LNG Custody Transfer and Metering
Explore how LNG quantity and quality are measured for custody transfer, including tank gauging, temperature, composition and energy calculations.
System context
Cargo measurement
Technical topic pages show the knowledge scope behind LNG University learning. Course, assessment and credential availability depends on the applicable program.
Relevant roles
Marine operators · Commercial professionals · Measurement engineers · Terminal operators
Prerequisites
LNG fundamentals
Knowledge level
Intermediate technical coverage with system and operational context.
Learning outcomes
What this topic is intended to help you understand
- Identify the main measurements used in LNG custody transfer.
- Explain why temperature, tank tables and composition influence calculated quantity and energy.
- Recognize the need for controlled measurement procedures and calibration.
Technical scope
Equipment, concepts and terminology
- Tank gauging
- Temperature measurement
- Tank calibration tables
- Gas chromatography
- Density calculation
- Gross and net energy
- Vapor measurement
- Measurement uncertainty
Operating context
How the topic connects to plant operation
- Pre-transfer measurement checks
- Data validation
- Reconciling ship and shore measurements
- Recognizing measurement anomalies
Safeguards and controls
Protection and risk-control context
- Calibration control
- Instrument traceability
- Independent verification where required
- Controlled calculation methods
Technical learning does not replace site procedures, OEM documentation, engineering calculations, permits, supervision or facility-specific authorization.
Engineering documents
Documents commonly connected to this subject
- Custody-transfer procedure
- Calibration certificates
- Tank tables
- Measurement reports