Weibull_Reliability_Analysis 威布尔分布(韦伯分布)可靠性分析

Weibull分布（韦伯分布）(2006-07-04 22:04:01)转载分类：学习Weibull分布，又称韦伯分布、韦氏分布或威布尔分布，由瑞典物理学家Wallodi Weibull于1939年引进，是可靠性分析及寿命检验的理论基础。

Weibull分布能被应用于很多形式，包括1参数、2参数、3参数或混合Weibull。

3参数的该分布由形状、尺度（范围）和位置三个参数决定。

其中形状参数是最重要的参数，决定分布密度曲线的基本形状，尺度参数起放大或缩小曲线的作用，但不影响分布的形状。

另外，通过改变形状参数可以表示不同阶段的失效情况；也可以作为许多其他分布的近似，如，可将形状参数设为合适的值近似正态、对数正态、指数等分布。

形状参数通常在[1，7]间取值。

一般由W（α,β）表示2个参数的Weibull分布，其分布函数为：，其中x>0，α、β>0。

可以看出有两个参数α、β，其中β为形状参数，α为尺度参数。

若取β为1，则F（x）为指数分布。

Weibull分布的概率密度函数（pdf）为：。

Weibull双参数的PDF分布见上图。

（自己做的，有点粗糙）下面我们以其pdf图看Weibull分布各参数的作用。

下图是形状参数β对pdf的影响（α固定）：下图为尺度参数α对pdf的影响（β固定），横轴为变量x，纵轴为f（x）：另外，由于Weibull分布可以近似表示其他别的分布，eg，β=1时，F（x）为指数分布。

将其用到复杂网络中，则此时对应指数网络？当β逐渐增大时，是不是对应分布极不均匀的无尺度网络？这样的话可以通过调整一个参数构造不同的网络？而**人的层次故障节点动态模型就是因此而引入Weibull分布（1参数）的吧？这样的话，β大的网络发生层次故障的规模比较大就可以理解了。

再继续深入分析。

六西格玛培训—验证阶段模块可靠性分析Patrick ZhaoI&CIM Deployment Champion可靠性分析介绍执行可靠性分析可靠性分析介绍执行可靠性分析可靠性与质量•狭义的质量，一般指的是符合性质量，即是否满足标准或规范，通常是以产品出厂时的状态为准，此时传统的质量控制人员已经完成任务。

•可靠性更多关注在产品的全生命周期中的质量表现，即产品是否能够始终满足标准，始终满足客户的应用。

在如今全面质量管理的阶段，产品的可靠性也越来越需要企业投入更多的时间。

•企业中的可靠性分析可以分为产品和过程：•产品：分析产品在客户使用中是否满足可靠性目标。

•过程：一般指设备、工装、模具等在长期使用过程中，是否会出现问题。

可靠性工程的益处•在物质匮乏的年代，衣服可能是作为耐用品使用，而如今衣服已经越来越成为快速消费品。

曾经的手机等电子产品，更换周期也同样有越来越短的趋势。

甚至是汽车也开始加速迭代，不停缩短换车的时间。

•在这样的背景下，可靠性似乎成为了一个不是那么重要的关注点，可是为什么我们仍然在关注可靠性工程？•政府、法规的要求。

•不可靠的产品通常有安全或健康风险。

•产品变得复杂，零件变多，更容易发生故障。

•可靠性的优势可以成为销售和市场部门的宣传点。

•处于保护环境，节约资源的考虑。

可靠性分析的常用术语•浴缸曲线（Bathtub Curve）•MTTF: Mean Time To Failure（平均失效前时间）•MTTR: Mean Time To Repair（平均修复时间）•MTBF: Mean Time Between Failure（平均故障发生间隔时间）•威布尔分布（Weibull Distribution）•数据删失（Data Censoring）•HALT: Highly Accelerated Life Testing（高加速寿命试验）•HASS: Highly Accelerated Stress Screening（高加速应力筛选）•HASA: Highly Accelerated Stress Audit（高加速应力稽核/抽检）浴缸曲线•浴缸曲线（Bathtub Curve）在可靠性分析中是一种常用的概念，它把失效分为三个阶段。

基于非线性最小二乘法的威布尔分布参数估计摘要：针对传统威布尔参数估计方法对于初值要求较高且精度不高的问题，提出了非线性最小二乘法参数估计算法。

首先介绍三参数威布尔分布的函数形式；然后阐述了非线性最小二乘法的基本原理；最后采用某机构液压锁寿命数据作为算例验证本文方法，算例表明基于最小二乘法的威布尔分布参数估计精度较高，具有一定的工程应用价值。

关键字：威布尔分布非线性最小二乘法参数估计前言瑞典科学家W.Weibull根据两参数威布尔分布构建了而三参数威布尔（Weibull）分布。

在估计三参数Weibull分布参数时，现在最常用的方法包括图解法、极大似然法、最小二乘法、线性回归估计法等[3]。

其中，图解法操作简单，但估计值精度不高；后三种解析法在样本量较大时，其估计效果较好，但在当拟合的函数为非线性函数时，估计精度将大为下降，从而使得这三种算法面对非线性函数拟合时失去应用价值。

为此本文引进非线性最小二乘算法。

非线性最小二乘算法非常适合解决非线性函数的参数估计问题。

非线性最小二乘法通过特定的变换方法，将非线性问题转换为线性问题；再得到线性函数估计值后，再根据转换关系式将其转换为非线性函数的估计值。

以某机构液压锁寿命为算例，结果表明非线性最小二乘法参数估计精度较高，具有一定的工程应用价值。

1威布尔分布简介三参数Weibull分布是一种比较完善的分布，在拟合随机数据方面十分灵活，适应性很强。

因此，三参数Weibull分布能更准确地描述疲劳寿命的概率分布，而且，在可靠性研究领域中的几种常用分布，如指数分布、瑞利分布等都可看作是三参数Weibull分布的特例。

若随机变量X服从三参数威布尔分布，则其概率密度函数为：其中，为Gamma函数。

2 非线性最小二乘法当模型中拟合参数与被拟合数据之间呈现为非线性函数关系时，就形成非线性拟合。

非线性拟合较难处理，有时甚至连解的存在性和唯一性都难以确定。

有些非线性拟合，在通过对拟合参数或/和原始数据的适当函数变换后，能使“变换后拟合参数”与“变换后原始数据”之间的关系呈现为线性形式；则称这种非线性拟合是“非本质的非线性”；而这种变换处理方式称为“伪线性化”。

招聘可靠度工程师笔试题与参考答案(某世界500强集团)(答案在后面)一、单项选择题（本大题有10小题，每小题2分，共20分）1、可靠度工程师在进行产品寿命预测时，通常使用以下哪种方法？A、蒙特卡洛模拟B、线性回归分析C、时间序列分析D、神经网络分析2、在可靠性试验中，以下哪个参数是用来描述产品失效时间的？A、平均故障间隔时间（MTBF）B、平均修复时间（MTTR）C、故障率（FR）D、失效率（λ）3、在可靠性工程中，以下哪个指标可以用来评估产品在特定时间内发生故障的概率？A. 平均无故障时间（MTBF）B. 平均故障间隔时间（MTTF）C. 失效率（λ）D. 平均修复时间（MTTR）4、以下哪个选项是可靠性增长的典型曲线？A. S形曲线B. 对数正态分布曲线C. 贝塔分布曲线D. 指数分布曲线5、在可靠性工程中，以下哪个指标是用来衡量产品在规定时间内，完成规定功能的概率？A. 平均无故障时间（MTBF）B. 可靠度（R(t)）C. 失效率（λ）D. 浴盆曲线6、以下哪种方法常用于评估产品的可靠性设计是否满足要求？A. 故障树分析（FTA）B. 有限元分析（FEA）C. 质量控制图（QC图）D. 六西格玛分析7、在可靠性工程中，MTBF（平均故障间隔时间）指的是什么？A. 设备从首次使用到发生第一次故障的时间B. 设备在两次连续故障之间的平均运行时间C. 设备修复并重新投入使用的时间D. 设备完全失效后不再修复的时间8、在进行可靠性分析时，哪种分布常用于描述电子产品或机械产品的故障率？A. 正态分布B. 泊松分布C. 指数分布D. 威布尔分布9、在软件可靠度评估中，以下哪个指标通常用于衡量系统在特定时间内发生故障的概率？（）A、可靠性增长率B、平均故障间隔时间（MTBF）C、故障率D、平均修复时间（MTTR） 10、在软件可靠性增长模型中，以下哪个模型假设软件缺陷的分布是指数分布的？（）A、Weibull模型B、泊松模型C、Gamma模型D、Lognormal模型二、多项选择题（本大题有10小题，每小题4分，共40分）1、以下哪些因素会影响可靠度工程师在评估产品可靠性时所采用的故障模式与影响分析（FMEA）的准确性？（）A、故障模式识别的全面性B、故障原因分析的正确性C、潜在影响评估的准确性D、预防措施的有效性E、风险评估的客观性2、在可靠性设计中，以下哪些方法可以提高产品的可靠性？（）A、冗余设计B、热设计C、故障安全设计D、环境适应性设计E、标准化设计3、在可靠性工程中，故障模式及影响分析（FMEA）的主要目的是什么？（多选）A. 分析系统可能的故障模式B. 确定每个故障模式对系统的影响C. 提供一种方法来降低产品成本D. 评估现有控制措施的有效性E. 识别并优先处理潜在的设计缺陷4、关于可靠性指标MTBF（平均无故障时间）和MTTR（平均修复时间），下列说法哪些是正确的？（多选）A. MTBF是指设备从一次故障恢复到下一次故障发生的时间间隔B. 较高的MTBF值意味着更好的系统可靠性C. MTTR指的是从故障发生到完全恢复正常运行所需的时间D. 较低的MTTR值表示更快速有效的维护响应E. 在评估系统可靠性时，仅考虑MTBF而不考虑MTTR是充分的5、以下哪些是可靠度工程师在工作中需要掌握的软件工具？（）A. MATLABB. SPSSC. ANSYSD. SolidWorksE. Excel6、以下关于可靠性试验的说法，正确的是？（）A. 可靠性试验分为环境应力筛选试验和寿命试验B. 环境应力筛选试验的目的是检测产品在特定环境下的可靠性C. 寿命试验的目的是确定产品的失效寿命分布D. 可靠性试验通常需要在实验室进行E. 可靠性试验结果可以用于制定产品的质量标准7、以下哪些因素会影响可靠度工程师在产品寿命周期内的任务重点？（）A. 产品设计阶段B. 产品制造阶段C. 产品使用阶段D. 产品维护阶段E. 产品回收阶段8、以下关于可靠性试验的描述，正确的是哪些？（）A. 可靠性试验是评估产品可靠性的主要方法之一。

威布尔分布如何根据形状参数,尺度参数,截距等拟合公
式
威布尔分布是一种概率分布，广泛用于寿命测试和可靠性工程。

它是由形状参数（k）、尺度参数（η）和截距（T）确定的。

以下是根据给定的参数来描述威布尔分布的公式：
1. 概率密度函数（PDF）：
\(f(t) = \frac{k}{\eta} \left( \frac{t}{\eta} \right)^{k-1} e^{-
\left( \frac{t}{\eta} \right)^k}\)
其中，\(t\) 是观察的时间，\(k\) 是形状参数，\(\eta\) 是尺度参数。

2. 累积分布函数（CDF）：
\(F(t) = 1 - e^{- \left( \frac{t}{\eta} \right)^k}\)
其中，\(t\) 是观察的时间，\(k\) 是形状参数，\(\eta\) 是尺度参数。

3. 均值（期望值）：
\(\mu = \eta \Gamma(1+1/k)\)
其中，\(\Gamma\) 是伽玛函数。

4. 方差：
\(\sigma^2 = \eta^2 \left[ \Gamma(1+2/k) - \Gamma^2(1+1/k)
\right]\)
其中，\(\Gamma\) 是伽玛函数。

这些公式可以根据给定的参数（形状参数、尺度参数和截距）进行拟合。

在实践中，通常会使用最大似然估计法（MLE）或其它统计方法来估计这些参数。

韋伯分佈韋伯分佈(Weibull distribution)以指數分佈為一特例。

其p.d.f.為其中α,β>0。

以表此分佈, 有二參數α,β, α為尺度參數, β為形狀參數。

若取β=1, 則得分佈, 以表之。

底下給出一些韋伯分佈p.d.f.之圖形。

韋伯分佈是瑞典物理學家Waloddi Weibull, 為發展強化材料的理論, 於西元1939年所引進, 是一較新的分佈。

在可靠度理論及有關壽命檢定問題裡, 常少不了韋伯分佈的影子。

分佈的分佈函數為期望值與變異數分別為Characteristic Effects of the Shape Parameter, β, for the Weibull DistributionThe Weibull shape parameter, β, is also known as the slope. This is because the value of β is equal to the slope of the regressed line in a probability plot. Different values of the shape parameter can have marked effects on the behavior of the distribution. In fact, some values of the shape parameter will cause the distribution equations to reduce to those of other distributions. For example, when β = 1, the pdf of the three-parameter Weibull reduces to that of the two-parameter exponential distribution or:where failure rate.The parameter β is a pure number, i.e. it is dimensionless.The Effect of β on the pdfFigure 6-1 shows the effect of different values of the shape parameter, β, on the shape of the pdf. One can see that the shape of the pdf can take on a variety of forms based on the value of β.Figure 6-1: The effect of the Weibull shape parameter on the pdf.For 0 < β1:∙As (or γ),∙As , .∙f(T) decreases monotonically and is convex as T increases beyond the value of γ.∙The mode is non-existent.For β > 1:∙f(T) = 0 at T = 0 (or γ).∙f(T) increases as (the mode) and decreases thereafter.∙For β < 2.6 the Weibull pdf is positively skewed (has a right tail), for 2.6 < β < 3.7 its coefficient of skewness approaches zero (no tail). Consequently, it may approximatethe normal pdf, and for β > 3.7 it is negatively skewed (left tail).The way the value of β relates to the physical behavior of the items being modeled becomes more apparent when we observe how its different values affect the reliability and f ailure ratefunctions. Note that for β = 0.999, f(0) = , but for β = 1.001, f(0) = 0. This abrupt shift is what complicates MLE estimation when β is close to one.The Effect ofβ on the cdf and Reliability FunctionFigure 6-2: Effect of β on the cdf on a Weibull probability plot with a fixed value of η.Figure 6-2 shows the effect of the value of β on the cdf, as manifested in the Weibull probability plot. It is easy to see why this parameter is sometimes referred to as the slope. Note that the models represented by the three lines all have the same value of η. Figure 6-3 shows the effects of these varied values of β on the reliability plot, which is a linear analog of the probability plot.Figure 6-3: The effect of values of β on the Weibull reliability plot.∙R(T) decreases sharply and monotonically for 0 < β < 1 and is convex.∙For β = 1, R(T) decreases monotonically but less sharply than for 0 < β < 1 and is convex.∙For β > 1, R(T) decreases as T increases. As wear-out sets in, the curve goes through an inflection point and decreases sharply.The Effect of β on the Weibull Failure Rate FunctionThe value of β has a marked effect on the failure rate of the Weibull distribution and inferences can be drawn about a population's failure characteristics just by considering whether the value of β is less than, equal to, or greater than one.Figure 6-4: The effect of β on the Weibull failure rate function.As indicated by Figure 6-4, populations with β < 1 exhibit a failure rate that decreases with time, populations with β = 1 have a constant failure rate (consistent with the exponential distribution)and populations with β > 1 have a failure rate that increases with time. All three life stages of the bathtub curve can be modeled with the Weibull distribution and varying values of β.The Weibull failure rate for 0 < β < 1 is unbounded at T = 0 (or γ). The failure rate, λ(T), decreases thereafter monotonically and is convex, approaching the value of zero asor λ( ) = 0. This behavior makes it suitable for representing the failure rate of units exhibiting early-type failures, for which the failure rate decreases with age.When encountering such behavior in a manufactured product, it may be indicative of problems in the production process, inadequate burn-in, substandard parts and components, or problems with packaging and shipping.For β = 1, λ(T) yields a constant value of or:This makes it suitable for representing the failure rate of chance-type failures and the useful life period failure rate of units.For β > 1, λ(T) increases as T increases and becomes suitable for representing the failure rate of units exhibiting wear-out type failures. For 1 < β < 2, the λ(T) curve is concave, consequently the failure rate increases at a decreasing rate as T increases.For β = 2 there emerges a straight line relationship between λ(T) and T, starting at a value ofλ(T) = 0 at T = γ, and increasing thereafter with a slope of . Consequently, the failurerate increases at a constant rate as T increases. Furthermore, if η = 1 the slope becomes equal to 2, and when γ = 0, λ(T) becomes a straight line which passes through the origin with a slope of 2. Note that at β = 2, the Weibull distribution equations reduce to that of the Rayleigh distribution.When β > 2, the λ(T) curve is convex, with its slope increasing as T increases. Consequently, the failure rate increases at an increasing rate as T increases indicating wear-out life.TopCharacteristic Effects of the Scale Parameter, η, for the Weibull DistributionFigure 6-5: The effects of η on the Weibull pdf for a common β.A change in the scale parameter η has the same effect on the distribution as a change of the abscissa scale. Increasing the value of η while holding β constant has the effect of stretching out the pdf. Since the area under a pdf curve is a constant value of one, the "peak" of the pdf curve will also decrease with the increase of η, as indicated in Figure 6-5.∙If η is increased while β and γ are kept the same, the distribution gets stretched out to the right and its height decreases, while maintaining its shape and location.∙If η is decreased while β and γ are kept the same, the distribution gets pushed in towards the left (i.e. towards its beginning or towards 0 or γ), and its height increases.η has the same units as T, such as hours, miles, cycles, actuations, etc.TopCharacteristic Effects of the Location Parameter, γ, for the Weibull DistributionThe location parameter, γ, as the name implies, locates the distribution along the abscissa. Changing the value of γ has the effect of "sliding" the distribution and its associated function either to the right (if γ > 0) or to the left (if γ < 0).Figure 6-6: The effect of a positive location parameter, γ, on the position of the Weibullpdf.∙When γ = 0, the distribution starts at T = 0 or at the origin.∙If γ > 0, the distribution starts at the location γ to the right of the origin.∙If γ < 0, the distribution starts at the location γ to the left of the origin.∙γ provides an estimate of the earliest time-to-failure of such units.∙The life period 0 to +γ is a failure free operating period of such units.∙The parameter γ may assume all values and provides an estimate of the earliest timea failure may be observed. A negative γ may indicate that failures have occurred priorto the beginning of the test, namely during production, in storage, in transit, duringcheckout prior to the start of a mission, or prior to actual use.∙γ has the same units as T, such as hours, miles, cycles, actuations, etc.。

基于Weibull分布计算在造船设备故障发生概率统计中的应用摘要：造船设备故障发生过程大多遵循一定的客观规律，所以，利用Weibull分布计算对造船设备故障发生概率进行统计，可为造船设备保养与维修提供有效的参考依据。

因此，利用Weibull分布计算，针对造船设备故障的发生规律进行分析，可对设备的可靠度以及故障率等进行计算，对造船设备的维修管理水平提升有促进作用。

关键词：Weibull分布计算；造船设备；故障；概率统计引言：造船设备故障维修包含预防性维修以及故障后维修两种方式，在对造船设备故障进行分析维修过程中，要针对造船设备不同故障的发生概率进行统计与分析，这对保证造船设备的实际应用水平方面有促进作用。

在利用Weibull分布计算的视角下，造船设备故障发生概率统计与分析，以浙江舟山启明电力集团公司的造船设备为研究对象，针对造船生产过程中的关键设备故障发生概率进行统计，对保障生产有现实意义[1]。

1Weibull分布计算逻辑分析Weibull分布计算又名威布尔分布计算，可通过浴盆失效概率曲线的各个阶段对不同故障发生概率进行统计，可提高故障概率分析的准确性及有效性[2]。

设备某一局部失效或者局部故障导致设备停运可服从Weibull分布。

在进行Weibull分布计算中，故障发生概率计算公式如下：在上述公式中，β为形状参数，为尺度参数，β<1，则属于设备的早期故障，β>1则属于耗损故障，β=1为偶发故障。

在对可靠度进行计算与分析中，表示固定条件下，固定时间内完成规定的发生概率。

故障率则是在时间t与t时间点之前发生的概率，可通过可靠度以及故障率的计算，对造船设备发生故障的概率进行统计与分析，为设备故障维修及管理等提供参考依据[3]。

2Weibull分布计算在造船设备故障发生概率统计中的应用2.1案例分析结合浙江舟山启明电力集团公司造船设备故障类型，对不同故障发生概率进行统计与分析。

根据造船设备维修台账，对设备正常运行时间、设备维修时间的分布进行统计与分析。

10分布参数体系分布参数体系是概率统计学中的一个重要概念，用于描述随机变量的分布情况。

它包括了多种常见的概率分布，每个分布都有自己的参数来描述它的特征。

下面我将介绍十种常见的分布参数体系。

1. 正态分布（Normal distribution）是最常见的分布之一，它的参数是均值μ和标准差σ。

正态分布是一个对称的钟形曲线，大部分数据点集中在均值附近，标准差越小，曲线越窄。

2. 二项分布（Binomial distribution）描述了重复n次的独立的二元试验中成功的次数。

它的参数是试验次数n和成功的概率p。

4. 几何分布（Geometric distribution）描述了在一系列独立的伯努利试验直到首次成功之间所需的试验次数。

它的参数是成功的概率p。

5. 负二项分布（Negative binomial distribution）描述了在一系列独立的伯努利试验中直到r次成功所需的试验次数。

它的参数是成功的概率p和成功的次数r。

6. 均匀分布（Uniform distribution）描述了一个随机变量在一个有限的区间上取值的概率是相等的。

它的参数是最小值a和最大值b。

9. 威布尔分布（Weibull distribution）是一种常用的可靠性分布，用于描述时间到达或设备故障的概率。

它的参数是形状参数k和尺度参数λ。

10. 贝塔分布（Beta distribution）是用于描述在一个有限区间内的概率分布，例如概率或比例。

它的参数是两个形状参数α和β。

这些分布参数体系是概率统计学中最常见的分布，它们在不同领域的数据分析和建模中发挥了重要的作用。

通过确定合适的参数值，我们可以根据这些分布来描述和预测随机变量的行为。

这对于决策和风险评估非常重要。

Weibull分布（韦伯分布、威布尔分布）
log函数
从概率论和统计学⾓度看，Weibull Distribution是连续性的概率分布，其概率密度为：
其中，x是随机变量，λ＞0是⽐例参数（scale parameter），k＞0是形状参数（shape parameter）。

显然，它的累积分布函数是扩展的指数分布函数，⽽且，Weibull distribution与很多分布都有关系。

如，当k=1，它是指数分布；k=2时，是Rayleigh distribution(瑞利分布)。

Weibull概率密度函数
k <1的值表⽰故障率随时间减⼩。

如果存在显着的“婴⼉死亡率”或有缺陷的物品早期失效，并且随着缺陷物品被除去群体，故障率随时间降低，则发⽣这种情况。

在创新扩散的背景下，这意味着负⾯的⼝碑：危险功能是采⽤者⽐例的单调递减函数;
k = 1的值表⽰故障率随时间是恒定的。

这可能表明随机外部事件正在导致死亡或失败。

威布尔分布减⼩到指数分布;
k> 1的值表⽰故障率随时间增加。

如果存在“⽼化”过程，或者随着时间的推移更可能失败的部分，就会发⽣这种情况。

在创新扩散的背景下，这意味着积极的⼝碑：危险功能是采⽤者⽐例的单调递增函数。

该函数⾸先是凹的，然后是凸的，拐点为
Weibull累计分布函数。

概率（儿率）probability•方差variance•分散维修decentralized maintenance•动态试验dynamic test•动力设备设施管理power facilities management•除尘、防护设备管理duct-proof and protective equipme nt man agemen t •抽样调查sampling investigation•备件国产化管理domestic production management of imported spare parts •标准偏差standard deviation•安装预算budget of installation•包机制machine contract!ng system•班前检查与润滑制度regulation of check and lubrication before on shift •［设备］交接班制度shift relief system•《设备管理条例》（《条例》）《Equipment Management Regulation》•［设备］修理repair•［设备］维修maintenance （and repair）•重点调查key-point investigation•重点设备管理management of key-point equipment•重点设备key-point equipment•责任事故liability accident•指数分布exponential distribution•直方图histogram•预付与托收承付prepayment and collection•预防性试验prophylactic test•预防为主prevention first•正交设讣法（正交试验法）orthogonal design•正态分布normal distribution•运输车辆管理制度transportation vehicle management system•质量“三包M three guarantees of quality•质量事故accident due to quality•丿E力容器管理制度management regulation of pressure vessel•无故障运行时间mean time to failure•威布尔分布Weibull distribution•闲置设备管理制度idle equipment management•闲置设备idle plant•统计分析statistical analysis•维修性maintainability•维修信息管理maintenanee information management•维护与il•划检修相结合combination of service and planned maintenance •随机事件random event•数控设备管理numerical control （NC） equipment management•三级保养制three-level service system•数学期望mathematical expectation•数学模型mathematical model•数理统计mathematical statistics•生产技术装备technical facilities in production•生产设备production equipment•寿命周期希用life cycle cost (LCC)•润滑油库管理制度mangement regulation of lubricant warehouse•商检(商品检验)commodity inspection•设汁、制造与使用相结合combination of design, manufacturing and operation •设备调研investigation on plant•设备的可靠性与可靠度reliability reliability theory•设备的节能性energy saving property of plant•设备的检查i平比facility inspection and appraise through comparison for plant •设备点检制度plant check system•设备的成套性complete set of plant•设备的安全性safety of plant•设备的生产率productivity of plant设备的耐用性durability of plant•设备的灵活性flexibility of plant•设备状态监测与诊断技术管理equipment condition monitoring and diagnostic tech no logy manage•设备状态管理制度equipment condition management systen•设备综合管理total plant management•设备资产动态管理制度dynamic management system of plant assets•设备租赁plant leasing•设备修前准备制度preparation system before equipment repair•设备修理工时定额man-hours quota for equipment repair•设备修理费用定额expense quota for equipment repair•设备修理材料定额material quota for equipment repair•设备修理质量验收制度acceptance regulation of equipment repair quality•设备型号equipment model•设备型式type of equipment•设备经济寿命economical life of equipment•设备经营管理制度operation and business management system•设备技术档案technical document of plant•设备技术状况technical conditions of equipment•设备技术状态管理technical condition management of plant•设备技术资料管理制度management system for technical document and plant •设备技术性能technical properties of plant•设备技术寿命technical life of equipment•设备检修专业化协作specialized cooperation of plant maintenance•设备检修讣划管理制度planning and management regulation of plantmain tenance•设备检修计划plant maintenance plan•设备检修规程plant maintenance specification•设备检修质量plant maintenance quality•设备基设讣与施工design and construction of equipment foundation•设备合同管理management of equipment order contract•设备规划可行性分析feasibility studies of plant project设备规划investment plan of plant•设备功能（效能）performance of plant•设备工作能力operational capability of plant•设备管理考核制度exami nation and check systems of plant man agement•设备管理经济责任制度economic responsibility regulation of plant management •设备管理岗位标准post standard of plant management•设备管理制度plant management systems•设备管理停歇时间定额（停歇天数）downtime quota for equipment repair•设备管理现代化plant engineering modernization•设备管理plant management, plant enginerring•设备固定资产管理制度fixed plant assets management systems•设备故障equipment failure•设备更新管理前度plant renewal management•设备更新plant renewal•设备更换plant replacement•设备岗位责任post responsibility of plant management•设备改造管理制度equipment modification management system•设备改造plant reconstruction, plant modernization•设备分级管理classified management of plant•设备定人定机、凭证操作规定operation regulation with fixed qualified operator and fixed eq•设备操作的"五项纪律” "five disciplines"of plant operation•设备操作规程operation specification of equipment•设备备品配件管理制度management regulation of equipment spare parts•设备备件库房管理制度management regulation of equipment spare partsinv entory•设备报价to quote plant price•设备报废discard of plant•设备安装管理equipment installation management•设备安装equipment installation•设备巡回检查制度tours system to inspect plant•设备询价to enquire plant price设备选型plant model selection•设备验收交接制度acceptance check and reception systems of plant•设备统计报表制度statistic-reporting system of plant•设备维修技术资料technical document and date for plant maintenance•设备维修技术管理制度management regulation of plant maintenance technology •设备维修定额equipment maintenance quota•设备维护规程equipment service specification•设备台帐unit account of plant•设备完好标准equipment perfectness norm•设备完好plant in good condition•设备索赔claims for equipment•设备使用规程specifications of usage•设备使用初期信息反馈管理information feedback management in initial operation period of pl•设备使用与维护管理制度management regulation for operation and service of equipment•设也全过程管理life-cycle management of plant•设备寿命life of equipment•设备润滑管理制度lubrication management regulation of plant•设备润滑“五定” "five fixation^^ of lubricatio n•设备事故管理制度accident management regulation of plant•设备事故"三不放过M three do not let pass of plant accident•设备事故plant accident•设备区域维修负责制region responsibility system of plant maintenance•设备前期管理和后期管理fore period and later period management of plant•设备前期管理规定regulation of fore period management of plant•设备磨损补偿wear compensation for plant•设备老化plant ageing•算术平均值（均值）arithmetic mean•强制保养制coercionary service system•投资效果系数effect coefficient of investment•设备经济管理制度economic management system of plant设备管理i平优》舌动excellence selection activity in plant management•排列图（帕累托图）Pareto chart•负荷试验load test•故障停机时间breakdown time•工艺适应性technological adaptability•工程设备监理supervision of engineering facilities•工序控制点设备管理management of proccess-control-point equipment•合同变更与解除contract change and cancellation•混合维修combined maintenance•回归分析regression analysis•检査间隔期interval between inspections•检修社会化socialization of maintenance•集中维修centralized maintenance•技术先进性technical advancement•技术管理与经济管理相结合combination of technical management and economic man agement•计算机辅助设备管理computer-aided plant management•计划预修制度（J1T1P） planned preventive maintenance system•进口设备离岸价FOB of imported equipment•进口设备管理imported equipment management•进口设备到岸价CIF of imported equipment•精、大、稀设备precise,large scale,rare plant•精、大、稀设备管理management of precise,large scale,rare equipment •精、大、稀、关键设备的"五定""five fixed” of precise,large scale,rare,critical equipme•经济性economy•静态试验static test•开箱检查opervcase inspect!on•平均偏差average deviation•平均等待时间mean waiting time,MWT•修理周期repair cycle•修理周期结衣I structure of repair cycle修理、改造与更新相结合combination of repair, modernization and renewal•修理复杂系数complexity coefficient of repair•修理间隔期time between repairs•租赁设备管理制度leased equipment management system•资金的时间价值time value of fund•自然事故natural accident•自制设备self-made equipment•自制设备管理制度management system for selfmade equipment•自制备件管理制度self-made spare parts management system•专业管理与群众管理相结合combination of professional management and mass man agement•转让设备(设备调剂)transfer of facility•典型调查typical investigation•地区(部门)修理中心areal (departmental) repair center•废油回收率recovery ratio of used oil•动力设备完好率perfectness ratio of power plant•定期保养完成率fulfillment ratio of periodic service•大修理平均停歇天数mean downtime(days) due to overhaul•重点设备完好率perfectness ratio of key-point equipments•一次交验合格率qualification ratio under first acceptanee check•在用设备可利用華availability of plant in use•已安装设备利用率utilization ratio of installed equipments•万元固定资产年创利润率annual profit ratio per 10000 yuan fixed assets•万元产值占用维修费用maintenance expense for 1000 yuan production value •实有设备安装率installation ratio of owned equipments•设备综合利用率comprehensive utilization ratio of plant•设备资产增值率added value rate of plant assets•设备资产投资回收期capital investment recovery period of plant•设备新度newness degree of plant•设备净资产创利润率profit ratio vs net book value of plant•设备计划台时利用率utilization ratio of planned time of plant设备构成比constitution ratio of plant•设备负荷率load rate of plant•设备返修率back repair rate•设备制度台时利用毎utilization ratio of institutional time of plant•设备闲置率idelness ratio of plant•设备投资回收报率plant capital investment recovery ratio•设备投资产出比capital investment recovery period of plant•设备完好率perfectness ratio of plant•设备日常保余完成率plant daily service fulfillment ratio•设备事故频率incident frequency•设备利用率utilization ratio•事故［故障］停机率down time ratio to accident (failure)•清洗换油计划完成率fulfillment ratio of cleaning and oil change plan•每个修理复杂系数平均大修理成本mean repair cost per complexity coefficient of repair•每个复杂系数占用维修费用maintenance expense per repair complexity coefficie nt•每万元固定资产创工业增加值率industrial increase value ratio per 10000 yuan fixed assets•故障强度failure intensity•故障频率failure frequency•关键设备完女子率perfectness ratio of critical equipments•精大稀设备完好率perfectness raito of precise,large scale and rare equipments •可利用率(有效利用率)availability•平均停机时间mean down time,MDT•平均故障间隔期，平均无故障丄作时间mean time between failture•修理计划完成率fulfillment ratio of repair plan废润滑油再生(废油再生)regeneration of waste lubricating oil•防泄漏管理leak prevention management•二级保养second level service•定期精度调整periodic accuracy adjustment•定人定机制度system of fixed machine and operator•额定载荷rated load•超负荷试运行commissioning under overload•初步试运行preliminary commissioning•操作工人的"四会"four basic skills for operator•参数故障parametric failure•保养计划完成率fulfilment ratio of service plan•保养规程service specification•保养"十字"作业法"ten words" method for service•保养service•安全性故障safety failure•安全规程safety procedure•［设备性能］劣化degradation (of equipment performance)•PM 小组PM group•隐蔽故障hidden failure•有效性availability•有效度availability•有效寿命effective life•制度时间institutional time•—级保养first level service•原发故障primary failure•原始记录original record•正常负荷normal load•正常超载normal overload•治漏"八字"法"eight words" method for leakage control•运亍时T可operating time仪表"三率” "three rate M of meter•早（初）期故障期early failure period•永久性故障（持续性故障）permanent failure•验收试运行fin al commissioning•无泄露［区］标准leakless（area） standard•突发性（偶发）故障random failure•维护费service cost•危险性故障dangerous failure•误操作故障failure by misoperation•完好设备perfect facility•生产维修productive maintenance（PM）•润滑工作岗位责任制post responsibility of lubrication work•润滑管理制度lubrication management system•润滑"五定M"five fixation" of lubrication•润滑“三过滤H three-step filtration of lubricating oil•润滑站lubricating station*1闰滑图表lubricating diagram•试车commissioning•日常保养费daily service expenses•日常保养（日保）daily service•日历时间利用率utilzation ratio of calender time•设备的可靠性和可靠度reliability•设备的区域维护regional service of equipment•设备技术状态technical conditions of equipment•设备故障率曲线（浴盆曲线）failure rate curve of equipment,tub curve •设备操作合格证operation licence•设备"5S”活动"5S” activity of equipment•设备隐患hidden trouble of equipment•设备运彳亍i己录operation record of equipment•设备维护的"四项要求"four requiremen恰for plant service设备维护标准service standard of equipment•设备维护equipment service•设备使用的“三好"three well doing for use of facility•设备使用过程process of machine operation•设备三级保养three-level service system for equipment•设备日常点检routine inspection•设备清洗（清扫）cleaning of plant•设备漏油标准oil leakage standard•设备利用系数utilization factor of equipment•人身保护装置personal safety device•强制保养mandatory service•潜在故障latent filure•偶发故障期accidental failure period•磨损性故障wearout failure•例行保养（例保）routine service•密封点sealed point•劣化趋向管理degradation trend control•随机故障random failure•设备的定期维护periodic service of equipment•负荷试运行commissoning under load•故障类型failure type•故障率（失效率）failure rate•故障率基本类型basic forms of failure rate•故障模式failure mode•故障模型failure model•故障弱化failure weakening•故障树分析FTA,fault tree analysis•故障物理学physics of failure•故障停机率breakdown rate•故障征兆failure symptom•故障安全safety protection against failure•故障分析方法failure analysis method•故障机理failure mechanism•功能故障functional failure•关键设备使用维护“四定” four stipulations for operation and maintenance of critical equip•銘损（劣化）故障期exhaustion failure period•红旗设备red-flag equipment•基本故障basic failure•间断性故障intermittent failure•继发故障secondary failure•计划时间利用率utilization ratio of planned time•渐衰失效性故障local and gradual failure•渐发性（磨损）故障gradual（wear-out） failure•精、大、稀、关键设备的使用维护operation and service of precise,large scale,rare and critiT争开动时T可net operating time•可使用时间up time•可用性（可利用率）availability•可靠性为中心的维修reliability centered maintenance,ROM•平均故障间隔期（平均无故障丄作时间）mean time between failures,MTBF •破坏性故障catastrophic failure•起重机安全保护safety protection of crane•最大允许寿命（宣称寿命）maximum permitted life （declared life）•自显故障self-displayed failure•综合试运行total commissioning•专群结合combi nation of specialists and masses•调整adjustment•跟踪检备trail checkout•法定检查lawful inspection•动特性试验dynamic performanee test•动态精度dynamic accuracy动态检验dynamic test•定期J点检periodic fixed point inspection•定期检查periodic inspection•定期参数检查periodic parameter examination•定期润滑检查periodic lubrication check•“三位一体”点检制"three in one" fixed point inspetion system•主观（五官）判断故障subjective（sensible） failure deciding•—般目视检查general visual inspection•影响设备效率的六大损失six major losses affecting running efficiency•正常检查normal inspection•巡回检查patrol inspection•巡回检测patrol test•无损检查non-destructive test•停机时间down time•微观组织检查exami nation of microscopic structure•损坏break down•缺陷defect•失效（故障）failure•容许故障率allowable failure rate•日常检查daily inspection•日常润滑检查daily lubrication check•设备点检fixed point inspect!on of equipment•设备检查facilities inspection•设备监测equipment monitoring•设备故障频率equipment failure frequency•设备故障管理效果评价result evaluation of plant failure management •设备诊断技术equipment diagnostic technique•设备诊断equipment diagnosis•酸洗检查inspection with pickling•敲打检查hammering test磨损检查wearing inspection•内表面检查inner surface inspection•故障强度率failure intensity rate•故障趋于零的“四个阶段” "four steps*' to zero failure•故障危害程度harm extent of failure•故障为零的五项措施five measures to zero failure•故障（停机）损失breakdown loss•故障管理程序program of railure management•故障管理信息information of failure management•故障修理troubleshooting•功能检查（功能测试）function inspection,function test•宏观组织检查examination of macroscopic structure•检定周期cycle of verification•技术维护technical service•季节性技术维护seasonal technical service•计划保全管理planned maintenance management•解体检查inspection under disassembled condition•精度检查accuracy inspection•静态精度static accurary•可靠性试验reliability test•可靠性分析reliability analysis•平均寿命时间（MTTF） mean time to failure•状态监测condition monitoring•状态检查condition inspection•点检的主要环节main items of fixed point inspection改善修理corrective maintenance•返修率back repair rate•分级修理stepped（sizing） repair•分散修理制decentralized maintenance system•废次品及返修损失waste and ungraded product and back repair loss •非预定维修时间unscheduled maintenance time•定期修理作业periodic repair task•定期维修法periodic repair•定位精度location accuracy•传动精度transmission accuracy•大修计划修改revision of overhaul plan•大修计划考核assesment of overhaul plan•大修计划编制overhaul planning•大修i I•划依据basis of overhaul plan•大修计划完成率fulfilment rate of overhaul plan•大修计划实施implementation of overhaul plan•大修费用overhaul cost•大修成本构成overhaul cost•大修成本分析overhaul cost analysis•大修成本完成率fulfilment rate of overhaul cost•大修保修overhaul guarantee•大修周期interval between overhauls, overhaul cycle•大修质量保证体系guarantee system of overhaul quality•大修理质量评定overhaul quality evaluation•大修理质量控制overhaul quality control•大修overhaul,capital repair•部件修理法assembly repair•部分修理法partial repair•补偿法compensation method•备件生产计戈i] product!on program of spqre parts备份或冗余系统stand-by or redundancy system•标准尺寸修理法standard-size repair method•八步法"eight steps M method•重复定位幡度repeat location accuracy•中修middle repair•有可维修备份的系统system with maintainable standby parts •远距离维修remote maintenance•预防维修preventive maintenance•预定维修时间scheduled maintenance time•预知维修（状态监测维修）predictive maintenance•质量体系quality system•质量quality•逾期维修deferred maintenance•网络计划network planning•维修技术培训maintenance skill training•维修间隔（正常运行时间）maintenance interval, uptime•维修活动的经济分析economic analysis of maintenanee activities •维修工人maintenance worker•维修防护maintenance protection•维修车间maintenance shop•维修预防maintenance prevention•维修周期maintenance cycle•维修时间maintenance time•同步修理法synchronous repair•停修时间repair downtime•项修（项目修理）item repair•夕卜委修理repair on commission•全员参加的生产维修制（TPM） total production maintenance system •受控维修controlled maintenance•寿命周期维修life cycle maintenance热修hot repair•设备修理计划repair schedule of equipment•设备修理验收acceptance check for equipment repair•设备季度修理i|•划quarterly repair schedule of equipment•设备技术考核technical check of equipment•设备大修计划equipment overhaul plan•设备月度修理计划monthly repair schedule of equipment•设备维修计划equipment maintenance plan•设备维修三要素three essential factors of equipment maintenance •设备项修计戈ij item repair plan of equipment•设备年度修理讣划annual repair schedule of equipment•事后修理breakdown maintenance•抢修first-aid repair•大修机床精度accuracy of machine tool after overhaul•滚动计划rolling （circulation） plan•管理信息系统维修MIS maintenance•工程能力指数process capacity index•工作精度working accuracy•恢复性修理recovery repair•机床旋转精度rotational accuracy of machine tool•机修车间（分厂）machine repair shop•机修技工maintenance mechanic•机械修复法mechanical repair method•机械的瞬时效率instantaneous efficiency of machinery•互换法interchange method•检验inspection•集中修理制centralized maintenance system•儿何精度geometric accuracy•季节性修理seasonal repair•计划外修理repair out of plan讣划维修scheduled maintenance•计划预修制（nriP） planned preventive maintenance system•计划修理planned repair•接触精度contact accuracy•紧急修理作业emergency repair task•就地加工修配法machining and fitting method on the spot•精度指数precision index•精度标准accuracy standard•精度保持性precision retaining ability•精度储备precision reserve•精修fine repair•精修技工fine repair mechanic•经济精度economic accuracy•平衡精度等级balancing precision grade•平均修理时间mean time to repair(MTTR), mean repair time•小修minor repair•修配法fitting method•修配环repair link•修理任务书repair specification•修理施工调度repair rasks dispatch•修理时间repair time, shutdown time•修理停歇时间定额downtime quota for equipment repair•修理用设备repair facilities•修理质量repair quality•修理质量指标repair quality index•修理质量计划repair quality plan•修理质量考核repair quality assessment•修理标识repair symbols•修理成本考核repair cost assessment•修理尺寸repair size修理定额repair quota•修理费用定额repair cost quota•修理方案repair scheme•修理工时定额repair manhour quota•修理工时考核repair man hours assessme nt•修理工艺repair technology•修理丄程车maintenance engineer!ng truck•修理工具maintenance tool•修理工期考核repair time limit assessment•修理考核repair assessment•0药前预检inspection before repair•修前测绘measuring and drawing before repair•修前访问inquiry before repair•彳彥后月艮务service after repair•最优修理周期optimum repair cycle•装配精度assembly accuracy•电修车间(分厂)electric repair shop•电修技工maintenance electrician•单台设备修理费用核算repair cost accounting for single equipment •调整法adjustment method•调整环adjusting link覆盖件covering parts•返修品back repaired products•分散（混合）储备decentralized storage•分散生产方式decentralized production mode•分散生产分散储备decentralized production and decentralized storage •废品损失rejection loss•废品率rejection rate•废品waste products•存放合理化storage rationalization•储备形式storage form•储备恢复周期（订货间隔期）interval betwee no rders•储备限额storage limit•大型铸锻件large-sized casting and forging•次品substandard products•超差品over-tolerance products•常备备件runing spare parts•成品finished products•成品储备storage of finished products•成对储备conjugated storage•成对（套）件conjugated parts•部件储备storage of assembles•部件assembly•仓库面积利用率utilization ratio of storehouse area•备件的"五清” "five clear M for spare parts•备件自给率self - sufficiency rate of spare parts•备件自然失效natural failure of spare parts•备件资金的核算法accounting method of spare parts fund•备件资金占用率occupation rate of spare parts fund•备件资金周转期turnover period of spare parts fund•备件资金周转率turnover rate of spare parts fund备件考核指标assessment criteria of spare parts managment•备件卡基础资料elementary data of spare parts cards•备件卡（帐）cards of spare parts•备件库的“五五码放” “five - five tiering"for storehouse of spare parts •备件库的“三一致” "three coincidence”for storehouse of spare parts •备件库的"三清” "three clear M for storehouse of spare parts •备件库的"两齐” "two neatness'for storehouse of spare parts•备件库管理工作management of spare parts storehouse•备件库存供应率supply rate of spare parts inventory•备件库保管员职责responsibility of spare parts storehouse manager•备件库职责responsibilities for storehouses of spare parts•备件库storehouse for spare parts•备件经济管理economic management of spare parts•备件经常储备定额regular storage quota of spare parts•备件计划员planner responsible for spare parts•备件i I•算机管理computer - aided management of spare parts•备件技术员technician responsible for spare parts•备件技术失效technical failure of spare parts•备件汇总collection of spare parts•备件合用率suitability of spare parts•备件供应率supply rate of spare parts•备件管理计划丄作planning work of sapre parts management •备件管理技术丄作technical work of spare parts management •备件管理职责responsibility of spare parts management •备件管理spare parts management•备件范用range of spare parts•备件分类工作classifying work of spare parts•备件订货点法ordering point method of spare parts•备件订货点ordering point of spare parts•备件订货量ordering quantity of spare parts•备件定期订货法periodic ordering method of spare parts•备件定量货j去fixed ・ quantity ordering method of spare parts•备件定量保持法（维持定量法）fixed - quantity keeping method of spare parts •备件储备的“三点制” "three point system n of spare parts storage•备件储备资金限额limit of funds for reserve spare parts•备件储备资金funds for reserve spare parts•备件储备定额storage quota of spare parts•备件储备失效寿命storage life of spare parts to failure•备件成本价格cost price of spare parts•备件采购（供应）周期delivery cycle of spare parts•备件包装法packing method of spare parts•备件拥有量possessed amount of spare parts•备件周转力口速率turnover acceleration rate of spare parts•备件周转率turnover rate of spare parts•备件质量检验quality inspection of spare parts•备件图册基本内容main contents of spare parts album•备件图册质量quality of spare parts album•备件图册spare parts album•备件统计分析法statistical analysis method of spare parts•备件统计statistic of spare parts•备件i肖耗量consumption of spare parts•备件退库率return rate of spare parts•备件使用寿命service life of spare parts•备件双箱法（双储备法）double case method of spare parts•备件生产方式production mode of spare parts•备件寿命life of spare parts•备件名目卡（帐）item cards of spare parts•备件年平均库存金额annual average stock sum of spare parts•备件ABC 管理法A,B,C management method of spare parts•备件ABC 分类法A,B,C classifying method of spare parts备件spare parts•标准件standard parts•半成品储备storage of semifinished porducts•半成品semi-finished products•易损件vulnerable parts•中心备件库central storehouse of spare parts•一般备件running spare parts•液压件hydraulic parts•在制品articles being processed•循环性备件repairable spare parts•限寿机件life-limited item•特殊储备special storage•橡胶件rubber parts•替代品substitute products•维修用外购物资outsourcing materials used for maintenance•通用酉i!件商品化commercialization of general-purpose spare parts•微电子器件micro-electronic parts of appliances肖耗性备件consumptive spare parts•消耗定额consume quota•夕卜协件outsourcing manufactured parts•外购备件储备定额公式storage quota formula of outsourcing spare parts•夕卜Ji沟备件outsourcing spare parts•确定备件的结构分析法structural analysis method for determining spare parts 闰滑件lubricating parts•设备备件综合卡（帐）integrated cards of equipment spare parts•设备备件卡（帐）cards of equipment spare parts•强制更换件mandatory replacement item•每个复杂系数备件资金fund of spare parts per complexity coefficient•毛坯库storehouse for stocks•毛坯件stock毛坯储备storage of stock•密封件sealing parts•配件fittings•通用（共用）件general-purpose parts•光学系统备件parts of optical system•贵重备件valuable spare parts•管路备件spare parts for pipes•工程塑料件engineering plastic parts•关键备件critical spare parts•机械零件machine parts•机械备件mechanical spare parts•间断储备discontinued storage•集中生产（订货）分散储备decentralized storage•集中生产方式centralized production mode•集中储备centralized storage•紧固件fastenings•进口设备酉t!件spare parts for imported equipment•精密（高精）备件precision （high precision） spare parts•经常储备regular storage•可互换件（双向互换件）interchangeable （two-way interchangeable） item •气动元件pneumatic elements•七类关键件seven kinds of critical parts•修复件restored parts•组合件combined parts•最经济力口工循环期the most economical period for process!ng spare parts •自制备件homemade spare parts•自制备件生产计划production program of spre parts•自制备件制造周期manufacturing period of homemade spare parts•电器元件electrical elements•电器（气）备件eletrical spare parts电子产品备件spare parts of electronic products•彳氐丿E 电器low-voltage electric appliances•单向互换件one-way interchangeable item。