Api580 chapter 7 to 9

Charlie Chong/ Fion ZhangAPI 580

7 Planning the RBI Assessment评估计划


Contents

7 Planning the RBI Assessment 7.1 Getting Started 7.2 Establishing Objectives and Goals of an RBI Assessment 7.3 Initial Screening 7.4 Establish Operating Boundaries 7.5 Selecting a Type of RBI Assessment 7.6 Estimating Resources and Time Required


7.1 Getting Started 开始This section helps a user determine the scope and the priorities for an RBI assessment. Screening is done to focus the effort. Boundary limits are identified to determine what is vital to include in the assessment. The organizing process of aligning priorities, screening risks, and identifying boundaries improves the efficiency and effectiveness of conducting the RBI assessment and its end-results in managing risk. An RBI assessment is a team-based process. At the beginning of the exercise, it is important to answer the following questions.分析作业前需要确定的几点


What codes and standards are applicable?

How the RBI assessment will be carried out?

What data is to be used in the assessment?

Why the assessment is being done?

Which facilities, assets, and components will be included?

What is the plan period?Who is responsible and accountable for what actions?

How the results will be used?What are their roles in the RBI process?

How long the assessment will remain in effect and when it will be updated?

Who is on the RBI team?

When the assessment will be completed?

What knowledge and skills are required for the assessment?


At the conclusion of the planning portion of the development of the RBI program, the following should have been completed: 以下为整个计划必须完成的前期规划点

a) establish the objectives of the risk analysis, 建立风险分析的目标b) identify the physical boundaries, 识别物理边界c) identify the operating boundaries, 确定操作范围d) develop screening questions and criteria consistent with the objectives of the

analysis and identified physical and operating boundaries.根据上述三点, 开发筛选问题和一致准据


识别物理边界


确定操作范围


Once this portion of the RBI planning process has been completed, the data and information required for collection should be identified (see Section 8). Note that it may be necessary to revise the objectives, boundaries, screening questions, etc., based upon the availability and quality of the data and information.

当上述的事项认明后, 需要收集的数据和资料应相应的确定与开始收集.需要注意的是, 上述的变数可能按照需要做修改.


7.2 Establishing Objectives and Goals of an RBI Assessment 确立目标和目的

7.2.1 General 明确7.2.2 Understand Risks 认识风险7.2.3 Define Risk Criteria 风险准据定义7.2.4 Management of Risks 风险管理7.2.5 Reduce Costs 降低成本7.2.6 Meet Safety and Environmental Management Requirements 环保要求7.2.7 Identify Mitigation Alternatives 确定缓解的替代7.2.8 New Project Risk Assessment 新的项目风险评估7.2.9 Facilities End of Life Strategies 临近终使用期策略


7.2 Establishing Objectives and Goals of an RBI Assessment 确立目标和目的

7.2.1 General 明确An RBI assessment should be undertaken with clear objectives and goals that are fully understood by all members of the RBI team and by management. Some examples are listed in 7.2.2 to 7.2.9.

7.2.2 Understand Risks 认识风险An objective of the RBI assessment may be to better understand the risks involved in the operation of a plant or process unit and to understand the effects that inspection, maintenance and mitigation actions have on the risks.From the understanding of risks, an inspection program may be designed that optimizes the use of inspection and plant maintenance resources.从认识风险,设计一份检验计划来完善检验工作和利用实际的工厂维护资源.


7.2.3 Define Risk Criteria 定义风险准据An RBI assessment will determine the risk associated with the items assessed. The RBI team and management may wish to judge whether the individual equipment item and cumulative risks are acceptable. Establishing risk criteriato judge acceptability of risk could be an objective of the RBI assessment if such criteria do not exist already within the user’s company. 制定风险数据来判断风险的可接受性

7.2.4 Management of Risks 风险管理When the risks are identified, inspection actions and/or other mitigation that have a positive effect in reducing risk to an acceptable level may be undertaken. These actions may be significantly different from the inspection actions undertaken during a statutory or certification type inspection program. The results of managing and reducing risk are improved safety, avoided losses of containment, and avoided commercial losses. 当风险被识别后, (1) 检测和/或(2) 其他缓解活动, 将进行来降低风险到可接受的水平. 这些工作/活动或许显著不同法定或认证检验要求.


7.2.5 Reduce Costs 降低成本Reducing inspection costs is usually not the primary objective of an RBIassessment, but it is frequently a side effect of optimization. When theinspection program is optimized based on an understanding of risk, one ormore of the following cost reduction benefits may be realized:减少检查费用通常不是首要目标但它是经常优化的副作用

a) ineffective, unnecessary or inappropriate inspection activities may be eliminated;无效的,不必要的或不适当的视察活动可能被淘汰

b) inspection of low-risk items may be eliminated or reduced;低风险的项目进行检查也可以消除或减少

c) on-line or noninvasive inspection methods may be substituted for invasive methods that require equipment shutdown; 在职非介入检验代替介入检验, 这样能避免停机.

d) more effective infrequent inspections may be substituted for less effective frequent inspections.更有效的低频繁代替低效频繁检验


7.2.6 Meet Safety and Environmental Management Requirements 符合安全标准和环境管理要求Managing risks by using RBI assessment can be useful in implementing an effective inspection program that meets performance-based safety and environmental requirements. RBI focuses efforts on areas where the greatest risks exist. RBI provides a systematic method to guide a user in the selection of equipment items to be included and the frequency, scope, and extent of inspection activities to be conducted to meet performance objectives. 在实施有效的检查计划也带来符合基于性能的安全性及环保要求.


7.2.7 Identify Mitigation Alternatives 缓解选择识别The RBI assessment may identify risks that may be managed by actionsother than inspection. Some of these mitigation actions may include but arenot limited to:可以通过其他行动替代检查来管理风险相有;

a) modification of the process to eliminate conditions driving the risk; 工艺修改.(降低POF/COF)

b) modification of operating procedures to avoid situations driving the risk; 修改操作程序.(降低POF/COF)

c) chemical treatment of the process to reduce deterioration rates/susceptibilities;化学处理(降低POF)

d) change metallurgy of components to reduce POF;改变组件的冶金降低故障概率POF


e) removal of unnecessary insulation to reduce probability of corrosion under insulation; 去除不必要的保温层以减少腐蚀的概率(降低POF)

f) reduce or limit available inventories to reduce COF; 减少或限制设备编制(库存)降低COF

g) upgrade safety, detection or loss limiting systems;提升安全性,检测或流失限制系统(降低COF)

h) change process fluids to less flammable or toxic fluids;改变工艺流体不易燃或有毒液体(降低COF)

i) change component design to reduce POF;更改组件的设计达到降低POFj) process control and adherence to IOW.

过程控制和严守操作工艺界限.(降低POF/COF)


The data within the RBI assessment can be useful in determining the optimum economic strategy to reduce risk. The strategy may be different at different times in a plant’s life cycle. For example, it is usually more economical to modify the process or change metallurgy when a plant is being designed than when it is operating. 缓解策略在不同的周期而别(如运作/设计阶段)


The RBI assessment may identify risks that may be managed by actions other than inspection. …..

HOW INSPECTION MANAGEED RISK?

一句老话: 质量不是检出的!


7.2.8 New Project Risk Assessment 新建项目风险评估An RBI assessment made on new equipment or a new project, while in the design stage, may yield important information on potential risks. This may allow potential risks to be minimized by design and have a risk-based inspection plan in place prior to actual installation.新的项目风险评估有利于通过设计小化潜在的风险


New Project Risk Assessment












7.2.9 Facilities End of Life Strategies 设施使用寿命后期策略

Facilities approaching the end of their economic or operating service life are a special case where application of RBI can be very useful. The end of life case for plant operation is about gaining the maximum remaining economic benefitfrom an asset without undue personnel, environmental or financial risk.

End of life strategies focus the inspection efforts directly on high-risk areas where the inspections will provide a reduction of risk during the remaining life of the plant. Inspection activities that do not impact risk during the remaininglife are usually eliminated or reduced. 不影响风险的检验活动减少或删除而关注

高风险项目

End of life inspection RBI strategies may be developed in association with a Fitness-For-Service assessment of damaged components using methods described in API 579-1/ASME FFS-1. It is important to revisit the RBI assessment if the remaining plant life is extended after the remaining life strategy has been developed and implemented. 可以结合适用性评估作为更加有效的策略.


7.3 Initial Screening 初步筛选7.3.1 GeneralThe screening process focuses the analysis on the most important group of equipment items so that time and resources are more effectively utilized.焦点设备项目重要的一组

7.3.2 Establish Physical Boundaries of an RBI Assessment 物理界限Boundaries for physical assets included in the assessment are established consistent with the overall objectives. The level of data to be reviewed and the resources available to accomplish the objectives directly impact the extent of physical assets that can be assessed.来完成目标的数据水平和可用的资源影响物理界限

The scope of an RBI assessment may vary between an entire refinery or plant and a single component within a single piece of equipment. Typically, RBI is done on multiple pieces of equipment (e.g. an entire process unit) rather than on a single component. 评估范围可从全厂或小至设备的某组件. 一般来说评估范围为多个设备(例如,整个处理单元)


Typically, RBI is done on multiple pieces of equipment (e.g. an entire process unit) rather than on a single component.一般来说评估范围为多个设备 (例如,整个处理单元)


Screening Levels

1. Facilities

2. Process Units

3. Systems

4. Equipments


Facility-Plant


http://www.energyimages.com/refineryschematic.jpg

Facility-Units



process units



System – Sour Water Striper



System – CS Vessel 230psig, 230ºC , c=3mm


Equipment -Sour Water Striper Column, Condenser & CS Vessel


7.3.3 Facilities Screening 设备筛选At the facility level, RBI may be applied to all types of plants including but notlimited to:

a) oil and gas production facilities,石油和天然气生产设施b) oil and gas processing and transportation terminals,

石油和天然气加工和运输终端c) refineries,炼油厂d) petrochemical and chemical plants,石化和化工厂e) pipelines and pipeline stations,管道和管道站f) liquified natural gas plants.液化天然气工厂


石油和天然气生产设施


石油和天然气加工和运输终端


炼油厂


石化和化工厂


管道和管道站


液化天然气工厂


Examples of key questions to answer at the facility level are listed as follows.

a) Is the facility located in a regulatory jurisdiction that will accept modifications to statutory inspection intervals based on RBI? 基于风险分析方法被法定接受吗?

b) Is the management of the facility willing to invest in the resources necessary to achieve the benefits of RBI? 设施管理层愿意投资吗?

c) Does the facility have sufficient resources and expertise available to conduct the RBI assessment?是否有足够的资源和专门知识来进行评估?


facility level


facility level


设施水平需要回答的关键问题:(1) 基于风险分析方法被法定接受吗?


(2) 设施管理层愿意投资吗?


(3) 是否有足够的资源和专门知识来进行评估?


Screening at the facility level may be done by a simplified qualitative RBI assessment. Screening at the facility level could also be done by:设施水平可能通过一个简化的定性评估完成. 帅选因素有

a) asset or product value,资产或产品价值b) history of problems/failures at each facility, 在每个设施的问题/故障历史c) PSM (process safety management) /non-PSM facilities, PSM /非PSM设施d) age of facilities,设施的年龄e) proximity to the public,靠近公共设施f) proximity to environmentally sensitive areas.邻近环境敏感地区



Schematic overview of a refinery

炼油厂的总体示意图

http://www.globalspec.com/reference/79004/203279/chapter-3-fuels-from-petroleum-and-heavy-oil




Flow diagram of a typical oil refinery 典型炼油厂流程图


7.3.4 Process Units Screening 工艺装置(处理单元)筛选

If the scope of the RBI assessment is a multi-unit facility, the first step in the application of RBI is screening of entire process units to rank relative risk. The screening points out areas that are higher in priority and suggests which process units to begin with. It also provides insight about the level of assessment that may be required for operating systems and equipment items in the various units. Priorities may be assigned based on one of the following: 帅选全部处理单元, 按照优先级别(相对风险)排名. 优先级别可以根据以下被分配

a) relative risk of the process units,处理单元的相对风险b) relative economic impact of the process units, 处理单元的相对经济影响c) relative COF of the process units, 处理单元的相对的COFd) relative reliability of the process units, 处理单元相对可靠性e) turnaround schedule, 周转时间表f) experience with similar process units. 与同类处理单元经历


Examples of key questions to answer at the process unit level are similar to the questions at the facility level.

a) Does the process unit have a significant impact on the operation of the facility? 评估对设施的运作有显著影响吗?

b) Are there significant risks involved in the operation of the process unit and would the effect of risk reduction be measurable? 能显著降低风险量吗?

c) Do process unit operators see that some benefit may be gained through the application of RBI? 操作者会感受到益处吗?

d) Does the process unit have sufficient resources and expertise available to conduct the RBI assessment? 有充足的资源和专业知识执行评估吗?

e) What is the failure history in this unit? 设施故障历史记录?


Crude Oil instillation 原油蒸馏


Catalytic Reforming 催化转化


Process Units


7.3.5 Systems within Process Unit Screening 处理单元细分下系统筛选

It is often advantageous to group equipment within a process unit into systems, loops, or circuits where common environmental operating conditions exist based on process chemistry, pressure and temperature, metallurgy, equipment design and operating history. By dividing a process unit into systems, the equipment can be screened together saving time compared to treating each piece of equipment separately. In case the risks of each piece of equipment in the system show a common sensitivity to changes in process conditions, then a screening can establish one single IOW with common variables and ranges for the entire system.

Block flow or process flow diagrams for the unit may be used to identify the systems including information about metallurgy, process conditions, credible damage mechanisms and historical problems.

在工艺单元(处理单元);以相同工艺化学, 压力和温度, 冶金, 装备设计和操作历史等, 细分为工艺系统 / 环路有助于节省分析工作.

Charlie Chong/ Fion Zhang

http://en.wikipedia.org/wiki/HydrodesulfurizationHydrodesulfurization加氢脱硫过程

以设备细分为系统 – Condenser System


以相同工艺化学, 压力和温度细分为系统 300psig


以冶金细分为系统 – Carbon Steel


Delayed Coker 延迟焦化装置 – Coke Drum System


Catalytic Reforming 催化转化 – Fire Heater System



When a process unit is identified for an RBI assessment and overall optimization is the goal, it is usually best to include all systems within the unit. Practical considerations such as resource availability may require that the RBI assessment is limited to one or more systems within the unit. 虽然当一个处理单元被确定为RBI评估和整体优化为评估目标, 通常好覆盖处理单元内全部系统.实际的考虑因素可能考虑到可用资源, 评估仅只能限于单元内的一个或多个系统

Selection of systems may be based on the following:择的系统可以基于以下

a) relative risk of the systems, 系统的相对风险b) relative COF of systems, 系统相对COFc) relative reliability of systems, 系统相对可靠性d) expected benefit from applying RBI to a system, 预期效果e) sensitivities of risk to changes in process conditions.

工艺条件变化的风险敏感度，


7.3.6 Equipment Item Screening 设备筛选

In most plants, a large percentage of the total unit risk will be concentrated in a relatively small percentage of the equipment items. These potential high-risk items should receive greater attention in the risk assessment. Screening of equipment items is sometimes conducted to identify the higher risk items to carry forward to more detailed risk assessment. An RBI assessment may be applied to all pressure containing equipment such as: 在很多设施, 很大的总风险比例一般上都集中在一小部分的设备. 筛选识别风险较高的设备进行更详细的风险评估. 被评估的受压设备有;

control valves (pressure boundary). 控制阀 * furnaces and boilers, 炉和锅炉

pressure-relief devices, 压力释放装置heat exchangers, 换热器

compressors (pressure boundary), 压缩机*reactors, 反应器

pumps (pressure boundary), 泵*pressure vessels, 压力容器

tanks, 罐piping, 管系

* (压力边界)


Selection of equipment types to be included is based on meeting the objectives discussed in 7.2. The following issues may be considered in screening the equipment to be included. 设备筛选考虑因素有

a) Will the integrity of safeguard equipment be compromised by damage mechanisms? 设备的完整性会被损坏机理破坏吗?

b) Which types of equipment have had the most reliability problems?哪种设备有可靠性问题?

c) Which pieces of equipment have the highest COF if there is a pressure boundary failure? 压力边界失效哪个设备会有高的COF?

d) Which pieces of equipment are subject to the most deterioration that could affect pressure boundary containment? 哪个设备退化的快导致溶液流失?

e) Which pieces of equipment have lower design safety margins and/or lower corrosion allowances that may affect pressure boundary containment considerations? 哪个设备具较低的设计安全裕度与腐蚀余量导致溶液流失(压力边界围堵)?


A horizontal, recirculatingthermosyphon reboiler循环热虹吸重沸器

Boiler feedwater deaerator锅炉给水除氧器

http://en.wikipedia.org/wiki/User:Mbeychok/MRB%27s_image_gallery


7.3.7 Utilities, Emergency and Off-plot Systems 后勤,应急与外场系统

Whether or not utilities, emergency and off-plot systems should be included depends on the planned use of the RBI assessment and the currentinspection requirements of the facility. Possible reasons for inclusion of off-plot and utilities are listed below as follows.

a) The RBI assessment is being done for an overall optimization of inspection resources and environmental and business COF are included.整体优化(检验/环境/企业影响)

b) There is a specific reliability problem in a utility system. An example would be a cooling water system with corrosion and fouling problems. An RBI approach could assist in developing the most effective combination of inspection, mitigation, monitoring, and treatment for the entire facility.在后勤系统中特定的可靠性问题,RBI作为可信解决方案


c) Reliability of the process unit is a major objective of the RBI analysis.工艺设备的可靠性是RBI分析的一个主要目标

When emergency systems (e.g. flare systems, emergency shutdown systems)are included in the RBI assessment, their service conditions during both routine operations and upset should be considered.急系统评估,应当考虑,设备日常与倾覆运转



7.4 Establish Operating Boundaries 制定操作范围7.4.1 General 总则Similar to physical boundaries, operating boundaries for the RBI study are established consistent with the study objectives, level of data to be reviewed and resources. The purpose of establishing operational boundaries is to identify key process parameters that may impact deterioration. The RBI assessment normally includes review of both POF and COF for normal operating conditions. Start-up and shutdown conditions as well as emergency and non-routine conditions should also be reviewed for their potential effect on POF and COF.

制定操作范围的目的是识别可能会影响恶化的关键工艺参数. 在启动/关机以及紧急和非常规条件下操作对 POF/COF 潜在影响也是审查项.


The operating conditions, including any sensitivity analysis, used for the RBI assessment should be recorded as the operating limits for the assessment.Operating within the boundaries is fundamental to the validity of the RBI studyas well as good operating practice. It is vital to establish and monitor key process parameters that may affect equipment integrity to determine whether operations are maintained within boundaries (i.e. IOWs).

操作条件, 包括任何的敏感性分析作为 RBI分析参数, 应记录为操作限制. 在这限制下操作也是风险评估的有效性基础, 以及有效性良好的运行实践








7.4.2 Start-up and Shutdown 启动和关机Process conditions during start-up and shutdown can have a significant effect on the risk of a plant especially when they are more severe (likely to cause accelerated deterioration) than normal conditions, and as such should be considered for all equipment covered by the RBI assessment. A good example is polythionic acid stress corrosion cracking (PTASCC). The POF for susceptible equipment is controlled by whether mitigation measures are applied during shutdown procedures to avoid PTASCC. Start-up lines are often included within the process piping and their service conditions during start-up and subsequent operation should be considered.

启动和关机过程中的工艺条件, 可能对设备加速劣化从而对风险有显著负面影响. 这也是RBI评估应考虑的范围.


7.4.3 Normal, Upset, and Cyclic Operation 正常,颠覆,循环操作

The normal operating conditions may be most easily provided if there is a process flow model or mass balance available for the plant or process unit. However, the normal operating conditions found on documentation should be verified by unit operations personnel as it is not uncommon to find discrepancies between design and operating conditions that could impact the RBI results substantially.

流程模型和物量配平衡的数据一般能很方便的作为平常操作参数的来源,然而这文档数据与现实数据可能存在偏差.这些文档数据应当由生产操作人员核实以导致RBI错误的评估.


the normal operating conditions found on documentation should be verified by unit operations personnel as it is not uncommon to find discrepancies between design and operating conditions that could impact the RBI results substantially.


The following data should be provided: 下列为必须提供的数据

a) operating temperature and pressure including variation ranges,操作温度和压力以及的变化范围

b) process fluid composition including variation with feed composition ranges,过程流体成分变化,包括原料成分波动范围

c) flow rates including variation ranges, 流速包括波动d) presence of moisture or other contaminant species. 含水量与其他污染物

Changes in the process, such as pressure, temperature or fluid composition,resulting from unit abnormal or upset conditions should be considered in theRBI assessment.非正常或颠覆情况导致的工艺参数变化(比如:压力,温度,流体成分,等)也应当作

为评估考虑范围


The RBI assessment on systems with cyclic operation, such as reactor regeneration systems, should consider the complete cyclic range of conditions. Cyclic or intermittent conditions could impact the POF due to some damage mechanisms (e.g. mechanical fatigue, thermal fatigue, corrosion-fatigue, and corrosion under insulation). Examples include pressure swing absorption vessels, catalytic reforming unit regeneration piping systems, deaerator vessels, and insulated equipment that normally operates at higher temperatures but is subjected to periods of inactivity. 再生系统循环操作带来的操作参数范变动也是考虑项.




7.4.4 Operating Time Period 操作时间段

The unit run lengths of the selected process units/equipment is an important limit to consider. The RBI assessment may include the entire operational life, or may be for a selected period. For example, process units are occasionally shut down for maintenance activities and the associated run length may depend on the condition of the equipment in the unit. An RBI analysis may focus on the current run period or may include the current and next-projected run period. The time period may also influence the types of decisions and inspection plans that result from the study, such as inspection, repair, replace, operating, and so on. Projected operational changes are also important as part of the basis for the operational time period.

对于间断性工作与中间维修的设备, 评估可包括在整个运行寿命,或者可以为选定的间隔(当前运作至周转的时间间隔,或更长的间隔时段).


7.5 Selecting a Type of RBI Assessment 选择RBI评估的类型Selection of the type of RBI assessment will be dependent on a variety of

factors, such as:依赖于多种因素

a) is the assessment at a facility, process unit, system, equipment item, or component level;评估的级别; 设施, 处理单元, 系统, 设备项目或组件

b) objective of the assessment;评估的目的c) availability and quality of data;可用性和数据的质量d) resource availability;资源可用性e) perceived or previously evaluated risks;意识或之前的风险评估f) time constraints.时间限制


A strategy should be developed, matching the type of assessment to the expected or evaluated risk. For example, processing units that are expected to have lower risk may only require simple, fairly conservative methods to adequately accomplish the RBI objectives. Whereas, process units which have a higher expected risk may require more detailed methods. Another example would be to evaluate all equipment items in a process unit qualitatively and then evaluate the higher risk items identified more quantitatively. See 6.3 for more on types of RBI assessment.

评估策略应符合分析目的与预期风险; 例如, 风险较低的处理单元可能只需要简单的，相当保守的方法.然而, 有较高预期风险的处理单元需要更详细的方法.

另一个例子是将所有单元设备项目首先做定性评估, 然后确定的高风险项目再对

高风险项目更加的详细的定量评估


评估策略应符合分析目的与预期风险; 例如, 风险较低的处理单元可能只需要简单的，相当保守的方法.然而, 有较高预期风险的处理单元需要更详细的方法.

另一个例子是将所有单元设备项目首先做定性评估, 然后确定的高风险项目再对高风险项目更加的详细的定量评估


7.6 Estimating Resources and Time Required 估算资源及所需时间

The resources and time required to implement an RBI assessment will vary widely between organizations depending on a number of factors including:不同组织之间有很大的差别. 依赖许多因素如

a) implementation strategy/plans,实施策略/计划b) knowledge and training of implementers, 实施者的培训/知识c) availability and quality of necessary data and information,

必要数据/信息的可获取性与质量d) availability and cost of resources needed for implementation,

实施资源可获取性e) amount of equipment included in each level of RBI analysis,设备的数量f) degree of complexity of RBI analysis selected,所选分析的复杂度g) degree of precision required. 精确度要求


The estimate of scope and cost involved in completing an RBI assessment might include the following: 用于完成评估的范围和费用的估算

a) number of facilities, units, equipment items, and components to be evaluated;被评估的设备, 单元, 设备及元件数量,

b) time and resources required to gather data for the items to be evaluated; 收集数据所需要的时间与资源,

c) training time for implementers; 人员培训时间,d) time and resources required for RBI assessment of data and information;

分析资料的时间与资源,e) time and resources to evaluate RBI assessment results and develop

inspection, maintenance, and mitigation plan.评估分析结果,制定检查, 维护和缓解计划的时间与资源.


8 Data and Information Collection for RBI Assessment 数据和信息收集



Contents

8 Data and Information Collection for RBI Assessment 8.1 General 8.2 RBI Data Needs 8.3 Data Quality 8.4 Codes and Standards—National and International 8.5 Sources of Site Specific Data and Information


8.1 General 总则

Utilizing the objectives, boundaries, level of approach and resources identified in Section 7, the objective of this section is to provide an overview of the data that may be necessary to develop an RBI plan. The data collected will provide the information needed to assess potential damage mechanisms, potential failure modes and scenarios of failure that are discussed in Section 9. Additionally, it will provide much of the data used in Section 10 to assess probabilities, the data used in Section 11 to assess consequences and data used in Section 13 to assist in inspection planning.


收集的数据作为评估潜在的损害机制, 故障概率与失效后果所需要的信息按照第七章描述的,设定的目标,范围,处理深度,可用资源收取所应当需要的数据.数据用来作为;

第九章: 分析,损坏机理,失效模式/情景第十章: 分析失效概率第十一章: 分析失效后果第十三章: 策划检验计划


Examples of data sources include: 数据源的例子包括

a) design and construction records; 设计和施工记录b) inspection and maintenance records; 检查和维修记录c) operating and process technology records; 操作和工艺技术记录d) hazards analysis and MOC records; 危害分析和建设部记录e) materials selection records; corrosion engineering records & library/database;

材料选择记录f) cost and project engineering records. 成本和项目工程记录

The precision of the data should be consistent with the RBI method used. The individual or team should understand the precision of the data needed for the analysis before gathering it.

数据的精度应和所用的RBI方法要求一致.



It may be advantageous to combine risk analysis data gathering with otherisk/hazard analysis data gathering (see 6.7) as much of the data may be thesame. (PHA, RCM, QRA)

数据收集时, 可以考虑结合其他风险/危害分析的数据收集



8.2 RBI Data NeedsAn RBI study may use a qualitative, semi-quantitative and/or quantitative approach (see 6.3). A fundamental difference among these approaches is the amount and detail of input, calculations and output. 不同的评估方法需要不同的数据, 这些方法之间的根本区别是; 输入,计算和输出的(1)数量和(2)细节 .

For each RBI approach it is important to document all bases for the study and assumptions from the onset and to apply a consistent rationale. Any deviations from prescribed, standard procedures should be documented.

基点, 假设作为评估的宗旨, 从开始,到运用应当保持一致.任何从新规定,标准/程序的偏差应做记录.


Documentation of unique equipment and piping identifiers is a good starting point for any level of study. The equipment should also correspond to a unique group or location such as a particular process unit at a particular plant site. 每个被评估设备应当有自个唯一的识别号.



不同的评估方法需要不同的数据, 这些方法之间的根本区别是; 输入, 计算和输出的: (1) 数量和 (2) 细节.

基点-假设作为评估的宗旨,从开始,到运用应当保持一致.任何从新规定,标准程序的偏差应做记录.


9. damage mechanisms, rates, and severity; 损伤机制,速度和严重性

10.personnel densities; 人员密度

11.coating, cladding, and insulation data; 涂层,覆层和保温数据

12.business interruption cost; 业务中断成本

13.equipment replacement costs;设备更换成本

14.environmental remediation costs.环境整治费用

1. type of equipment; 设备的类型

2. materials of construction; 结构材料

3. inspection, repair and replacement records; 检查,修理和更换记录

4. process fluid compositions;过程流体成分

5. inventory of fluids; 流体盘点

6. operating conditions; 操作条件

7. safety systems; 安全系统

8. detection systems; 探测系统

Typical data needed for an RBI analysis may include but is not limited to:分析典型数据


8.2.1 Data Needs for Qualitative RBI 定性数据需求

A more qualitative approach typically does not require all of the data mentioned in 8.2. Further, items required only need to be categorized into broad ranges or classified versus a reference point. It is important to establish a set of rules to assure consistency in categorization or classification.

(较)定性的方法通常不要求上述所有提到的数据.牵涉的设备只需要分为广义范围或以参考点给以分类

Generally, a qualitative analysis using broad ranges requires a higher level of judgment, skill and understanding from the user than a more quantitative approach. Ranges and summary fields may evaluate circumstances with widely varying conditions requiring the user to carefully consider the impact of input on risk results. Therefore, despite its simplicity, it is important to have knowledgeable and skilled persons perform the qualitative RBI analysis.

通常, 使用范围广泛的定性分析, 要求更明确的判断/技能和用户对设备的了解. 因此,尽管它的简单,进行了定性分析需要更加有知识和技能的人.


通常, 使用范围广泛的定性分析, 要求更明确的判断/技能和用户对设备的了解. 因此, 尽管它的简单,进行了定性分析需要更加有知识和技能的人.


通常, 使用范围广泛的定性分析, 要求更明确的判断/技能和用户对设备的了解. 因此, 尽管它的简单,进行了定性分析需要更加有知识和技能的人.


8.2.2 Data Needs for Quantitative RBI 定量分析数据要求

QRA uses logic models depicting combinations of events that could result in severe accidents and physical models depicting the progression of accidents and the transport of a hazardous material to the environment. The models are evaluated probabilistically to provide both qualitative and quantitative insights about the level of risk and to identify the design, site, or operational characteristics that are the most important to risk. Hence, more detailed information and data are needed for a fully quantitative RBI in order to provide input for the models.

定量风险分析, 使用逻辑模型来描述可能导致严重事故发生的组合. 该模型是以概率性评估来提供定性和定量的共同洞察问题. 识别设计, 场地或操作特性对风险的影响. 因此, 需要更详细的信息和数据


8.2.3 Data Needs for Semi-quantitative RBI 进行半定量评估数据需求The semi-quantitative analysis typically requires the same type of data as a quantitative analysis but generally not as detailed. For example, the fluid volumes may be estimated. Although the precision of the analysis may be less, the time required for data gathering and analysis will be less too; however that does not mean that the analysis will be less accurate (see 6.4).

半定量分析通常需要作为定量分析相同类型的数据, 但一般不用那么的详细.虽然分析的精度可能较少, 相应所需的数据收集和分析的时间将减少, 但是, 这并不意味着该分析将是不准确的.


8.3 Data Quality 数据质量

The data quality has a direct relation to the relative accuracy of the RBI analysis. Although the data requirements are quite different for the varioustypes of RBI analysis, quality of input data is equally important no matter whatapproach to RBI is selected. It is beneficial to the accuracy and quality of an RBI analysis to assure that the data input are up to date and validated by knowledgeable persons (see Section 16).

确保证数据输入的是新的和有知识的人进行数据验证.

As is true in any inspection program, data validation is essential for a number of reasons. Among the reasons for inspection data quality errors are:检查数据质量误差,其中的原因有

a) outdated drawings and documentation,过时的图纸和文档b) inspection error, 检查误差c) clerical and data transcription errors, 文书及数据抄写错误d) measurement equipment accuracy. 测量设备的精度


Another potential source of scatter and error in the analysis is assumptions on equipment history. For example if baseline inspections were not performed or documented, nominal thickness may be used for the original thickness. This assumption can significantly impact the calculated corrosion rate early in the equipment life.

The effect may be to mask a high corrosion rate or to inflate a low corrosion rate. A similar situation exists when the remaining life of a piece of equipment with a low corrosion rate requires inspection more frequently.

The measurement error may result in the calculated corrosion rate appearing artificially high or low. It is important that those making assumptions understand the potential impact of their assumptions on the risk calculation.

数据偏差和误差分析, 的另一个潜在来源是对设备历史错误的假设如没有进行设备基线调查导致错误的腐蚀率计算.




This validation step stresses the need for a knowledgeable individualcomparing data from the inspections to the expected damage mechanism and rates. This person may also compare the results with previous measurements on that system, similar systems at the site or within the company or published data. Statistics may be useful in this review.

This review should also factor in any changes or upsets in the process. As mentioned previously, this data validation step is necessary for the quality of any inspection program, not just RBI.

Unfortunately, when this data validation step has not been a priority before RBI, the time required to do it gets included with the time and resources necessary to do a good job on RBI, leaving the wrong impression with some managers believing that RBI is more time consuming and expensive than it should be.数据验证, 是确保任何检查程序质量的必要步骤, 而不是仅限于风险分析检验. 往往这数据验证牵涉到的时间与费用, 错误的只在 RBI 体现, 导致有的管理者感觉RBI 更耗时且昂贵的管理方法.


8.4 Codes and Standards—National and International规范与标准- 国家和国际

In the data collection stage, an assessment of what codes and standards are currently in use for in-service inspection and evaluation, or were in use during the equipment design, is generally necessary. The selection and type of codesand standards used by a facility can have a significant impact on RBI results.

确定使用标准与规范的是重要的. 选用的标准与规范对评估的结果有显著地影响.

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8.5 Sources of Site-specific Data and Information 场地特定的数据和信息来源

Information for RBI can be found in many places within a facility. It is important to stress that the precision of the data should match the complexity of the RBI method used (see 6.4). The risk analysis and RBI team should understand the sensitivity of the data needed for the program before gathering any data. It may be advantageous to combine RBI data gathering with other risk/hazard analysis data gathering (e.g. PHA, RCM, QRA) as much of the data overlaps.

数据的精度应和所用的RBI方法一致. 在做数据收集时, 可以考虑结合其他风险/危害分析的数据收集. 如: PHA, RCM, QRA


Potential sources of specific information include but are not limited to: 具体信息的潜在来源包括;

a) design and construction records/drawings: 设计和施工记录/图

P&IDs, process flow diagrams, material selection diagrams (MSDs), etc., 仪表工艺图/工艺流程图/材料选择图

piping isometric drawings, 管线三维图 engineering specification sheets,工程规格表 materials of construction records,施工材料记录 construction QA/QC records, 建设QAQC记录 codes and standards used,规范和使用标准 protective instrument systems,防护仪器系统


Potential sources of specific information include but are not limited to: 具体信息的潜在来源包括;

a) design and construction records/drawings: 设计和施工记录/图

P&ID, process flow diagrams, material selection diagrams (MSDs), etc., 仪表工艺图/工艺流程图/材料选择图

piping isometric drawings, 管线三维图 engineering specification sheets, 工程规格表 materials of construction records, 施工材料记录 construction QA/QC records, 建设QAQC记录 codes and standards used, 规范和使用标准 protective instrument systems, 防护仪器系统


leak detection and monitoring systems, 泄漏检测和监控系统 isolation systems, 隔离系统 inventory records, 库存记录 emergency depressurizing and relief systems, 紧急减压系统及减压系统 safety systems, 安全系统 fire-proofing and fire-fighting systems, 防火和灭火系统 layout; 布置图



b) inspection records:检查记录

schedules and frequency, 时间表和频率 amount and types of inspection, 检查次数和类型 repairs and alterations, 修复与更改 positive material identification (PMI) records, 材料鉴定记录 inspection results; 检查结果

c) process data, 工艺过程数据

fluid composition analysis including contaminants or trace components,流体成分分析包括污染物或痕量组分

distributed control system data, 分布式控制系统数据 operating procedures, 操作程序 start-up and shutdown procedures, 启动和关闭程序 emergency procedures, 应急程序 operating logs and process records, 操作日志和过程记录 PSM, PHA, RCM, and QRA data or reports; 其他安全/风险分析法数据记录


d) MOC records; 设备变动管理记录

e) off-site data and information - if consequence may affect off-site areas; 影响设施的外场信息与数据

f) failure data: 故障数据

generic failure frequency data-industry or in-house,一般的故障频率(数据行业或内部)

industry specific failure data, 行业特定的故障数据 plant and equipment specific failure data, 设施与设备的具体故障数据 reliability and condition monitoring records, 可靠性和状态监测记录 leak data; 泄露数据

g) site conditions: 现场条件

climate/weather records, 气候/天气记录 seismic activity records; 地震活动记录


seismic activity records


seismic activity records


h) equipment replacement costs: 设备更换费用

project cost reports, 工程造价的报告 industry databases; 行业数据库

i) hazards data: 危害数据

PSM studies, PHA studies, QRA studies, other site specific risk or hazard studies; 其他风险或危害的研究

j) incident investigations. 事故调查


9 Damage Mechanisms and Failure Modes 损伤机理和失效模式


Contents

9 Damage Mechanisms and Failure Modes 9.1 Introduction 9.2 Damage Mechanisms 9.3 Failure Modes 9.4 Accumulated Damage 9.5 Tabulating Results



9.1 Introduction 概述

This section provides guidance in identifying credible damage mechanisms and failure modes of pressure boundary metallic components that should be included in an RBI analysis. Guidance is also provided in other documents.Damage mechanisms in the hydrocarbon process industry are addressed in API 571. ASME PCC-3 also has some useful information and appendices on damage mechanisms. See 16.2.4 for the type of person with knowledge in materials and corrosion that should be involved in the process.

本节提供指导确定可信的损伤机理和失效模式.其他行业文章也提供这方面的指导,参考文件有;API571ASME PCC-3 Inspection Planning Using Risk-Based Methods



Damage mechanisms include corrosion, cracking, mechanical and metallurgicaldamage. Understanding damage mechanisms is important for:了解损伤的机制是重要的因为有助于以下活动;

a) the analysis of the POF; 失效概率的分析b) the selection of appropriate inspection intervals/due dates, locations and

techniques; 适当的安排检查间隔/到期日期, 位置和选择对应的检验技术c) the ability to make decisions (e.g. modifications to process, materials

selection, monitoring, etc.) that can eliminate or reduce the probability of a specific damage mechanism. 提供足够的信息做可消除或减少特定损伤机制的可能性的决策.



Failure modes identify how the damaged component will fail (e.g. by leakage or by rupture). 失效模式确定损坏的组件将如何失败 (例如, 由泄漏或破裂) Understanding failure modes is important for three reasons: 了解故障模式有三个重要原因(有助于)a) the analysis of the COF, 失效后果的分析b) the ability to make run-or-repair decisions, “运行-或-修复”决策的能力c) the selection of repair techniques. 维修方法的选择



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9.1.1 Identification of Damage Mechanisms 损伤机理的鉴定

Identification of the credible damage mechanisms and failure modes for equipment included in a risk analysis is essential to the quality and the effectiveness of the risk analysis. The RBI team should consult with a corrosion specialist to define the equipment damage mechanisms, damage modes (optional), and potential failure modes. A sequential approach is as follows.

应咨询腐蚀专家以确定设备损坏机理, 破坏模式(可选), 和潜在的失效模式.做法顺序如下


a) As indicated in Section 7, identify the internal and external operating and environmental conditions, age, design and operational loading. Data used and assumptions made should be validated and documented. Processconditions as well as anticipated process changes should be considered. Identifying trace constituents (ppm) in addition to the primary constituents in a process can be very important as trace constituents can have a significant affect on the damage mechanisms.

识别内部和外部的操作和环境条件,龄期, 设计和运行负荷. 应考虑工艺条件以及预期的变化, 除了主要成分应识别微量成分. 这微量成分可能对损伤机制显著影响.


b) Considering the materials, methods and details of fabrication, develop a list of the credible damage mechanisms that may have been present in past operation, be presently active, or may become active. 开发(1)可能已经存在(2) 在过去的操作中曾经发生或 (3)可能变得活跃, 可信的损害机制的列表

c) Under certain circumstances it may be preferable to list a specific damage mechanism and then list the various damage modes or ways that the damage mechanism may manifest itself. For example, the damage mechanism “corrosion under insulation” may precipitate a damage mode of either generalized corrosion or localized corrosion. Generalized corrosion could result in a large burst while localized corrosion might be more likely to result in a pinhole type leak. All credible failure modes for each damage mechanism or damage mode should be considered.列出具体的损伤机理能造成的多个失效模式列表(比如保温层下腐蚀, 可能带来局部腐蚀或广义腐蚀, 分别得造成针孔型泄漏和大爆裂.

Damage Mechanism→ Damage Modes → Failure Modes→ Failure Scenarios


Damage Mechanism→ Damage Modes → Failure Modes→ Failure Scenarios

Example:

CUI→ Pitting or General Corrosion → Leaks or Bursts → Low COF (water) or High COF (flammable fluid)




d) It is often possible to have two or more damage mechanisms at work on the same piece of equipment or piping component at the same time. Anexample of this could be stress corrosion cracking in combination with generalized or localized corrosion (thinning or pitting).往往是可能有两个或更多的损伤机制, 同时活跃在同一台设备或管道组成件. 如广义/局部腐蚀与应力开裂同时在同个部件活跃.


9.2 Damage Mechanisms 损伤机理

Understanding equipment operation and the interaction with the process environment (both internal and external) and mechanical environment is key to identifying damage mechanisms. Process specialists can provide useful input (such as the spectrum of process conditions, injection points etc.) to aid corrosion specialists in the identification of credible damage mechanisms and rates. For example, understanding that localized thinning may be caused by the method of fluid injection and agitation may be as important as knowing the corrosion mechanism.


Understanding equipment operation and the interaction with the process environment (both internal and external) and mechanical environment is key to identifying damage mechanisms.

了解设备的操作和使用过程中环境(包括内部和外部)的相互作用和机械环境是确认损伤机理的关键点.在这方面, 工艺流程专家能提供有用的信息给以腐蚀专家,可靠的鉴定损伤机理和速率.


equipment operation and the interaction with the process environment


9.3 Failure Modes 失效模式

Once a credible damage mechanisms has been identified, the associated failure mode should also be identified. For example, local thinning could lead to a pinhole leak in the pressure containing boundary. There may be more than one credible failure mode for each damage mechanism. For example, cracking could lead to a through-wall crack with (1) a leak before break scenario or (2) could lead to a catastrophic rupture.

The failure mode will depend on the type of cracking, the geometric orientation of the cracking, the properties of the material of construction, the component thickness, the temperature, and the stress level. Examples of failure modes include: 一旦一个可靠的损伤机制被确定, 相关的故障模式(或多个)也应查明. 故障模式的例子包括

a) pinhole leak,针孔泄漏b) small to moderate leak,小到中等泄漏c) large leak,大量泄漏d) ductile rupture,韧性开口e) brittle fracture.脆性断裂


The risk analysis may, at the discretion of the owner, also include failures other than loss of containment, such as loss of function, tray damage, demister pad failures, coalesce element failures, liquid distribution hardware failures, andheat exchanger tube leaks.

风险分析可在用户的选择下: 除了溶液流失, 还可包括其他故障, 如功能丧失, 托盘的损坏, 除雾器垫故障, 凝聚元件故障, 液体分配系统的硬件故障, 和热交换管的泄

漏


9.4 Accumulated Damage 累积损伤

Damage rates may vary as damage mechanisms progress (i.e. various mechanisms may accelerate or slow or stop completely). In some cases, damage by one mechanism may progress to a point at which a different mechanism takes over and begins to dominate the rate of damage.An evaluation of damage mechanisms and failure modes should include the cumulative effect of each mechanism and/or mode.

损伤机理和失效模式的评价应包括每种机制和/或模式的累积效应


9.5 Tabulating Results 结果制表

The results of a damage mechanisms and failure modes analysis for RBI should indicate:损伤机理和失效模式分析的结果应说明

a) a list of credible damage mechanisms: 可的靠损伤机理列表example: external corrosion; 例如- 外部腐蚀

b) a list of credible damage modes resulting from the damage mechanisms (in 9.5 a): 损伤机理导致的损坏模式example 1: localized thinning,局部变薄example 2: general thinning; 广义变薄

note: Step (b) is optional. Failure modes may be determined directlywithout this intermediate step if desired. 这中间步骤 (b) 是可选的, 如果需要故障模式可以直接确定就可忽略.


c) a ranking of credible failure modes resulting from the damage modes in 9.5 a) and 9.5 b): 顺序排名可靠的失效模式

1. example 1: localized thinning: 局部变薄

- failure mode 1: pinhole leak, - failure mode 2: small leak;

2. example 2: general thinning: 广义变薄

- failure mode 1: pinhole leak, - failure mode 2: small leak, - failure mode 3: large leak, - failure mode 4: rupture.


Documents

Api580 chapter 7 to 9