Subsidiaries

Historical Background
Thai Aviation Refuelling Co.,Ltd. (TARCO) was established on November 27, 1996 in order to operate hydrant pipeline network at Suvarnabhumi Airport. Currently, TARCO has registered and paid-up capital of 530 million baht. The Shareholder portfolio is Bangkok Aviation Fuel Services Public Co.,Ltd. (BAFS) owning 90% of the shares and Airports of Thailand PLC (AOT) having 10%. TARCO has started its constructions since April 12, 2001 and operated from September 28, 2006 in parallel with the official opening of Suvarnabhumi Airport.

Hydrant System Overview:
The aviation fuel service system at Sunvarnabhumi Airport begins with receiving aviation fuel from two transfer pipelines which are THAPPLINE from Thapp depot and JP-One line from Bangchack. The product is then quality tested and controlled at aviation fuel depot, BAFS. The fuel farm storage contains 4 tanks with approx. 60 million litres capacity feeding a hydrant system (24” twin feeder line) operating pressures from 9.5 – 12.5 bars. Jet A-1 fuel from the depot is then channeled through 8 hydrant pumps into the hydrant pipelines network which buried underground and spreading throughout the aircraft parking area and then to each of the 119 parking pits. The final step of the Jet A-1 fuel delivery from the hydrant pit to the aircrafts requires hydrant dispensers. These vehicles are provided with metering, filtration and control valves to safely control the flow of fuel into the aircraft, also equipped with pressure controls to regulate the suitable pressure into the aircraft.

TARCO’s hydrant pipeline system at Suvarnabhumi Airport comprises of 7 key components:

1. hydrant pipeline network
   Hydrant pipeline network is designed as a looped buried system circling the fueling apron, to transfer aviation fuel from the aviation fuel depot to all aircraft parking area. The piping design is in accordance with API 5L GrB, coating with Polyethylene and lining with Epoxy which consists of buried 24”, 16”, 12” and 6” inch NB.
   
   
2. Sectional Valve Chamber (SVC)
   The sectional valve chamber is used to isolate or segment portions of the hydrant system for an emergency maintenance and regular leak testing. The sectional valve chamber is equipped with Double Block & Bleed Valve with Motor Operate and pressure/temperature transmitter to examine the leakage of pipeline. In addition, the whole monitoring functions are controlled by computerized system called Supervisory Control and Data Acquisition System (SCADA).
   
   
3. Hydrant Pits Valve
   Hydrant pit valves function is to facilitate aircraft refueling at all parking stands by connecting between the underground hydrant system and dispenser, as well as to safely control the flow of fuel into the aircraft. The hydrant pits valves were installed underground apron and equipped with dual air pilot operate. Moreover, the pit is an environmental design such that it minimizes the ingress of ground water and also prevents the egress of spilt or leaking fuel.
   
   
4. Hydrant Control System
   Hydrant Control System is designed for monitoring sectional valves and read pressure, temperature of JET-A1 in the hydrant pipeline network. Data is then transferred to Tightness Monitoring System (TMS) for examination the leakage of pipeline with Leak Detection and Location. The hydrant control system also collects data from the Hydrant Emergency shutdown Push button (ESD) to open/close related valves to that vicinity.
   
   
5. The Hydrant Emergency shutdown system
   Hydrant Emergency Shutdown system (ESD) is an emergency shutdown buttons provided at every Aircraft stands with total 139 buttons. The system collects data from an ESD button and transfer via Fiber Optic Cable to SCADA. In case of emergency, when an ESD button is being pressed, the hydrant will be zoned and system shutdown is restricted to that vicinity.
   
   
6. Tightness Monitoring System (TMS)
   Tightness Monitoring System (TMS) is the statistical techniques that can examine the leakage of pipeline and define the leakage location by measuring pressure at various points along the pipeline. The system has demonstrable accuracy of 0.04 litres/hr/m3 and checks the leak location with the accuracy of ± 100 Meter
   
   
7. Cathodic Protection
   In order to protect the buried hydrant pipelines from corrosion, the cathodic protection system is applied. The buried pipelines are electrically separate from other metallic structures to protect the chemical action. additionally the impressed current (CP) system is used.