Compressor Station Piping – Pipe Diameter, Wall Thickness and Gas Velocity This application uses gas velocity and flow rates to determine the minimum required pipe diameter for station piping. 𝑣 − Gas Velocity[ft/min] 𝑄 − Flow Rate[MMCFD] 𝑊𝑡 − Wall Thickness[in] 𝑃 − Design Pressure[psi] 𝐹 − Design Factor 𝐸 − Longitudinal Joint Factor 𝑇 −Temperature Derating…
Reciprocating Compressor – Cylinder/Equivalent Capability & Horsepower This application uses a positive displacement compressor model to deliver gases at high pressures. With piston displacement reciprocating compressors, often final outlet temp could be a concern. Piston Displacement Single-Acting Piston Compression on the Outer End Only: Single-Acting Piston Compression on…
Centrifugal Compressor – Fan Laws This application uses the affinity laws to calculate the volume capacity, head when the speed of the impeller is changed. Understanding the ratio of specific heat for the gas being used in the compressor may present challenges. Gas volume flow is proportional to the impeller…
Centrifugal Compressor – Required Polytrophic Horsepower This application uses initial impeller speed and final impeller rotational speed to determine final flow rate, compression head and final shaft Horsepower (HP). One drawback is the difficulty to determine efficiency which is based on the ratio of specific heat for the gas being…
Centrifugal Compressor – Required Adiabatic Horsepower This application uses a compression unit that calculates a natural gas-fired turbine to turn a centrifugal compressor. The centrifugal compressor is like a large fan inside a case, which pumps the gas as the fan turns. Size of the fan and speed within the…
Centrifugal Compressor – Adiabatic Head Using the centrifugal compressor application resets when the head is developed by increasing gas velocity to create kinetic energy. As compression ratio drops, adiabatic efficiency drops. One limitation of the calculation is that it does not consider the heat gained or lost. 𝐻𝑎 − Adiabatic Head[ft…
PLTB Gas and Liquid Services for Horizontal Direction Drilling Lite with Plastic Pipes Introduction The Pipeline Toolbox is home to many tools and calculators. The PLTB User’s Guide presents information, guidelines and procedures for use during design, construction, operations and integrity tasks for field or office applications.Horizontal directional drilling (HDD)…
DCVG – %IR Drop DCVG surveys are typically performed on coated pipelines with a view to determining the location of holidays (coating defects) or other defects, such surveys can be used to not only pinpoint the location of defects, but they can also be used to provide a measure of…
Required Number of Anodes and Total Current Requirement These calculations are the basis for cathodically protecting underground piping structures. Spacing requirements of anodes can drive up the costs of the cathodic protection impressed current systems. The anode current output is calculated using Ohm’s Law, 𝐼𝑎 — Anode current output(Amps)𝐸 — Driving…
Contents Rudenberg’s Formula for the Placement of an Anode Ground Bed This formula considers the attenuation of the pipe to determines the required structure voltage based on the current output. Rudenberg’s formula is very theoretical just using pipe parameters. Other factors to be considered include the presence of foreign metallic…