Moog's Digital Interface Valve (DIV) is an advanced hydraulic valve with microprocessor-based electronics and a choice of fieldbus interfaces. This type of valve offers configurable functions that enable customers to define the dynamic behaviour of the valve and adapt its characteristics to particular application requirements, while providing high-precision digital control of both pressure and flow.
The DIV also benefits from standard functions such as diagnostic capabilities, integrated monitoring of key environmental and internal characteristics, valve parameter modification, and remote or on-site access, making this one of the most innovative hydraulic valves on the market.
Moog says that the DIV's ability to download parameters via the fieldbus connection or directly from the PLC program enables valve parameters to be optimised during machine operation - and even mid-cycle.
Furthermore, the DIV is designed to withstand the difficult temperature and vibration requirements of demanding applications, being resistant to shock and vibration to 60g and 30g, respectively.
Decentralisation enables tasks to be assigned to local devices rather than the main control device, providing customers with increased flexibility and functionality. By conforming to the CANOpen, Profibus or EtherCAT protocols, the DIV has a clearly defined data-exchange mechanism, so compatibility between conforming devices is assured.
Future-proof
Another benefit of the DIV is lower installation costs due to a serial-wiring scheme, which reduces the amount of wiring and improves noise immunity. With industry moving towards open architectures to future-proof capital equipment investments, Moog says its developments lead the hydraulics sector with clearly defined data-exchange mechanisms and published device profiles.
To make the product easy for customers to use, Moog engineers developed a Windows-based graphical user interface for changing the valve's parameters or characteristics without the need for detailed knowledge of fieldbus. Also used for performing detailed diagnostics and fault-finding, this software provides flexibility and convenience for commissioning and servicing, as well as simplified maintenance.
The DIV is available with a linear variable displacement transducer (LVDT) sensor integrated for velocity and position control of the valve spool, as well as the option of an integrated sensor for pressure control.
Nick Delport, a Moog application engineer, states: "Distributed servo control through a fieldbus interface is the future of motion control and the DIV's embedded digital microprocessor is the foundation for enhanced functionality and flexibility. The digital interface valve is a platform on which future generations of high-performance servo valve control will be based."
Applications for this type of product include the pitch control on wind turbines, providing benefits such as: reduced wiring; stable signal transport via fieldbus; diagnostics of rotating components; and exchange of valves without new adjustments. The DIV is also at home in paper mills (plungers, pressure control and paper cut movements) and in heavy industry - such as for optimising machine performance by co-ordinating axes and changing the dynamic parameters of the valves to optimise machine performance, without manually recalibrating the machine.
