Natural Gas Custody - Transfer, Measurement and Maintenance

Custody Transfer takes place any time fluids are passed from the possession of one party to another (e.g., from producer to pipeline, pipeline to plant, or pipeline to storage facility). Custody Transfer (or Fiscal Metering) refers to metering, that is a point of a commercial transaction, such as when a change in ownership of fluids takes place. Hence, Custody Transfer defines the point at which ownership changes hands for the product being measured.

The custody transfer system must generate detailed and indisputable cargo reports, based on accurate flow measurements and calculations. What makes custody transfer unique among flow-meter applications is that money changes hands and that accuracy requirements are higher than they are for most other applications. Hence, Custody transfer systems are more than just flow-meters and they represent a combination of highly engineered flow measurement systems for the intended application.

Custody transfer metering requires exceptional accuracy, repeatability, and auditable values. For instance, liquid custody transfer meters used to measure refined hydrocarbons have accuracy of ±0.125% or better, and repeatability in the range of ±0.02%.

 Objectives                             

• This course introduces participants to a variety of flow measurement technologies and systems that are used custody transfer applications, and gain an understanding about how measurement systems can work properly and accurately
• These include differential pressure (DP) measurement, turbine meters, positive displacement meters, Coriolis flow measurement, Magnetic and ultrasonic flow measurement
• Participants will gain the ability to determine if a metering system is adequate for the purpose, select appropriate systems and identify potential problems
• Other key learning objectives of this course include the understanding of the principles and applications of Multiple meters/meter runs, Flow computers, Quality systems, Calibration, Meter Runs, Proving and Supporting Automation
• Participants will also have a sound understanding of relevant fluid Laws that are needed for the use of flow measurement devices

Methodology

Lectures complemented by hands-on exercises using various schematic/blueprint drawings of various industrial layouts and Troubleshooting Software.

Target Participant

This course is open to all who have a science/engineering background, stakeholders in the oil and gas industry, field operators, supervisory engineers, process engineers, production engineers, control room personnel and any prospective oil and gas business investor.

Content

Day 1

• Basic Fluid and Gas Laws
• Pressure
• Flow Volume
• Continuity Principle
• Energy Law (Bernoulli’s Equation)
• Pressure Change Equation
• Flow Configurations (Flow Profiles)
• Laminar Flow
• Turbulent Flow
• Reynold’s Number
• Flow Losses (Friction Losses)
• Viscosity
• Ideal Gases
• Gas Laws, Boyle’s Law, Charles’s Law, Gay-Lussac’s Law

Day 2

• General Characteristics and Performance of Flow-Meters
• System Characteristics
• Flow range and viscosity range
• Performance
• Accuracy
• Stability and Repeatability
• Sensitivity
• Noise
• Linearity
• Reliability
• Applications and Usage
• Sizing
• Calibration

Day 3

• Types and Applications of Flow-Meters
• Differential Pressure (DP) Flow Meters
• Types; Orifice plates, Venturi tubes, flow nozzles, averaging Pitot tubes
• Systems
• Operating Principle
• Performance
• Properties
• Characteristics
• Uses and Applications
• Installation
• Calibration
• Standard AGA3
• Positive Displacement (PD) Flow Meters
• Types; Rotor, Oscillating Piston, Oval Gear, Rotating Paddle Slippage,
• Volume displacement Systems,
• Operating Principle,
• Performance,
• Properties,
• Characteristics,
• Uses and Applications,
• Installation,
• Calibration
• Turbine Flow Meters
• Types; Conventional and Helical
• Problems with Erosion, corrosion, Cavitation and Obstructions
• Systems, Operating Principle, Performance, Properties, Characteristics, Uses and Applications, Installation, Calibration
• Standard AGA7

Day 4

• Types and Applications of Flow-Meters
• Ultrasonic Flow Meters
• Systems, Operating Principle, Performance, Properties, Characteristics, Uses and Applications, Installation, Calibration
• Straight run requirement
• Standard AGA 9
• Magnetic Flow Meters
• Systems, Operating Principle, Performance, Properties, Characteristics, Uses and Applications, Installation, Calibration
• Coriolis Flow Meters
• Systems, Operating Principle, Performance, Properties, Characteristics, Uses and Applications, Installation, Calibration
• Standard AGA 11

Day 5

• Flow Measurement systems and other considerations
• Meter Factor
• Meter Runs
• Proving Systems; Direct, Indirect, Master Meter, Volume, Displacement
• Time Delay
• Quality Systems (Gas Chromatographs and Sampling Systems)
• Custody Transfer Skids
• Flow Computers and Communication
• Temperature and Pressure Measurements