Oleodinamica Marchesini V0438/PP180 VAU 1/4 cross-line relief valve - prepared for sealing cap

Oleodinamica Marchesini V0438/PP180 is a VAU 1/4 cross-line relief valve with 1/4" BSP connections, a 10–180 bar spring setting range and provision for a sealing cap. Its manufacturer base designation is V0438. The full order code is listed by the supplier; the manufacturer sheet confirms the base valve, spring range and control option.

The applicable factory base has a maximum operating pressure of 350 bar and a maximum flow of 30 l/min. The 180 in the offered code identifies the upper spring-range value in that supplier offer; it is not a confirmed 180 bar factory preset or the maximum component pressure. The original standard-setting reference for this range is 90 bar. Confirm the actual delivered setting separately.

Two cross-connected relief branches limit shock pressure in the two lines of an actuator or hydraulic motor. Follow the repeated V1/V2 labels in the original diagram when connecting supply and actuator sides. The manufacturer recommends installation near the actuator to limit pressure loss and improve response. This circuit has no separate common tank port.

The /PP factory option means arranged for a sealing cap. It does not by itself establish that a cap, tamper seal or calibrated setting is supplied. The series photograph may show the standard screw execution. The base-table mass is provided only as a reference; an exact mass and external envelope for this preparation are not independently established.

The body is zinc-plated steel with hardened and ground internal parts and standard BUNA-N seals. Base body dimensions are labelled as reference body dimensions; no adjustment-dependent overall envelope is inferred. Pressure/flow curves use oil at 50 °C and 30 cSt, which are curve reference conditions rather than an operating-temperature range. The local PDF retains the complete relevant original spread, including its ordering notes and spring table.