Electro-Hydraulic
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A4 US A4 US Electro-hydraulic The RFS range of electro-hydraulic valve actuators are of a robust, yet compact, modular design built to achieve the highest degree of reliability. Special consideration was given in the design process to facilitate installation and integration into customer control and communication systems. They utilise a scotch yoke mechanism which is field proven the world over in all types of fluid power applications. Our control system, like our actuators, is also of a modular design. Common control functions (i.e. remote/local, open and close) are provided as standard. The modular system facilitates integration of optional requirements such as automatic line break, high or low pressure close and differential pressure systems. Field modifications are practical and relatively easy to accomplish. This standardised product approach offers a higher standard of performance and a lower cost of ownership than a central hydraulic power unit solution. Electro-hydraulic Digital communication via Rotork Pakscan or other common valve actuators industry systems is an available option. Pakscan is the most secure of all bus highway systems. Unlike other systems, Pakscan can achieve long distance transmission without the need for repeaters. The two-wire system can communicate Design Features with up to 240 devices over a loop up to 20 km long. It is truly • Scotch yoke actuator in either double-acting or redundant, able to withstand a short circuit, open circuit or spring-return configurations. ground fault and continue to communicate with all devices in the loop. It will also provide the location and nature of • Closed hydraulic muliti-function system. the fault. (Reservoir sized per number of strokes required.) Partial stroke systems, to test operation of the valve/actuator • Operating pressure: Up to 350 bar with minimal impact upon the application, are another • Torque output: Up to 350,000 Nm available option. • Temperature range Mechanical: Standard -30 to 80 °C Optional -60 to 180 °C Electrical: Standard -20 to 40 °C Optional -60 to 60 °C • Area classification: Standard EX IIcb 2G EEx edm IIB T3, T4 (DIN EN 60079) Zones 1, 2 (ATEX 94/9/EG) Redefining Flow Control US A4 A4 US US A4 A4 US The Control System The modular design of the RFS control system facilitates internal electrical wiring. The door of the control cabinet has assembly, operation and maintenance of both standard and a pneumatic damper to withstand closure by wind during custom control logic solutions. Components are easily added, operation or maintenance, lockable handles and the facility replaced or removed. for pad-locking upon request. When the control enclosure in installed directly on the actuator, limit switches are located Valve actuation is performed in one of four ways: remotely within the enclosure. via energisation or de-energisation of the solenoid valves; automatically by control system logic (e.g., low, high or When the control is remotely mounted, a separate terminal differential pressure detection); locally via either an electrical box can be provided on the actuator. Five metres of cabling push-button station or the manual overrides incorporated into is normally provided for the interconnections, longer lengths solenoid valves or; by the manual hand pump. The speed of upon request. operation is independently adjustable for both the opening and closing strokes. Control enclosure: The pump/motor/accumulator provide the hydraulic supply 1. Local OPEN/CLOSE to the solenoid valves. The hydraulic pressure is regulated 2. Motor/Pump automatically by pressure switch. The motor runs as required and stops when reaching the preset maximum pressure. A 3. Selector REMOTE/LOCAL/OFF pressure limitation valve is integrated for safety. 4. Stainless Steel Cabinet A hydraulic accumulator system ensures operation in the 5. Terminal Box event of primary energy failure and also facilitates fast 6. Oil Level Indicator/Switch operating times. Operating times are infinitely adjustable in both directions. A torque control system, to protect the valve 7. Flow Controls (Stroke Speed) and actuator from overloading, is included as part of all our 8. OPEN/CLOSE Solenoid Valves standard control configurations. 9. Limit Switches All control components are contained within a weatherproof 10. Pneumatic Damper stainless steel cabinet. They are shipped assembled and tested complete with stainless steel tube and fittings and all necessary 11. Manual Hand Pump 1 2 3 4 5 6 7 8 9 10 11 Typical Gas-hydraulic Control Cabinet Redefining Flow Control US A4 US A4 A4 US A4 US Electro-hydraulic valve actuators Control Configuration RFS has extensive experience providing control systems to meet the operational and safety needs of our customers. We have developed a variety of standard control packages that meet the majority of typical specifications. We can also provide customised control solutions to meet the demands of any actuation application. The range of solutions include double-acting and spring-return options for On/Off, ESD (emergency shut-down) requirements. Our standard control packages are outlined below: Type Function Description Two solenoid valves (SOV’s) normally de-energised. Actuator will open (or move to intermediate position) upon energisation of OPEN SOV. Electric Remote EH Actuator will close (or move to intermediate position) upon energisation of CLOSE SOV. Fail in Place Actuator will remain in place upon loss of signal to SOV’s. Actuation still possible via accumulator charge or hand pump Electric Remote Same functionality as type EH. EHDH has in addition to the standard hydraulic system, EHDH Fail in Place a separate and dedicated system for the hand pump. Two solenoid valves (SOV’s), normally energised. Electric Failsafe Actuator will open upon energisation of both SOV’s. EHFSC Fail Close Actuator will close upon de-energisation of both SOV’s. At end of stroke, actuator cylinder is pressurised. DOUBLE-ACTING ACTUATORS Two solenoid valves (SOV’s), normally energised. Electric Failsafe Actuator will close upon energisation of both SOV’s. EHFSO Fail Open Actuator will open upon de-energisation of both SOV’s. At end of stroke, actuator cylinder is pressurised. One solenoid valve (SOV), normally energised. With latch upon request. Spring Failsafe Actuator will open upon energisation of SOV. EHSRC Fail Close Actuator will close upon de-energisation of SOV. Actuation still possible via accumulator charge or hand pump. One solenoid valve (SOV), normally energised. With latch upon request. Spring Failsafe Actuator will close upon energisation of SOV. EHSRO Fail Open Actuator will open upon de-energisation of SOV. SPRING- RETURN ACTUATORS Actuation still possible via accumulator charge or hand pump. US A4 A4 US US A4 A4 US Electro-hydraulic valve actuators Typical Schematic TORQUE LIMITING SYSTEM The quantity of cylinders is determined by actuator size TLS ITEMDESCRIPTION S1 Local OPEN Switch S2 Local CLOSE Switch EExdIIC T6 S4 Selector LOCAL/REMOTE/OFF OPEN S10 Limit Switch OPEN OPTIONAL CLOSE S4 S11 Limit Switch CLOSE S2 ELECTRICAL OR S10 S11 MECHANICAL S14 Max Pressure Switch S1 SAFETY SYSTEM POSITION S15 Min Pressure Switch OPTIONAL LINEBREAK INDICATOR B3 Level Switch BUS SYSTEM HIGH PILOT Y1 Solenoid OPEN EExdIIBT4 LOW PILOT Y2 Solenoid CLOSE EMERGENCY OFF Y2 Y1 EEx d/meIIT4 BLADDER ACCUMULATOR The quantity and dimensions CLOSE OPEN are determined by application specific requirements B3 T T T3 IC a / d I P P EEx i M S14 S15 EExdIIC T6 EEx e/d IIT3 Scan with your smart phone for more information on this product range Corporate Headquarters A full listing of our worldwide Rotork plc Electric Actuators and Control Systems sales and service network is tel +44 (0)1225 733200 fax +44 (0)1225 333467 Fluid Power Actuators and Control Systems available on our website. email [email protected] Gearboxes and Gear Operators Precision Control Instruments www.rotork.com Projects, Services and Retrofit Formerly F703E. All Rotork Fluid Systems actuators are manufactured under a third party accredited ISO9001 quality assurance programme. As we are continually developing our PUB021-006-00 products, their design is subject to change without notice. The name Rotork is a registered trademark. Rotork recognises all registered trademarks. Issue 11/12 Published and produced in the UK by Rotork Fluid Systems. POWTG1112 US A4 US A4.