Page 7 - Industrial Technology EXTRA 24th May 2021

traditional solutions to make this design feasible for deliver configurable functionality to customers.
low-flow applications, perhaps by up to 40%. Flexibility on this level is not possible using
Optimum hysteresis and flow performance are standard mobile valves due to the use of castings,
prerequisites in mini and micro machinery, as is which require manufacturing in high volumes to be
flexible control. By bringing this type of valve to cost-effective. Moreover, changing the design is
market, it would be possible to achieve flows of up simply not practical, as it requires modifying or
to 30 l/min at the work port by using load-sense remanufacturing the mould, which can be costly
compensators on the inlet to the valve bank. and time-consuming.
Special logic elements would require Developing a valve with configurable
development to facilitate meter-out (post- functionality would also greatly reduce the need for
compensation) or meter-in (pre-compensation) remotely mounted ancillary valves, each of which
control. This capability would enable flow sharing or increases machine cost and complexity, as well as
prioritisation in the same valve bank, even at low weight and space demands.
flows, which would be unusual in the current Using the hydraulic integrated circuit principle -
marketplace. Post-compensation, in particular, is which focuses on energy-efficiency and the
excellent for increasing the efficiency and multi- reduction of weight and size - in a section-based
function capability of hydraulic systems in partial design would make a proportional solenoid
load or partial speed conditions. cartridge valve of this type extremely appealing.
It would also be beneficial if the assembly of There would certainly be no concerns regarding
these meter-in and meter-out sections could take configuration in line with specific customer
place in any order. In addition, perhaps sections requirements. Further flexibility would result from
with meter-in compensators could provide priority suitability for both open-centre and closed-centre
control to functions such as steering or systems. As a point of note, any such valve must
transmission. also provide flexible mounting and multiple inlet
It would also be beneficial if the assembly of section options to accommodate a range of pump
these meter-in and meter-out sections could take types.
place in any order. In addition, perhaps sections
with meter-in compensators could provide priority From concept to reality
control to functions such as steering or Today, this long-held vision for load sensing, priority
transmission. flow sharing valves has at last become reality. There
is now available a realistic and affordable way to
Configurable functionality move beyond traditional cast-iron mobile valves that
The use of manifold sections, particularly using a are simply too large and heavy for mini and micro
material such as aluminium drawn bar, would machinery.
further extend the valve’s flexibility by enabling the The newly developed Eaton SLV20 - which uses
small-batch production of individual sections that the company’s ESV9 four-way, three-position
add any bespoke functions the application requires, proportional solenoid cartridge valve - offers high
such as pilot-operated check valves, counterbalance flexibility and control, as well as significant space
valves or other remote functions. and weight savings, making it an ideal match for a
Ultimately, such a valve would offer design myriad of low-flow applications.
engineers a base from which to be innovative and www.eaton.com/new-sicv

May 2021 • INDUSTRIAL TECHNOLOGY EXTRA • p7