In CAESAR II, a load case is a group of piping system loads that are analyzed together and occur at the same time. An example of a load case is an operating analysis composed of the thermal, deadweight, and pressure loads together. Another example is an asinstalled analysis of deadweight loads alone.
A load case can also be composed of the combinations of the results of other load cases. For example, a load case can be the difference in displacements between the operating and installed cases.
No matter what the contents of the load case, it always produces a set of reports, which list restraint loads, displacements and rotations, internal forces, moments, and stresses. Because of piping code definitions for calculation methods and/or allowable stresses, CAESAR II also tags load cases with a stress type. For example, the combination mentioned previously might be tagged as an expansion stress case (EXP).
Piping System Loads
The piping system loads that compose the basic noncombination load sets relate to various input items found on the Classic Piping Input dialog box. The following tables list the individual load set designations, their names and the input items, which make them available for analysis.
Designation 
Name 
Input items which activate this load case 

W 
Deadweight 
Pipe Weight, Insulation Weight, Refractory Weight, Cladding Weight, Fluid Weight, Rigid Weight 
WNC 
Weight No fluid Contents 
Pipe Weight, Insulation Weight, Refractory Weight, Cladding Weight, Rigid Weight 
WW 
Water Weight 
Pipe Weight, Insulation Weight, Refractory Weight, Cladding Weight, Waterfilled Weight, Rigid Weight (usually used for Hydro Test) 
T1 
Thermal Set 1 
Temperature #1 
T2 
Thermal Set 2 
Temperature #2 
T3 
Thermal Set 3 
Temperature #3 
T9 
Thermal Set 9 
Temperature #9 
P1 
Pressure Set 1 
Pressure #1 
P2 
Pressure Set 2 
Pressure #2 
P3 
Pressure Set 3 
Pressure #3 
P9 
Pressure Set 9 
Pressure #9 
HP 
Hydrostatic Test Pressure 
Hydro Pressure 
D1 
Displacements Set 1 
Displacements (1st Vector) 
D2 
Displacements Set 2 
Displacements (2nd Vector) 
D3 
Displacements Set 3 
Displacements (3rd Vector) 
D9 
Displacement Set 9 
Displacements (9th Vector) 
F1 
Force Set 1 
Forces/Moments (1st Vector) 
F2 
Force Set 2 
Forces/Moments (2nd Vector) 
F3 
Force Set 3 
Forces/Moments (3rd Vector) 
F9 
Force Set 9 
Forces/Moments (9th Vector) 
WIN1 
Wind Load 1 
Wind Shape Factor 
WIN2 
Wind Load 2 
Wind Shape Factor 
WIN3 
Wind Load 3 
Wind Shape Factor 
WIN4 
Wind Load 4 
Wind Shape Factor 
WAV1 
Wave Load 1 
Wave Load On 
WAV2 
Wave Load 2 
Wave Load On 
WAV3 
Wave Load 3 
Wave Load On 
WAV4 
Wave Load 4 
Wave Load On 
U1 
Uniform Loads 
Uniform Loads (1st Vector) 
U2 
Uniform Loads 
Uniform Loads (2nd Vector) 
U3 
Uniform Loads 
Uniform Loads (3rd Vector) 
CS 
Cold Spring 
Material # 18 or 19 
H 
Hanger Initial Loads 
Hanger Design or Prespecified Hangers 
Available piping system loads display on the left side of the Static Analysis dialog box.
Basic Load Cases
Load cases are comprised of one or more major load types as defined in the input. Major load cases are load cases that require a solution to the matrix equation [K]{x} = {f}.
For example:

W+T1+P1+F1 (OPE) is a major load case

W+P1+F1 (SUS) is a major load case
Basic load cases can consist of a single load, such as WNC for an asinstalled weight analysis. A basic load can also include several loads added together, such as W+T1+P1+D1+F1 for an operating analysis. The stress type categories sustained (SUS), expansion (EXP), occasional (OCC), operating (OPE), and fatigue (FAT) are specified at the end of the load case definition. The definition of the two examples is: WNC (SUS) and W+T1+P1+D1+H (OPE). Enter each basic load case in this manner.
Load components, such as W, T1, D1, WIN1, can be preceded by scale factors such as 2.0, 0.5, and so forth. Likewise, you can precede references to previous load cases by scale factors when you build combination cases.
This provides you with several benefits.

If one loading is a multiple of the other (such as Safe Shutdown Earthquake being two times Operating Basis Earthquake) you must type only one loading in the Classic Piping Input dialog box. You can use this loading in a scaled or unscaled form in the Static Analysis  Load Case Editor dialog box.

If a loading can be directionally reversible, such as wind or earthquake, you must type only one loading in the Classic Piping Input dialog box. You can use this loading preceded by a + or a  to switch the direction.

Load Rating Design Factor (LRDF) methods can be implemented by scaling individual load components by their riskdependent factors. For example:
1.05W + 1.1T1+1.1D1+1.25 WIN1
You can select the stress type from the list on each line.
Combination Load Cases
You can combine the results of the basic load cases by using combination load cases. Always type these combinations after the last of the basic load cases. Designate combinations of basic load cases by using the prefix L1, L2, and so on.
Algebraic combination load cases are combinations of previouslysolved major load cases. For example:

L1L2 (EXP) is a combination case which combines the displacements, forces, and stresses using a combination method that you select.

L4+L6+L8 (OCC) is a combination case which combines the displacements, forces, and stresses using a combination method that you select.
The + and  signs are unary operators/sign of multiplier. If no value precedes the load for major load cases or the load case for combination cases, then the multiplier is +1.0 or 1.0. If a value precedes the load or the load case, then the multiplier is +value or value.
You must specify the expected number of load cycles for all load cases with stress type fatigue (FAT).
The following family of load cases provides an example of algebraic combinations.
Load Case 



1 
W+T1+P1+H+0.67CS (OPE) 
Hot operating. The 0.67scale factor takes credit only for 2/3 of the cold spring. 
2 
W1+P1+H+0.67CS(OPE) 
Cold operating with cold spring included. 
3 
W1+P1+H(SUS) 
Traditional sustained case. 
4 
WIN1(OCC) 
Wind case. This will be manipulated later to represent average wind 1X, maximum wind 2X (in the positive and negative directions). 
5 
L1L2(EXP) 
Traditional cold to hot expansion case. Use L for load, rather than DS. 
6 
L1L2(FAT) 
Same case evaluated for fatigue at 10,000 cycles. 
7 
L1+L4(OPE) 
Hot operating with average wind (in positive direction). 
8 
L1L4(OPE) 
Hot operating with average wind (in negative direction). 
9 
L1+2L4(OPE) 
Hot operating with maximum wind (in positive direction). 
10 
L12L4(OPE) 
Hot operating with maximum wind (in negative direction). 
11 
L2+L4(OPE) 
Cold operating with average wind (in positive direction). 
12 
L2L4(OPE) 
Cold operating with average wind (in negative direction). 
13 
L2+2L4(OPE) 
Cold operating with maximum wind (in positive direction). 
14 
L22L4(OPE) 
Cold operating with maximum wind (in negative direction). 
15 
L3+L4(OCC) 
Occasional stress case, sustained plus average wind. 
16 
L3+2L4(OCC) 
Occasional stress case, sustained plus maximum wind. 
17 
L9+L10+L11+L12(OPE) 
Maximum restraint load case. The combination option should be MAX. 
CAESAR II permits the specification of up to 999 load cases for analysis. Copy the model to a new file to specify the additional load cases if more cases are required.