For tank root valves on product oil storage tanks (tank farm emergency shutdown valves). The medium is light oil such as gasoline and diesel at ambient temperature in atmospheric tanks, with a typical pipeline design pressure of 1.6 MPa. The medium is a flammable, explosive liquid hydrocarbon and the tank farm is a hazardous area.
Tank root inlet and outlet piping is equipped with tank root valves, emergency shutdown valves, metal hoses and process operation valves. Tank root valves must respond quickly and provide ESD emergency shutdown, including fail-safe action on power loss; they must remain free from sticking after long periods fully open and must be able to trigger emergency shutdown in a fire.
Application Focus
1. Fast response and ESD: rapid action under fault conditions; with no power supply, the actuator can still stroke the valve through 1–2 full travel cycles.
2. Long periods fully open and sticking risk: depot upgrades often convert the valve closest to the tank into an emergency shutdown valve. Because it stays fully open for long periods, it must still close rapidly in an emergency without seizing.
3. Fire detection and emergency action: the emergency shutdown valve is the most important safety barrier in a tank farm; it must detect a fire in good time and execute the preset action.
Solution Overview
1. Two series, CR (quarter-turn) and CL (linear), match the ball valves, high-performance butterfly valves and gate valves commonly used for tank farm emergency shutdown service, giving broad compatibility.
(1)Fast stroking: configurable hydraulic power modules deliver fast, interlocked control; with an accumulator module, emergency shutdown can be completed in as little as 1 s.
(2)High-performance modulation: servo variable-frequency control with a fully sealed hydraulic drive gives fast response (3 Hz), high accuracy (0.2%) and a high duty cycle (1,800 cycles/h), with long maintenance-free intervals.
(3)Fail-safe on power loss: an optional electromagnetic accumulator module drives the valve to its safe position (fail-last FL / fail-close FC / fail-open FO).
2. Partial Stroke Test (PST): Chuanyi electro-hydraulic actuators perform a small-angle partial stroke and return without disturbing the process (interval and stroke angle are configurable), eliminating the risk of seizure after long periods without movement and enabling periodic proof testing.
3. Fire relief valve (integral fusible plug): uses an inherently safe fusible-alloy thermal element instead of a conventional glass bulb, with a melting point selectable between 60 °C and 250 °C to suit site safety rules.
Customer Value
1. Supports major hazard source control, builds a multi-layer incident isolation mechanism and lowers safety, compliance and reputational risk.
2. On-line PST proof testing confirms the condition of safety equipment without a shutdown, increasing the real value of the safety investment.
3. Suited to both new depots and upgrades of existing sites: no instrument air required, compatibility with multiple valve types, and fit for digital and safety upgrades.
4. Balances tank farm safety with continuous operation and optimises asset lifecycle management.
Related Products:
CL electro-hydraulic actuators
CR Series electro-hydraulic actuators
