Walvoil has developed a new directional valve speciﬁcally designed for mini and midi hydraulic excavators. The new DPX-HS valve targets machines from 1 to 9 tonnes.
Walvoil said that excavators in that range are typically controlled with load-sensing valves — a solution that better controls the machine and is liked by nonprofessional operators and rental ﬂeets — or open center valves with three ﬁxed pumps, a solution offering more performance in driving sensibility and faster control but requiring higher operator skills. The DPX-HS is designed to combines both technologies in two segments, separated by an intermediate section that works as a compensator.
The valve system works with one variable and one ﬁxed displacement pump, which the company said provides a compact and cost-efﬁcient solution.
The DPX-HS valve is available in three sizes: the DPX050 with a nominal ﬂow rating of 50 L/min (13.2 gpm); the DPX100 at 120 L/min (31.7 gpm); and the DPX160 at 160 L/min (42.2 gpm). All three sizes reach a maximum pressure of 300 bar (4351 psi) at the inlet port, the company said.