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 knuckle, dish – Tkn, Tdn
Thickness ‘as is’, meaning it is the design thickness taking into account corrosion and tolerance.
Nominal Inside Knuckle Radius – ri1n
Nominal inside radius of the knuckle (small radius). Custom defined size for torispherical and estimated size for elliptical.
Nominal Inside Dish Radius – ri2n
Nominal inside radius of the dish (large radius). Custom defined size for torispherical and estimated size for elliptical.
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
Elliptical Cap
Elliptical Cap
Torispherical Cap
Torispherical 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 knuckle and dish – Sk, Sd
Stress in the component at which it is still allowed (without failure) to use the component
Allowable stress at 20 °C knuckle and dish – Skt, Sdt
Stress in the component at which it is still allowed (without failure) to use the component at testing condition
Outside height – he
Outside height between tangent line and top of dish.
Nominal Required Thickness knuckle and dish – Tkrn, Tdrn
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.
Knuckle 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.
Knuckle thickness is out of scope: required Tkn ≥ 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.
Knuckle thickness is out of scope: required Tkn ≤ 0.2 D
This code determines for heads a maximum thickness.
Knuckle radius is out of scope: required: 0.05 ≤ ri1/ri2 ≤ 1.0
This code determines a minimum and maximum radius.

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.
Insufficient knuckle thickness.
Wall thickness is insufficient to bear the applied loads. Increase the wall thickness.
Disk thickness is smaller than required knuckle thickness.
Wall thickness is insufficient to bear the applied loads. Increase the wall thickness.