Input variables
Generic variables
These variables can be found in mostly all reports as input variables
Gas infrastructure
Location of the facility near which the gas infrastructure is situated.
- Underground, except a station
- In a tunnel
- Station
Maximum Design Factor – fo
Factor for restricting the allowable stress. The value can be chosen smaller, but not larger.
Design Pressure – DP
Pressure assumed to be present in the component according to the design terms
Design Temperature – θ
Temperature assumed to be present in the component according to the design terms
Material (header/branch)
Name of selected material used for the construction of the component
Specific variables
These variables are component specific.
Outside Diameter branch and header – do, D
Outside diameter of the attached part. The diameter runs from the outside of the wall to the opposite outside of the wall, through the center of the circle.
Inside Diameter – din
Inside diameter at the top.
Shoulder Diameter – D2
Largest outside diameter.
Diameter hole in header – D3
Internal diameter opening between header and branch. Equal to the inside diameter at the bottom.
Overall height branch – H0
Height from top to bottom.
Height at shoulder to branch – H1
Height from the top to the largest outside diameter
Height at inside beveled area – H2
Height from the bottom to the smallest inside diameter.
Height at welding area header – H3
Available height at bottom for welding
Gap between header and weldolet – Gap
Clearance distance at bottom for welding
Nominal Thickness Header – Tsn
Thickness ‘as is’, meaning it is the design thickness taking into account corrosion and tolerance.
Corrosion – Ca, Cah
Amount of thickness that accounts for the possible effects of corrosion.
Tolerance header – tolh
Tolerance in thickness for production
Strength reduction coefficient header – zh
Effectiveness of the strength, depending on whether joints are seamless, welded, or expected to perform worse than the base material properties.
Calculated Values
Allowable Operating Stress – S, Ss
Stress in the component at which it is still allowed (without failure) to use the component. The additional h indicates the same variable but for the header.
Allowable stress at 20 °C – St, Sst
Stress in the component at which it is still allowed (without failure) to use the component at 20 °C ambient temperature. The additional suffix s indicates the same variable but for the header.
Stress ratio – S/Ss, St/Sst
Ratio of the allowable stresses in the branch and the header
Reinforcement limit header direction – L
Length from the branch outside diameter to the end of the header reinforcement zone.
Reinforcement limit branch direction – H
Length from the header outside diameter to the end of the branch reinforcement zone.
Material area header – A0
Cross-sectional area of header material between reinforcement limits.
Material area branch – A1
Cross-sectional area of branch material between reinforcement limits.
Pressure area header – Ap0
Cross-sectional area with pressure in header between reinforcement limits.
Pressure area branch – Ap1
Cross-sectional area with pressure in branch between reinforcement limits.
Total pressure area – Ap
Total cross-sectional area with pressure in header and branch between reinforcement limits.
Pressure force – Fpa
Total force of the design pressure on the total pressure area.
Maximum allowable pressure force – Fpamax
Maximum allwable force of the design pressure on the total pressure area.
Minimum strength reduction coefficient at opening – zmin
Minimum required effectiveness of the strength in the opening.
Strength reduction coefficient at opening – z
Effectiveness of the strength in the opening.
Maximum Allowable Working Pressure – MAWP
The maximum pressure at which the component can be used in operation. This value should be larger than the design pressure.
Design margin – DP/MAWP
Ratio of the design pressure to MAWP
Maximum Allowable Test Pressure – MATP
The maximum pressure at which the component should be tested and survive.
Scope errors
Design pressure is out of scope: minimum operating pressure > 16 bar.
This code determines a minimum pressure.
Design temperature is out of scope: required -40 °C ≤ T ≤ 120 °C.
This code determines a minimum and maximum temperature.
Design factor is too large: required is fo ≤ fomax (see 7.2).
This code determines a maximum design factor.
No header pipe dimensions specified.
A header pipe is needed for the calculations.
Wall thickness header is out of scope according paragraph 7.9.2 Table 1.
This code determines for headers a minimum thickness.
Wall thickness branch is out of scope according paragraph 7.9.2 Table 1.
This code determines for branches a minimum thickness.
Errors
Can’t find material ‘MaterialName’ in database
Material could not be found in database. Select an existing material name, or select another material via the material selection window.
Insufficient wall thickness for header
Wall thickness is insufficient to bear the applied loads. Increase the wall thickness of the header.
Insufficient reinforcement area.
Reinforcement area is too small. Increase the reinforcement area or thickness.
Insufficient strength reduction coefficient for header: required is z ≥ zmin.
Strength reduction coefficient is too small. Increase the reinforcement area or thickness.