Specifies the stress range reduction factor for most piping codes.
B31.1
Stress range reduction factor is obtained from equation 1c. Consult the applicable piping code for methods of combining cycle life data where several thermal states exist and where the number of thermal cycles is high. The software assumes a value of one if you do not type a value.
B31.3
Stress range reduction factor is obtained from equation 1c corresponding to Fig 302.3.5. If certain criteria are met, then the stress range reduction factor can exceed 1.0. The number of cycles can be specified in this box for B31.3. This allows CAESAR II to compute the cyclic reduction factor according to equation 1c.
B31.4, B31.4 Chapter XI
Stress range reduction factor is obtained from the equation given in Section 403.3.2. The number of cycles can also be specified in this box for B31.4 which allows CAESAR II to compute the cyclic reduction factor according to the equation. The fatigue factor cannot exceed 1.2.
B31.4 Chapter IX
Not used.
B31.8
Stress range reduction factor is obtained from the equation given in Section 833.8(b). The number of cycles can be specified in this box for B31.8 which allows CAESAR II to compute the cyclic reduction factor according to this equation.
B31.8 CHAPTER VIII
Not used.
B31.9
References B31.1 for detailed stress analysis. For more information, see Paragraph 919.4.1.b.
CODETI
Called U in the code.
NORWEGIAN
Called fr in the code. This value can be as high as 2.34.
DNV
Material ultimate tensile strength at temperature.
CAN Z662
F1 = L - The location factor from Table 4.2
F2 = T - The temperature derating factor from Table 4.4
For F1 = L:
|
Application |
CLASS 1 |
CLASS 2 |
CLASS 3 |
CLASS 4 |
|---|---|---|---|---|
|
Gas (non-sour) |
||||
|
General & Cased crossings |
1.000 |
0.900 |
0.700 |
0.550 |
|
Roads |
0.750 |
0.625 |
0.625 |
0.500 |
|
Railways |
0.625 |
0.625 |
0.625 |
0.500 |
|
Stations |
0.625 |
0.625 |
0.625 |
0.500 |
|
Other |
0.750 |
0.750 |
0.625 |
0.500 |
|
Gas (sour service) |
||||
|
General & Cased crossings |
0.900 |
0.750 |
0.625 |
0.500 |
|
Roads |
0.750 |
0.625 |
0.625 |
0.500 |
|
Railways |
0.625 |
0.625 |
0.625 |
0.500 |
|
Stations |
0.625 |
0.625 |
0.625 |
0.500 |
|
Other |
0.750 |
0.750 |
0.625 |
0.500 |
|
HVP |
||||
|
General & Cased crossings |
1.000 |
0.800 |
0.800 |
0.800 |
|
Roads |
0.800 |
0.800 |
0.800 |
0.800 |
|
Railways |
0.625 |
0.625 |
0.625 |
0.625 |
|
Stations |
0.800 |
0.800 |
0.800 |
0.800 |
|
Other |
0.800 |
0.800 |
0.800 |
0.800 |
|
LVP |
||||
|
Uncased railway crossings |
0.625 |
0.625 |
0.625 |
0.625 |
|
All others |
1.000 |
1.000 |
1.000 |
1.000 |
Class 1 - Location areas containing ten or fewer dwelling units intended for human occupancy
Class 2 - Location areas containing 11 to 46 dwelling units intended for human occupancy OR
-
Buildings with more than 20 persons
-
Outside areas with more than 20 persons
-
Industrial installations
Class 3 - Location areas with more than 46 dwelling units intended for human occupancy OR institutions where rapid evacuation may be difficult
Class 4 - Location areas where buildings intended for human occupancy have 4 or more stories.
For F2 = T:
|
Temperature |
Derating Factor T |
|---|---|
|
up to 120 (C) |
1.00 |
|
150 |
0.97 |
|
180 |
0.93 |
|
200 |
0.91 |
|
230 |
0.87 |
F3 through F9 are not used.
CAN Z662 Chapter 11
F1 - Not used.
F2 = T - Temperature derating factor obtained from Table 4.4
F3 = - FA design factor for Condition A from Table 11.1, column A
F4 = - FB design factor for Condition B from Table 11.1, column B
F5 through F9 are not used.
BS 806
Mean stress to failure in design life at design temperature. F1, F2, ... F9. This value corresponds to the nine possible thermal states.
FDBR
Identical to B31.1, unless you type the expansion coefficients directly instead of temperatures. In that case, the software cannot determine Ehot. In this case, type a value of 1.0 in the FAC box and use these boxes to specify the product of f * Ehot / Ecold for each temperature case.
SWEDISH METHOD 1
Creep rupture stress at temperature. F1, F2 ... F9. This value corresponds to the nine possible thermal states.
STOOMWEZEN
Creep related material properties as follows:
-
F1 = Rrg - Average creep stress to produce 1% permanent set after 100,000 hours at temperature (vm).
-
F2 = Rmg - Average creep tensile stress to produce rupture after 100,000 hours at temperature (vm).
-
F3 = Rmmin - Minimum creep tensile stress to produce rupture after 100,000 hours at temperature (vm).
BS 7159
Fatigue factor Kn. This value is used inversely compared to other codes so that its value is greater than 1.0. Kn is calculated as follows:
Kn = 1 + 0.25(As/sn) (log10(n) - 3)
Where:
As = stress range during fatigue cycle
σn = Maximum stress during fatigue cycle
n = number of stress cycles during design life
UKOOA
Ratio r from the material UKOOA idealized allowable stress envelope. This ratio is defined as sa(0:1)/sa(2:1) as shown on the figure below. One value should be given for each of the operating temperature cases.
IGE/TD/12
UTS value.
EN-13480
Stress range reduction factor taken from Table 12.1.3-1 (which matches the B31.1 table above) or computed from equation 12.1.3-4. You can specify the number of cycles in this box for EN-13480. This allows CAESAR II to compute the cyclic reduction factor according to equation 12.1.3-4.
GPTC/Z380
Not used.
PD-8010 (Part 1 & Part 2)
Not used.
ISO 14692
F is used in a different way. See the Reference for ISO 14692.
HPGSL
Stress range reduction factor at design temperature.
JPI
Stress range reduction factor at design temperature.