安全仪表系统简介

0.01 - 0.001
operating and monitoring functions 运行和检测功能 2004-04-28 SIS (“Class A U.Schuenemann
How to meet ―SIL‖ requirements 如何满足“SIL‖要求
1.
Right Instruments: from BASF standard list (field proven) or certified 仪表正确 : 来自巴斯夫标准清单或核准者 (SIL 2, TUV certificate,…) Devices without systematic design or
85 % 现场仪表
to Failure Probability (PFD):对故障概率
的影响因素
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Commissioning test of E&I SIS
2004-04-28 U.Schuenemann
―SIL‖ requirements SIS SIS的 For SIS: international andfor BASF standards request SIL 2 or SIL 3. “SIL‖要求
E&I Safety Instrumented Systems (SIS) 电仪安全仪表系统(SIS) 介绍
2004-04-28 Ulrich Schuenemann – BYC Nanjing
BYC 南京 尤瑞奇 • 舒曼
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Commissioning test of E&I SIS
CTA Department
Active error – triggers off the safety function for no reason – plant is switched back to safe operation – reduction of production availability ⁃有源故障 -无缘无故触发安全功能 -装置切回到安全运行 -生产运行可用率降低
2004-04-28 U.Schuenemann
There are different E&I functions 电仪功能各不相同

Control loops DCS Monitoring functions DCS
控制回路

检测功能

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Interlocks needed for smooth operation 2004-04-28 DCS, (ESD) Commissioning test of E&I SIS U.Schuenemann
A A/B B C B B C D D E E F E E F F
P2 (1/100y) P3 (1/1.000y)
SEVERITY 严重性 E P4 F F F S1 Potential for one or more fatalities (<1/10.000y) S2 Potential for one or more serious injuries (irreversible) S3 Potential for one or more lost time injuries S4 Potential for minor injuries, or irritation
failure rates l : Pf (t) = (1 – e-l t ) 故障概率(对功能而言).恒定故障率 l : Pf (t) = (1 – e-l t ) PFD Probability of Failure on Demand 2004-04-28 10 test of E&I SIS U.Schuenemann = P (t)Commissioning , time averaged over test interval TI
What are E&I S.I.S. S.I.S?
什么是电仪
E&I Safety Instrumented Systems (S.I.S.): 电仪安全仪表系统

S.I.S. prevent
– personnel
安全仪表系统用于防止：
人身伤害或 环境破坏
injury – environmental damage
caused by a not tolerable fault state of the plant
3
由装置的不可接受的故障所造成
Commissioning test of E&I SIS
2004-04-28 U.Schuenemann
Classification of E&I functions 电仪 功能的分类
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E&I SIS can be used for ―risk class B and C‖. 2004-04-28 电仪SIS 可用于 “ Bof 级和 C级风险” Commissioning test E&I SIS U.Schuenemann
Example: E&I Safety Review 2 Checklist 实例: 电仪安全审查2检查清单
PFD – Probability of Failure on Demand PFD—指令故障概率
Pf (t) = (1 – e-l t )
Probability Pf(t) for finding equipment in dangerous time average 时间平均值 fault state after time t has PFD Probability of since passed Failure on demand last functional PFD—指令故障概率 test PFD depends on failure rate of equipment AND test interval. 自上次功能试验以 PFD取决于设备AND试验间隔的故障率 来经过时间 t 后 , 2004-04-28 发现设备处在危 11 Commissioning test of E&I SIS U.Schuenemann

PFD-calculation for more complex configurations (2oo3 etc. ) can be done using simple statistical models: Good for comparing different configurations. 用简单的统计模型可进行较复杂的配置(2003等)的PFD计算 For SIS: PFD of field domain and control domain must be added.

Calculation PFDequipment PFD 的计算 PFD calculation of an of individual easy, if you have
–
test interval – failure rate (given by supplier) – 如有试验间隔和故障率(供货方提供), 则某个设备的PFD计算就不难
fault : PFD “Probability of Failure on Demand” 无源故障的时间平均可能性: PFD”指令故障的可能性“
2004-04-28 U.Schuenemann
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Commissioning test of E&I SIS
Components of a SIS Field 现场

对于SIS: 必须加上磁场域和控制域的PFD
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PFD
ຫໍສະໝຸດ Baidu
= PFD
Commissioning test of E&I SIS
+ PFD
+ PFD
2004-04-28 U.Schuenemann
Calculation of PFD – the problems… PFD的计算—问题…

(failsafe PLC) 15 % 逻辑解答器 Contribution (故障保护PLC)
PFD data for field instruments usually not very reliable (not experimentally verified for chemical environment). 用于现场仪表的PFD数据通常不是很可靠(对于化学 环境未经试验验证 ). Logic Solver Field Instruments
对安全功能产生不利影响
Passive error 无源故障 – inhibits the required safety function – plant continues operation although it should be switched off – impactingprobability the process Time-averaged for a safety passive
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Commissioning test of E&I SIS
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Probability严 重性概率 P0 (>=1/y) P1 (1/10y)
Definition of SIS: Safety Review step 2 Severity S2 S3 S4 SIS 的定义: S1安全审查步骤 2
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Commissioning test of E&I SIS
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Passive Faults of sensors and actuators restriction orifice, deformed by flow 传感器和致动器的无源故障
限流孔板 限流孔板 限流孔, 流量造成的变形
2004-04-28 U.Schuenemann
TI
Test Interval between functional tests of SIS, Some time mathematics… 一些算法 needed to discover dangerous faults … SIS功能测试之间的时间间隔, 发现危险故 障需要的时间 MTBF Mean Time Between Failure of an equipment 设备故障之间的平均时间 l = 1/ MTBF failure rate 故障率 Pf (t) constant Probability of failure (to function). For
manufacturing errors which can lead to common failure of redundant channels at the same time.
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Failures of a S.I.S.
Failure 故障
S.I.S 的故障 no adverse effect on
the safety function 对安全功能无不利影响
adversely affecting the safety function
lost control valve plug 调节阀阀塞 ,空穴造成的损坏 mass flow meter after pressure pulse 压力脉冲下游的 质量流量计
control valve plug, damaged by cavitation
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Commissioning test of E&I SIS
Redundant sensors 冗余的传感器
SIS的组分
Rack Room 机柜间 Shut-Down System 停车系统 Logic in Failsafe PLC or Hardwired system 在故障安全型可编程 控制器或硬接线系统 中的逻辑
Instrument air supply 仪表气源 Valve 阀门 Solenoid valve 电磁阀
对于SIS: 国际标准和巴斯夫标准要求SIL2 或 SIL3.
Safety Integrity Level (SIL) 安全一体化水 平 1
Probability of Failure on Demand (PFD) 指令故障概率
0.10 - 0.01
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Commissioning test of E&I SIS