ELECTROHYDRAULICS IS THE most widespread motion control technology in typical applications for oil & gas such as: top drives; skidding and chain jack hydraulic systems for offshore drilling platforms (2); hydraulic stabbing arms for drillstring mating, etc.
These applications demand advanced automation, high performances, steady reliability, operational cost reductions and, in addition, they have to provide high level of safety to the employees as well as the suitable certifications to operate in potential explosive environments.
The fluid power driving these servo-systems is supplied by tailor-made hydraulic power units designed and manufactured according to the international safety norms for applications in any classified potential hazardous areas.
Thanks to its long know-how in the oil & gas market, Scoda have been able to develop modern hydraulic power units equipped with insulated cabinet and zero leakage connections; they are also protected from aggressive environmental substances by specific painting treatments widely used and qualified into naval and offshore markets.
The ex-proof solenoid valves and proportionals as well as auxiliary electromechanic components are supplied with ATEX, UL, IECEx or ROSTECHNADZOR certifications; in addition the on-off solenoid valves are certified by TÜV and SIL3 (Safety Integrated Level) thus granting highest safety level in terms of probability of dangerous failures that could occur in hazardous area.
These hydraulic systems are fit with casing, cabinet and reservoir in stainless steel mainly and they can also run with HFA fluids or with pure water thanks to the new Atos range of stainless steel valves suitable for operating in demanding working conditions and in ambient temperature down to -40°C, that is considered extreme borderline of hydraulic applications. Power units and systems are supplied with technical handbook and the relevant CE and ex-proof certifications i.e. with all the documents needed by the operator to speed up the commissioning procedures.
A prominent example of successful modern electrohydraulic application is the top drives drilling operation in the oil derrick. They are equipped with stabbing arms that automatically mate the drill string chain. This advanced system does not require the presence of workers to perform duties while on platform; therefore the accident at work, the unscheduled production costs and the downtime over the rig operations are significantly reduced.
These advanced running automations are performed thanks to the new Atos’ servoproportionals equipped with ATEX ex-proof on board electronics, able to carry out better motion control and high dynamic closed loop of position and force. The integration of digital electronics to the ex-proof valves allows to manage standing alone closed loop controls and to limit the remote communication with the central control unit for command signals and diagnostic only, through CAN-Bus or PROFIBUS interfaces.