CALC : Flow : Bernoulli 071 : Submerged Pipe Wall Delta Pressure From Relative Elevation : Calculator

Description : Calculate the delta static pressure across the pipe wall of a submerged pipeline from the relative elevation.

Discussion : The internal and external pressure both vary with elevation. The external fluid gauge pressure is assumed to be zero at the fluid surface. If the internal fluid is lighter than the external fluid the maximum delta pressure will occur at the highest submerged point on the pipeline. Conversely, if the internal fluid is heavier than the external fluid the maximum delta pressure will occur at the lowest point on the pipeline.

Figures :

• Bernoulli Submerged Delta Pressure Across Pipe Wall

Input Variables :

• ρe = External Fluid Density
• ρi = Fluid Density
• P1 = Section 1 Fluid Gauge Pressure
• Z1 = Point 1 Elevation Above Datum
• Z2 = Point 2 Elevation Above Datum
• Zs = Fluid Surface Elevation Above Datum
• g = Standard Gravity Acceleration At Sea Level

Output Variables :

• ΔP = Pipe Wall Delta Pressure
• P2 = Section 2 Fluid Gauge Pressure
• Pe = External Fluid Gauge Pressure

Calculation :

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CALC : Pipe : Wall Thickness 011 : ASME B31.4 Pipeline Wall Thickness - Onshore and Offshore : Calculator

Description : Calculate the ASME B31.4 wall thickness from allowable hoop stress

Discussion : Use the standard hoop stress design factors for onshore and offshore liquid hydrocarbon pipelines, or enter a custom design factor. To use a custom design factor select custom in the zone type selct box, and enter a custom design factor. For standard zone types you do not need to enter a design factor. To plot the custom design factor you must select the custom zone type. The allowable stress is calculated from the specified minimum yield stress SMYS.

References :

• ANSI/ASME B31.4 : Pipeline Transportation Systems For Liquid Hydrocarbons And Other Liquids

Calculation Steps :

• Allowable hoop stress
• Minimum wall thickness
• Nominal wall thickness, ID and D over t ratio

Options :

• Zone type : onshore pipeline, offshore pipeline, platform and riser, and custom design factor

Input Variables :

• A = Pipe Total Corrosion Allowance
• D = Pipe Nominal Diameter
• E = ASME Longitudinal Weld Joint Factor
• F = Pipeline Hoop Stress Factor
• P = Pipeline Design Gauge Pressure
• Sy = Pipeline SMYS - Specified Minimum Yield Stress
• Z = Zone Type

Output Variables :

• ID = Pipe Nominal Inside Diameter
• S = Allowable Hoop Stress
• dot = Pipeline Diameter Over Wall Thickness Ratio
• t = Pipe Hoop Wall Thickness
• tn = Pipe Nominal Wall Thickness

Calculation :

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CALC : Pipe : Wall Thickness 013 : ASME B31.4 and ASME B31.8 Pipeline Hoop Stress Based On Hoop Wall Thickness : Calculator

Description : Calculate the pipe wall hoop stress from the minimum wall thickness for ASME B31.4 and B31.8.

Discussion : The hoop stress is calculated for the minimum wall thickness by subtracting the corrosion allowance from the nominal wall thickness.

References :

• ANSI/ASME B31.4 : Pipeline Transportation Systems For Liquid Hydrocarbons And Other Liquids
• ANSI/ASME B31.8 : Gas Transmission And Distribution Piping Systems

Input Variables :

• A = Pipe Total Corrosion Allowance
• D = Pipe Nominal Diameter
• P = Pipeline Design Gauge Pressure
• tn = Pipe Nominal Wall Thickness

Output Variables :

• S = Pipeline Hoop Stress
• t = Pipe Hoop Wall Thickness

Calculation :

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