In-line pressure relief valve

Oleodinamica Marchesini V0688/300 VMP L D5 1/4 in-line pressure relief valve

Model: V0688/300 · Oleodinamica Marchesini
Maximum operating pressure (bar)350
Maximum flow (l/min)30
Valve functionPressure relief to tank
Port connection1/4" BSP
Body materialZinc-plated steel
MountingIn-line

Description

Oleodinamica Marchesini V0688/300 is the VMP L D5 1/4 in-line pressure relief valve with the actual supplier-selected 80–300 bar spring range and 1/4" BSP connections. The manufacturer prints the base row and finite spring table; the full calibrated code is selected on the supplier offer rather than generated. Its base component row specifies maximum flow 30 l/min and maximum operating pressure 350 bar.

Connect P to the pressure line and T to tank. The P connection is reversible. The relief element opens when pressure reaches the adjusted setting. The factory note identifies the additional nut on V0688.

The 80–300 bar range describes spring adjustment capability rather than a confirmed delivered preset. The catalogue standard-setting reference for this spring is 150 bar. The spring endpoint does not override the separately stated 350 bar component limit.

The body is zinc-plated steel with hardened and ground internals, standard BUNA-N seals and guided-poppet sealing with negligible leakage. The common size row gives a mass reference of 0.940 kg; no separately weighed calibrated spring execution is stated. Handknob and sealing-cap suffixes denote other adjustments and are not added to this screw-adjusted article.

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.

Full specifications

Technical specifications
Product type In-line pressure relief valve
Maximum operating pressure (bar) 350
Pressure setting maximum (bar) 300
Pressure setting minimum (bar) 80
Maximum flow (l/min) 30
Port thread standard BSP
Mounting In-line
Internal parts material Hardened and ground steel
Sealing type Guided poppet
Adjustment Screw
Factory type designation VMP L D5 1/4
Manufacturer Oleodinamica Marchesini
Manufacturer part number V0688/300
Product family VMP-L-D5
Standard setting reference (bar) 150
Base execution mass reference (kg) 0.94
Technical specifications
Port connection 1/4" BSP
Body material Zinc-plated steel
Valve function Pressure relief to tank
Technical specifications
Seal material BUNA N