Product Overview
SF Double-Layer Tank (Steel - Fiber Reinforced Plastic) is the full name of a steel-reinforced glass fiber double-layer storage tank. It is a composite double-layer safety oil storage equipment with an inner steel and outer fiberglass structure. It is specially designed for high environmental protection and safety requirements scenarios such as gas stations, chemical industries, and oil product storage. It has core advantages such as anti-leakage, anti-corrosion, intelligent monitoring, and long service life. It is the mainstream environmentally friendly and compliant equipment to replace traditional single-layer tanks.
I. Product Structure 
• Inner layer (S - Steel inner tank)
It is made of high-quality carbon steel plates of Q235B/Q345R, with a wall thickness of 6–8mm (for the cylinder) and 8–10mm (for the head). It has high strength, good rigidity and is resistant to oil erosion. 
• Outer Layer (F - FRP Glass Fiber Reinforced Plastic Outer Sheath)
High-strength glass fiber reinforced plastic, with a thickness of ≥ 4mm, resistant to acids and alkalis, anti-electrochemical corrosion, water-proof, and anti-aging. 
• Intermediate interlayer (detection gap)
A 0.1–3.5mm through gap is maintained between the inner and outer layers, forming a leakage monitoring space. 
• Leak Monitoring System
Equipped with 24-hour online detectors (level/pressure/vacuum sensors), an audible and visual alarm will sound upon leakage, and remote monitoring is supported.
II. Core Technical Parameters 
• Material: Inner tank Q235B/Q345R; Outer tank FRP (fiberglass reinforced plastic) glass fiber reinforced plastic 
• Volume: 10 - 500 cubic meters (horizontal type is the main option, but vertical type can also be customized) 
• Design pressure: Atmospheric pressure / -2kPa to 3kPa (ground-level standard) 
• Design temperature: -40℃ to 60℃ 
• Interlayer gap: 0.1 - 3.5 mm 
• Outer tank thickness: ≥ 4mm 
• Service life: More than 30 years (about 10 years for single-layer tanks) 
• Monitoring accuracy: Leakage response ≤ 1 hour, Alarm sensitivity 0.1 L/h 
III. Core Product Advantages 
Safety leak prevention (double barrier + real-time monitoring) 
• Double-layer structure. In case of leakage from the inner tank, it will first enter the intermediate layer before directly contaminating the soil or groundwater. 
24-hour intelligent monitoring, immediate alarm in case of leakage, eliminating potential hazards and pollution accidents 
2. Exceptional anti-corrosion (double protection inside and outside) 
• The inner tank is resistant to oil and undergoes internal anti-corrosion treatment; the outer tank is made of FRP and is insulated without electrolytic corrosion. 
Resistant to groundwater, salt and alkali, weak acids and weak bases. Can be buried and requires no maintenance. 
3. Long-term Economic Benefits 
• The lifespan is 3 to 5 times that of a single-layer tank, and it can be safely used for 30 years. 
• No need for seepage prevention tanks, quick installation, short construction period, and extremely low maintenance costs in the long run. 
Compliant with environmental protection regulations, avoiding fines and treatment costs due to leakage. 
4. General Compliance 
Meet the requirements of the GB50156 standard for gas station design and the environmental protection and anti-seepage regulations. 
• Compatible with gasoline, diesel, kerosene, industrial oils, chemical solvents, etc. as neutral media 
IV. Applicable Scenarios 
• Underground oil storage at gas stations (standard feature) 
• Oil depots, chemical zones - Safe storage of flammable/combustible liquids 
• Airport, port, mine Temporary/Permanent Oil Product Storage Facilities 
Renovation of old stations (environmental protection upgrades, leakage risk management) 
V. Standard Configuration 
Manholes, feed ports, oil outlet ports, sewage discharge ports 
Level gauge port, thermometer port, safety valve interface 
Leakage detection system (sensor + controller + alarm) 
Outer tank anti-corrosion coating, grounding, lifting ears, reinforcing ribs 
VI. Usage and Maintenance 
• Directly buried installation, no need for a seepage prevention tank, solid and level foundation 
Use strictly in accordance with the design pressure, medium and volume. 
Regularly inspect the monitoring system, interface seals, and the integrity of the outer container. 
• Long lifespan, no need for regular anti-corrosion maintenance, and low long-term usage cost