# 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
Name of selected material used for the construction of the component

## Specific variables

These variables are component specific

Outside Diameter – 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.
Nominal Thickness – Tn
Thickness ‘as is’, meaning it is the design thickness taking into account corrosion and tolerance.
Corrosion – Ca
Amount of thickness that accounts for the possible effects of corrosions.
Tolerance – tol
Tolerance in thickness for production
Strength reduction coefficient – z
Effectiveness of the strength, depending on whether joints are seamless, welded, or expected to perform worse than the base material properties
Hemispherical Cap

# Calculated Values

Yield strength at operating temperature – Rt
Stress in the component at which the component starts to plastically deform at operating temperature.
Minimum yield strength at 20 °C – Rta
Stress in the component at which the component starts to plastically deform at 20 °C ambient temperature
Allowable Stress at Temperature – S
Stress in the component at which it is still allowed (without failure) to use the component
Allowable stress at 20 °C – St
Stress in the component at which it is still allowed (without failure) to use the component at testing condition
Inside Diameter – Di
Outside Diameter − 2 × Thickness
Nominal Required Thickness – Trn
Based on the input, this is the calculated thickness that is required to sustain the loads. The nominal value should be smaller than the nominal design thickness.
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 fofomax (see 7.2).
This code determines a maximum design factor.
Dish thickness is out of scope according paragraph 7.9.2 Table 1.
This code determines for heads a minimum thickness.
Dish thickness is out of scope: required Tdn ≥ 4 mm.
This code determines for heads a minimum thickness.
Dish thickness is out of scope: required Tdn ≤ 0.2 D
This code determines for heads a maximum 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 dish thickness.
Wall thickness is insufficient to bear the applied loads. Increase the wall thickness.