Oleodinamica Marchesini V0638/6 VU MM 1 1/2 male/male in-line check valve — 6 bar cracking pressure

Oleodinamica Marchesini V0638/6 is the VU MM 1 1/2 male/male in-line check valve with the explicitly printed 6 bar cracking-pressure spring and 1 1/2" BSP connections. The factory spring matrix and selected supplier offer identify this same complete article. Its size row gives 320 bar maximum operating pressure.

Flow is free from V to C when the forward differential pressure opens the guided poppet; reverse flow from C to V is blocked. The 6 bar cracking pressure is an opening reference, separate from the component pressure limit and pressure loss at flow.

The manufacturer size row specifies maximum flow 300 l/min.

The body is zinc-plated steel with hardened and ground internals. The factory describes guided-poppet sealing without leakage but does not identify a seal compound. Common-body dimensions are length L 86 mm and hexagon size 55 mm; the size table gives mass reference 0.910 kg without a separately weighed spring execution.

The local technical PDF retains the complete relevant original manufacturer spread, including the applicable size row, spring or option legend, hydraulic diagram and drawing. Neighbouring executions apply only to their identified rows. Any 50 °C oil temperature and 30 cSt viscosity beside curves are test conditions, not operating limits.