Schuck has supplied 130 ball valves with a diameter of 42” for the Asia Gas Pipeline, which has a length of 1,818 km and extends from Uzbekistan to China. Over much of this distance the pipeline runs through regions with very poor or non-existent highway access. Despite the lack of a power supply and of telecommunications facilities in some places, the actuators for these valves have to provide the pipeline with a high degree of safety and reliability. A control centre has to be informed about any irregularities to enable the ball valves to be shut if necessary.
Almost all of these units are solar powered, to provide reliable communication and monitoring despite the unavailability of a mains electricity supply. This system met the client’s requirement for solar technology to supply sufficient power irrespective of the time of year and the weather conditions. The electricity supply has to be able to keep the actuators operating over a period of at least 20 days, even in absolute darkness, despite pollution, and even if the solar panels are covered over.
Schuck’s SEC 200 actuator was chosen for the main control system, providing maximum ease of operation and reliability. In this case too it offered unequalled functionality even where the installation space was very restricted. The SEC 200 ensures reliable communication with the control centre, monitors the solar technology (charging current, battery voltage,…) and compares the pressure in the pipeline with the previously assigned and approved parameters. The use of solar technology to power the actuator control system is only possible because of the very low current input of the SEC 200. The entire solar powered actuator system has been approved in accordance with the ATEX directive for use in environments where there is a risk of explosion, and its distinguishing features are its compact construction, simple operation and easy installation.
