续改善的过程和工具,包括PDCA和统计过程控制工具;?(4)抽样检验,包括随机取样、接收曲线和卖方、买方风险;?(5)产品设计工具,包括质量功能展开(质量屋)和田口方法的概念;?(6)质量管理的国际标准,马尔科姆*鲍德里奇奖和戴明奖.  相似文献   

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