In industries where liquid inventory management is critical—such as oil & gas, chemical processing, and bulk storage—accurate tank level measurement is non-negotiable. That’s where Servo Tank Gauges (STGs) come in. Renowned for their precision, reliability, and real-time performance, STGs play a vital role in modern tank gauging systems around the world.
STGs are widely adopted in industries that require custody transfer-grade measurement, such as:
Crude oil storage
Petrochemical tanks
Refined product terminals
LNG and LPG tanks
How Does a Servo Tank Gauge Work?
The servo tank gauging system operates based on mass balance and position control principles:
A displacer is suspended in the tank by a stainless steel wire.
The servo motor lowers or raises the displacer until it reaches the liquid surface (buoyancy point).
The motor continuously adjusts to keep the displacer balanced at the interface.
The system measures the exact position of the displacer and calculates the liquid level with high precision.
Many advanced STGs also measure:
Interface level (between oil and water)
Density (via movement through the liquid column)
Temperature (with integrated sensors)
✅ Key Benefits of Servo Tank Gauges
1. High Accuracy
Servo tank gauges offer millimeter-level precision, making them ideal for custody transfer applications where financial accuracy is critical.
2. Reliable Performance
With no moving parts inside the liquid, servo gauges are less prone to mechanical failure and can operate reliably in harsh environments.
3. Multi-Variable Measurement
STGs can simultaneously monitor level, interface, density, and temperature, giving a comprehensive picture of the tank contents.
4. Integration with Control Systems
Modern STGs support digital communication protocols (e.g., HART, Modbus, Foundation Fieldbus, or Tankbus), making them compatible with Distributed Control Systems (DCS) and inventory management software.
5. Safe for Hazardous Environments
Explosion-proof and intrinsically safe models are available for ATEX or IECEx certified environments, ensuring safe use in flammable or explosive atmospheres.
Applications of Servo Tank Gauges
Servo tank gauges are found in:
Tank farms and terminals
Refineries and petrochemical plants
Bulk liquid storage facilities
Marine loading/unloading systems
LNG and cryogenic storage tanks
Whether it’s crude oil, jet fuel, chemicals, or liquefied gases, STGs provide the confidence needed for accurate reporting, regulatory compliance, and inventory optimization.
Servo Tank Gauges have set the standard for precision liquid level measurement in critical industries. Their ability to deliver accurate, stable, and comprehensive readings makes them a smart investment for any operation that requires tight inventory control and secure product transfer.