API RP 581 - 3rd Ed.2016 - Add.2-2020 - Risk-Based Inspection Methodology
5-26 API RECOMMENDED PRACTICE 581Table 4.8⎯Release Hole Sizes and Areas⎯Storage Tank BottomsRelease HoleNumberRelease Hole Size1 SmallRelease PreventionBarrier?Range of HoleDiameters(inch)Release Hole Diameter(inch)Yes 0 – 1/8 d1= 0.125No 0 – ½ d1= 0.502 Medium3 Large4 RuptureNA 0NA 0NA 0NA 0Yes > 1/8No > 1/2d2= 0d3= 0D tank⎛ ⎞d4 = 12⎜ ⎟⎝ 4 ⎠Table 4.8M⎯Release Hole Sizes and Areas⎯Storage Tank BottomsRelease HoleNumberRelease Hole Size1 SmallRelease PreventionBarrier?Range of HoleDiameters(mm)Release Hole Diameter(mm)Yes 0 – 3.175 d1= 3.175No 0 – 12.7 d1= 12.72 Medium3 Large4 RuptureNA 0NA 0NA 0NA 0Yes > 3.175No > 12.7d2= 0d3= 0D tank⎛ ⎞d4 = 1000⎜ ⎟⎝ 4 ⎠
RISK-BASED INSPECTION METHODOLOGY, PART 5—SPECIAL EQUIPMENT 5-27Table 4.9⎯Number of Release Holes as a Function of Storage Tank DiameterStorage Tank Diameter(m (ft))Number of Release Holes with or Without a Release Prevention BarrierSmall Medium Large30.5 (100) 1 0 061.0 (200) 4 0 091.4 (300) 9 0 0NOTE For intermediate storage tank diameters, the number of small release holes may be calculated using thefollowing equation where the function nint() is defined as the nearest integer. For example, nint(3.2)=3, nint(3.5)=4,and nint(3.7)=4.n rh ,12⎡ ⎡⎛D ⎞ ⎤ ⎤= max ⎢nint ⎢⎜ ⎟ ⎥, 1⎥⎢ ⎢ C⎣⎝36 ⎠ ⎥⎦⎥⎣⎦Figures1Dike Area6TankSurface Water2OnsiteOffsite3Subsurface Soil4Ground Water5Figure 4.1⎯Storage Tank Consequence
- Page 525 and 526: RISK-BASED INSPECTION METHODOLOGY,
- Page 527 and 528: RISK-BASED INSPECTION METHODOLOGY,
- Page 529 and 530: RISK-BASED INSPECTION METHODOLOGY,
- Page 531 and 532: RISK-BASED INSPECTION METHODOLOGY,
- Page 533 and 534: RISK-BASED INSPECTION METHODOLOGY,
- Page 535 and 536: RISK-BASED INSPECTION METHODOLOGY,
- Page 537 and 538: RISK-BASED INSPECTION METHODOLOGY,
- Page 539 and 540: RISK-BASED INSPECTION METHODOLOGY,
- Page 541 and 542: CONTENTS1 GENERAL………………
- Page 543 and 544: 3.B-2 API RECOMMENDED PRACTICE 5813
- Page 545 and 546: 3.B-4 API RECOMMENDED PRACTICE 581T
- Page 547 and 548: PART 5SPECIAL EQUIPMENT5-1
- Page 549 and 550: Consequence of Failure Methodology
- Page 551 and 552: Risk-Based Inspection MethodologyPa
- Page 553 and 554: RISK-BASED INSPECTION METHODOLOGY,
- Page 555 and 556: RISK-BASED INSPECTION METHODOLOGY,
- Page 557 and 558: RISK-BASED INSPECTION METHODOLOGY,
- Page 559 and 560: RISK-BASED INSPECTION METHODOLOGY,
- Page 561 and 562: RISK-BASED INSPECTION METHODOLOGY,
- Page 563 and 564: RISK-BASED INSPECTION METHODOLOGY,
- Page 565 and 566: RISK-BASED INSPECTION METHODOLOGY,
- Page 567 and 568: RISK-BASED INSPECTION METHODOLOGY,
- Page 569 and 570: RISK-BASED INSPECTION METHODOLOGY,
- Page 571 and 572: RISK-BASED INSPECTION METHODOLOGY,
- Page 573 and 574: RISK-BASED INSPECTION METHODOLOGY,
- Page 575: RISK-BASED INSPECTION METHODOLOGY,
- Page 579 and 580: RISK-BASED INSPECTION METHODOLOGY,
- Page 581 and 582: RISK-BASED INSPECTION METHODOLOGY,
- Page 583 and 584: RISK-BASED INSPECTION METHODOLOGY,
- Page 585 and 586: RISK-BASED INSPECTION METHODOLOGY,
- Page 587 and 588: RISK-BASED INSPECTION METHODOLOGY,
- Page 589 and 590: RISK-BASED INSPECTION METHODOLOGY,
- 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,
5-26 API RECOMMENDED PRACTICE 581
Table 4.8⎯Release Hole Sizes and Areas⎯Storage Tank Bottoms
Release Hole
Number
Release Hole Size
1 Small
Release Prevention
Barrier?
Range of Hole
Diameters
(inch)
Release Hole Diameter
(inch)
Yes 0 – 1/8 d
1
= 0.125
No 0 – ½ d
1
= 0.50
2 Medium
3 Large
4 Rupture
NA 0
NA 0
NA 0
NA 0
Yes > 1/8
No > 1/2
d
2
= 0
d
3
= 0
D tank
⎛ ⎞
d4 = 12⎜ ⎟
⎝ 4 ⎠
Table 4.8M⎯Release Hole Sizes and Areas⎯Storage Tank Bottoms
Release Hole
Number
Release Hole Size
1 Small
Release Prevention
Barrier?
Range of Hole
Diameters
(mm)
Release Hole Diameter
(mm)
Yes 0 – 3.175 d
1
= 3.175
No 0 – 12.7 d
1
= 12.7
2 Medium
3 Large
4 Rupture
NA 0
NA 0
NA 0
NA 0
Yes > 3.175
No > 12.7
d
2
= 0
d
3
= 0
D tank
⎛ ⎞
d4 = 1000⎜ ⎟
⎝ 4 ⎠
Change language