Underground tanks - Horizontal cylindrical single and double-walled tanks for underground storage of flammable and non-flammable liquids. Made by using shell plates and dished ends made in carbon steel type S235JR complying with UNI EN 10025. The external shell is welded by submerged arc welding procedure while the internal part is MIG-welded. Parts are designed in compliance with rules and regulations in force.
Single-walled tanks form an impermeable containment; they act as the inner tank of double-walled tanks.