Pipeline contract includes ‘point of control’ security for Rotork valve actuators
Rotork IQPro intelligent electric valve actuators with Pakscan two-wire digital control networks have been ordered for a strategic new pipeline project in the United Arab Emirates. The Abu Dhabi Crude Oil Pipeline (ADCOP) will provide a vital export alternative to the Hormuz Strait “bottle neck” for the Habsham Oilfield, which is the collection centre for the bulk of Abu Dhabi’s onshore oil production activity.
Rotork’s success in the award of this contract has been assisted by the ability of the IQ actuation and Pakscan control package to meet customised demands for increased operational security. Modifications have been incorporated to enable the control system to identify and eliminate any potential on-site interference and unauthorised valve operations.
To achieve this requirement, the status of the ‘local/remote/stop’ operating switch on every actuator on a Pakscan loop is indicated at the master station controlling that loop, where it is also accessible by the supervisory controller. The digital state of this signal changes when the switch is moved to the ‘local’ or ‘stop’ positions, but the actuator cannot be operated locally and remains in remote control, where it can be operated over the network. At this point the supervisory controller can decide whether or not the local control request is authorised and, if it is, put the actuator into the control status required. In this way, the risk of unauthorised on-site operation is permanently eliminated, providing increased security and protection for the pipeline network.
Rotork has received orders for several hundred IQPro actuators on the project, controlled by five ‘hot-standby’ Pakscan master station loops. The actuator-dedicated Pakscan digital control system is particularly well suited to pipeline applications, since up to 240 field units can be supported by a single master station, controlling a two-wire network with a maximum length of 20 kilometres, without repeaters. Pakscan’s redundant field communication path technology provides complete cable fault protection and immediate identification of any break in the network loop. Such an event causes no interruption to the operation of the field units on the network.
Rotork’s client on the project is the Abu Dhabi Onshore Company (ADCO) and the China Petroleum Engineering & Production Company (CPECC) is the engineering contractor. The completed ADCOP project will include a 370 kilometre, 48 inch pipeline, capable of transporting 1.5 million barrels of crude oil per day to Fujairah on the UAE’s eastern coast, where a tank farm and export facilities are also being constructed.