Oleodinamica Marchesini V0391/RP18 single counterbalance valve for closed-centre circuits

Oleodinamica Marchesini V0391/RP18 is the 3/8-inch BSP single VBCD type A counterbalance-valve execution for closed-centre hydraulic circuits. The complete article is explicitly listed on the current manufacturer series page and as an actual Hikom catalogue item. Hikom explicitly states pilot ratio 1:8 for this exact full order code.

The family controls actuator movement and retains an overrunning load in one direction. Its closed-centre design is described by the manufacturer as insensitive to back pressure. Connect V1 and V2 to the supply and C1 to the free-flow actuator side and C2 to the load-holding side, following the family circuit. The mounting is in-line.

The shared family construction uses a zinc-plated steel body, hardened and ground steel internals and standard BUNA-N seals. The representative manufacturer family photograph identifies the family; it does not certify the geometry or internal pilot construction of this exact RP18 execution.

The linked original manufacturer sheet documents the base family and prints 1:4.5 base rows. Those rows do not establish the pressure rating, maximum flow, calibration, mass or dimensions of this 1:8 article. These variant-specific values remain unassigned. The supplied pilot ratio is identified as supplier-stated and is not replaced by the base-table ratio.

The local PDF retains the complete original family reference with a clear applicability note. It supplies the family operating principle and material reference, and is not an RP18-specific dimensional drawing, rating certificate or confirmation of a delivered pressure setting.