API RP 581 - 3rd Ed.2016 - Add.2-2020 - Risk-Based Inspection Methodology
5-92 API RECOMMENDED PRACTICE 581.8000.7000.6000.5000POFOD.4000MildModerateSevere.3000.2000.1000.00000 2 4 6 8 10 12 14 16 18 20YearsFigure 5.3—Default Conventional PRV Fail to Open on Demand Weibull Curves.9000.8000MildModerateSevere.7000.6000POL.5000.4000.3000.2000.1000.00000 2 4 6 8 10 12 14 16 18 20YearsFigure 5.4—Default Leakage Failure Rate for Conventional PRVs
RISK-BASED INSPECTION METHODOLOGY, PART 5—SPECIAL EQUIPMENT 5-9354.543.5Actual Failure DataAdjusted CurveFailure Rate (%)32.52Failure rate is constant with overpressure1.510.501 1.5 2 2.5 3 3.5 4Overpressure Ratio (Pop Pressure/Set Pressure)Figure 5.5—PRD Failure Rate as a Function of Overpressure.6000.5000POFOD.4000.3000SevereModified SevereEffect of Environmental ModifierModified POFOD Curve.2000Default POFOD Curve.1000.00000 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15Years In ServiceFigure 5.6—Effect of Environmental Factors on PRD Weibull Curves
- Page 591 and 592: RISK-BASED INSPECTION METHODOLOGY,
- Page 593 and 594: RISK-BASED INSPECTION METHODOLOGY,
- Page 595 and 596: RISK-BASED INSPECTION METHODOLOGY,
- Page 597 and 598: RISK-BASED INSPECTION METHODOLOGY,
- Page 599 and 600: RISK-BASED INSPECTION METHODOLOGY,
- Page 601 and 602: RISK-BASED INSPECTION METHODOLOGY,
- Page 603 and 604: RISK-BASED INSPECTION METHODOLOGY,
- Page 605 and 606: RISK-BASED INSPECTION METHODOLOGY,
- Page 607 and 608: RISK-BASED INSPECTION METHODOLOGY,
- Page 609 and 610: RISK-BASED INSPECTION METHODOLOGY,
- Page 611 and 612: RISK-BASED INSPECTION METHODOLOGY,
- Page 613 and 614: RISK-BASED INSPECTION METHODOLOGY,
- Page 615 and 616: RISK-BASED INSPECTION METHODOLOGY,
- Page 617 and 618: RISK-BASED INSPECTION METHODOLOGY,
- Page 619 and 620: RISK-BASED INSPECTION METHODOLOGY,
- Page 621 and 622: RISK-BASED INSPECTION METHODOLOGY,
- Page 623 and 624: RISK-BASED INSPECTION METHODOLOGY,
- Page 625 and 626: RISK-BASED INSPECTION METHODOLOGY,
- Page 627 and 628: RISK-BASED INSPECTION METHODOLOGY,
- Page 629 and 630: RISK-BASED INSPECTION METHODOLOGY,
- Page 631 and 632: RISK-BASED INSPECTION METHODOLOGY,
- Page 633 and 634: RISK-BASED INSPECTION METHODOLOGY,
- Page 635 and 636: RISK-BASED INSPECTION METHODOLOGY,
- Page 637 and 638: RISK-BASED INSPECTION METHODOLOGY,
- Page 639 and 640: RISK-BASED INSPECTION METHODOLOGY,
- Page 641: RISK-BASED INSPECTION METHODOLOGY,
- Page 645 and 646: CONTENTS5.A.1 General .............
- Page 647 and 648: 5.A-2 API RECOMMENDED PRACTICE 5815
- Page 649 and 650: 5.A-4 API RECOMMENDED PRACTICE 581
- Page 651 and 652: 5.A-6 API RECOMMENDED PRACTICE 5815
5-92 API RECOMMENDED PRACTICE 581
.8000
.7000
.6000
.5000
POFOD
.4000
Mild
Moderate
Severe
.3000
.2000
.1000
.0000
0 2 4 6 8 10 12 14 16 18 20
Years
Figure 5.3—Default Conventional PRV Fail to Open on Demand Weibull Curves
.9000
.8000
Mild
Moderate
Severe
.7000
.6000
POL
.5000
.4000
.3000
.2000
.1000
.0000
0 2 4 6 8 10 12 14 16 18 20
Years
Figure 5.4—Default Leakage Failure Rate for Conventional PRVs
Change language