Oleodinamica Marchesini V0631/8 VU 1 1/4 in-line check valve — 8 bar cracking pressure

Oleodinamica Marchesini V0631/8 is the VU 1 1/4 in-line check valve with the factory-listed 8 bar cracking-pressure spring. The complete article code appears in the manufacturer spring matrix and on the selected supplier offer. Its common-body rating is 250 l/min maximum flow and 300 bar maximum operating pressure, with 1 1/4" BSP female connections.

Connect V to supply and C to the downstream circuit. Flow is free from V to C when the forward differential pressure opens the spring-loaded poppet; reverse flow from C to V is blocked. The 8 bar cracking pressure is the opening reference for this exact spring execution, separate from the component pressure limit and from pressure loss at rated flow.

The body is zinc-plated steel with hardened and ground internal parts. The manufacturer describes guided-poppet sealing without leakage. No seal compound or independent temperature range is stated on this sheet.

The common VU 1 1/4 drawing gives length L of 135 mm, hexagon size 55 mm and outside diameter 63 mm. Its table lists a base-execution mass reference of 1.646 kg; a separately measured mass for this spring option is not supplied. The standard-pressure alternatives in neighbouring columns do not replace the explicitly identified 8 bar execution.

The local technical PDF retains the complete relevant original manufacturer spread, including the exact spring-code matrix, cartridge row or stainless-code example. Neighbouring executions apply only to their identified rows. Any 50 °C oil temperature and 30 cSt viscosity beside curves are reference conditions rather than operating limits.