Hydrocarbon Processing - December 2020 - 47
Plant Design, Engineering and Construction
to manufacture Division 2 vessels. The requirements on materials, fabrication, inspection, testing and marking are the same
for both classes, with minimal changes. Therefore, Class 1 vessels can be treated as vessels that are built to Division 2 quality,
and these vessels can be economical vs. Division 1.
Division 2 rules result in lesser wall thickness vs. Division
1 due to the different theories of failures that they are based
on. With the introduction of Mandatory Appendix 46 in Division 1 (or due to the presence of Code Case 2695), it has now
become on par with Division 2 in terms of design rules. Therefore, with everything else becoming the same, the distinguish-
250
250
200
200
150
150
UTSmin/2.4
UTS/3.0
UTS/3.5
Y/1.5
50
12
10
8
100
6
Division 1
Division 2 Cl.1
Division 2 Cl.2
Thickness reduction
50
4
0
0
75
150
225
Temperature, °C
300
375
0
450
75
150
225
Temperature, °C
300
375
Thickness reduction, %
100
0
16
14
Stress, MPa
Stress, MPa
requiring detailed fatigue analysis (cycles > 1,000).
* Class 1 vessels still require a vessel manufacturer
to develop a manufacturer's design report, but it is
exempted from endorsement by a certifying engineer
unless a detailed fatigue analysis is required by the UDS
and/or design-by-analysis methods are employed.
It is now simpler for fabrication shops that are already authorized to manufacture Division 1 vessels to obtain authorization to manufacture Class 1 vessels without a need to undergo
full assessments amounting to Division 2. This reduces the dependency on only a few fabrication shops that are authorized
2
0
450
FIG. 2. Plot for SA-387 Gr.11 Cl.2 (1.25 Cr-0.5 Mo): (A) y(T), UTS(T) and UTSmin with design margins; (B) allowable stresses and percent reduction
in wall thickness between Division 1 and Division 2 Class 1.
250
250
200
Stress, MPa
150
100
UTSmin/2.4
UTS/3.0
UTS/3.5
Y/1.5
50
75
10
150
8
100
6
Division 1
Division 2 Cl.1
Division 2 Cl.2
Thickness reduction
50
4
0
0
0
12
150
225
Temperature, °C
300
375
0
450
75
150
225
Temperature, °C
300
375
Thickness reduction, %
14
200
Stress, MPa
16
2
0
450
FIG. 3. Plot for SA-387 Gr.22 Cl.2 (2.25 Cr-1 Mo): (A) y(T), UTS(T) and UTSmin with design margins; (B) allowable stresses and percent reduction
in wall thickness between Division 1 and Division 2 Class 1.
16
300
250
250
200
200
14
Stress, MPa
Stress, MPa
12
150
100
8
6
Division 1
Division 2 Cl.1
Division 2 Cl.2
Thickness reduction
100
UTSmin/2.4
UTS/3.0
UTS/3.5
Y/1.5
50
10
150
50
4
0
0
0
75
150
225
Temperature, °C
300
375
450
0
75
150
225
Temperature, °C
300
375
Thickness reduction, %
300
2
0
450
FIG. 4. Plot for SA-542 Ty.D Cl.4a (Cr-Mo-V): (A) y(T), UTS(T) and UTSmin with design margins; (B) allowable stresses and percent reduction
in wall thickness between Division 1 and Division 2 Class 1.
Hydrocarbon Processing | DECEMBER 2020
47
Hydrocarbon Processing - December 2020
Table of Contents for the Digital Edition of Hydrocarbon Processing - December 2020
Contents
Hydrocarbon Processing - December 2020 - Intro
Hydrocarbon Processing - December 2020 - Cover1
Hydrocarbon Processing - December 2020 - Cover2
Hydrocarbon Processing - December 2020 - Contents
Hydrocarbon Processing - December 2020 - 4
Hydrocarbon Processing - December 2020 - 5
Hydrocarbon Processing - December 2020 - 6
Hydrocarbon Processing - December 2020 - 7
Hydrocarbon Processing - December 2020 - 8
Hydrocarbon Processing - December 2020 - 9
Hydrocarbon Processing - December 2020 - 10
Hydrocarbon Processing - December 2020 - 11
Hydrocarbon Processing - December 2020 - 12
Hydrocarbon Processing - December 2020 - 13
Hydrocarbon Processing - December 2020 - 14
Hydrocarbon Processing - December 2020 - 15
Hydrocarbon Processing - December 2020 - 16
Hydrocarbon Processing - December 2020 - 17
Hydrocarbon Processing - December 2020 - 18
Hydrocarbon Processing - December 2020 - 19
Hydrocarbon Processing - December 2020 - 20
Hydrocarbon Processing - December 2020 - 21
Hydrocarbon Processing - December 2020 - 22
Hydrocarbon Processing - December 2020 - 23
Hydrocarbon Processing - December 2020 - 24
Hydrocarbon Processing - December 2020 - 25
Hydrocarbon Processing - December 2020 - 26
Hydrocarbon Processing - December 2020 - 27
Hydrocarbon Processing - December 2020 - 28
Hydrocarbon Processing - December 2020 - 29
Hydrocarbon Processing - December 2020 - 30
Hydrocarbon Processing - December 2020 - 31
Hydrocarbon Processing - December 2020 - 32
Hydrocarbon Processing - December 2020 - 33
Hydrocarbon Processing - December 2020 - 34
Hydrocarbon Processing - December 2020 - 35
Hydrocarbon Processing - December 2020 - 36
Hydrocarbon Processing - December 2020 - 37
Hydrocarbon Processing - December 2020 - 38
Hydrocarbon Processing - December 2020 - 39
Hydrocarbon Processing - December 2020 - 40
Hydrocarbon Processing - December 2020 - 41
Hydrocarbon Processing - December 2020 - 42
Hydrocarbon Processing - December 2020 - 43
Hydrocarbon Processing - December 2020 - 44
Hydrocarbon Processing - December 2020 - 45
Hydrocarbon Processing - December 2020 - 46
Hydrocarbon Processing - December 2020 - 47
Hydrocarbon Processing - December 2020 - 48
Hydrocarbon Processing - December 2020 - 49
Hydrocarbon Processing - December 2020 - 50
Hydrocarbon Processing - December 2020 - 51
Hydrocarbon Processing - December 2020 - 52
Hydrocarbon Processing - December 2020 - 53
Hydrocarbon Processing - December 2020 - 54
Hydrocarbon Processing - December 2020 - 55
Hydrocarbon Processing - December 2020 - 56
Hydrocarbon Processing - December 2020 - 57
Hydrocarbon Processing - December 2020 - 58
Hydrocarbon Processing - December 2020 - 59
Hydrocarbon Processing - December 2020 - 60
Hydrocarbon Processing - December 2020 - 61
Hydrocarbon Processing - December 2020 - 62
Hydrocarbon Processing - December 2020 - 63
Hydrocarbon Processing - December 2020 - 64
Hydrocarbon Processing - December 2020 - 65
Hydrocarbon Processing - December 2020 - 66
Hydrocarbon Processing - December 2020 - 67
Hydrocarbon Processing - December 2020 - 68
Hydrocarbon Processing - December 2020 - 69
Hydrocarbon Processing - December 2020 - 70
Hydrocarbon Processing - December 2020 - 71
Hydrocarbon Processing - December 2020 - 72
Hydrocarbon Processing - December 2020 - 73
Hydrocarbon Processing - December 2020 - 74
Hydrocarbon Processing - December 2020 - 75
Hydrocarbon Processing - December 2020 - 76
Hydrocarbon Processing - December 2020 - 77
Hydrocarbon Processing - December 2020 - 78
Hydrocarbon Processing - December 2020 - 79
Hydrocarbon Processing - December 2020 - 80
Hydrocarbon Processing - December 2020 - 80A
Hydrocarbon Processing - December 2020 - 80B
Hydrocarbon Processing - December 2020 - 81
Hydrocarbon Processing - December 2020 - 82
Hydrocarbon Processing - December 2020 - Cover3
Hydrocarbon Processing - December 2020 - Cover4
Hydrocarbon Processing - December 2020 - GP-1
Hydrocarbon Processing - December 2020 - GP-2
Hydrocarbon Processing - December 2020 - GP-3
Hydrocarbon Processing - December 2020 - GP-4
Hydrocarbon Processing - December 2020 - GP-5
Hydrocarbon Processing - December 2020 - GP-6
Hydrocarbon Processing - December 2020 - GP-7
Hydrocarbon Processing - December 2020 - GP-8
Hydrocarbon Processing - December 2020 - GP-9
Hydrocarbon Processing - December 2020 - GP-10
Hydrocarbon Processing - December 2020 - GP-11
Hydrocarbon Processing - December 2020 - GP-12
Hydrocarbon Processing - December 2020 - GP-13
Hydrocarbon Processing - December 2020 - GP-14
Hydrocarbon Processing - December 2020 - GP-15
Hydrocarbon Processing - December 2020 - GP-16
Hydrocarbon Processing - December 2020 - GP-17
Hydrocarbon Processing - December 2020 - GP-18
Hydrocarbon Processing - December 2020 - GP-19
Hydrocarbon Processing - December 2020 - GP-20
Hydrocarbon Processing - December 2020 - GP-21
Hydrocarbon Processing - December 2020 - GP-22
Hydrocarbon Processing - December 2020 - GP-23
Hydrocarbon Processing - December 2020 - GP-24
Hydrocarbon Processing - December 2020 - GP-25
Hydrocarbon Processing - December 2020 - GP-26
Hydrocarbon Processing - December 2020 - GP-27
Hydrocarbon Processing - December 2020 - GP-28
Hydrocarbon Processing - December 2020 - GP-29
Hydrocarbon Processing - December 2020 - GP-30
Hydrocarbon Processing - December 2020 - GP-31
Hydrocarbon Processing - December 2020 - GP-32
Hydrocarbon Processing - December 2020 - GP-33
Hydrocarbon Processing - December 2020 - GP-34
Hydrocarbon Processing - December 2020 - GP-35
Hydrocarbon Processing - December 2020 - GP-36
Hydrocarbon Processing - December 2020 - GP-37
Hydrocarbon Processing - December 2020 - GP-38
Hydrocarbon Processing - December 2020 - GP-39
Hydrocarbon Processing - December 2020 - GP-40
Hydrocarbon Processing - December 2020 - GP-41
Hydrocarbon Processing - December 2020 - GP-42
Hydrocarbon Processing - December 2020 - GP-43
Hydrocarbon Processing - December 2020 - GP-44
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