Taplow and Marsh Lane Control Structures, Hydraulic-fluid Power Pack

Tender description

The Works to be procured are (A) onsite service of the existing fixed hydraulic-fluid power pack (HPP) and (B) the design, assembly, fabrication, testing & commissioning (off- and on-site), delivery and training of a road legal towable, self-powered HPP unit. The Sites are Taplow and Marsh Lane control structures situated on the Jubilee River in Maidenhead, south east England. Hydraulic-fluid Power Packs (HPP) are utilised on several Environment Agency (“EA”) flood defence / flow control gate assets for operational condition and repair and maintenance work as well as abnormal circumstances. Gate assets in this User Requirement Technical Specification for the tender package of work utilising HPP are typically radial gates and tilting weirs. EA HPP utilised on flood defence assets typically consist of: oil tank/reservoir, for storing the oil used in the system and its top structure which is used for mounting the control devices; hydraulic cylinder, for actuated movement of radial gates and tilting weirs; oil filters (suction and inline) and air dehumidifier, for the removal of heavy particulates and air removal respectively; submerged displacement pump type and electric motor, with motor overload protection and automatic changeover where required; flow-directing valves, solenoid operated (typically two-way) and controlled by a pilot valve depending on function in hydraulic circuit; pressure-relief valve and flow-regulating valve, typically used for gate/weir lowering speed; pressure switches, preset to detect overpressure and pressure drop for de-energizing the electric motor(s) during operation; monitoring and conditioning components, such as gate/weir actuator limit switches, oil tank/reservoir heater and fluid level switch, hydraulic circuit oil pressure gauges; hydraulic cylinder hand pump, for manual operation of the hydraulic cylinder in the eventuality of power supply, electric motor and, pump failure; and, gauge & test points, for commissioning.