Z2S Modular Check Valve: Preventing Load Drift
Load drift in hydraulic circuits often traces back to internal leakage through the directional valve. This article explains why a standard check valve may not hold position under load, and how the Z2S modular pilot-operated check valve addresses the problem by blocking one or both actuator ports. Key specifications and typical applications are outlined.
A hydraulic cylinder that slowly drops when the control lever is in neutral is a familiar complaint. The pump is off, the valve is centered, yet the load keeps moving. In most cases, the cause is internal leakage through the directional valve.
The problem: holding a load without drift
In circuits where an actuator must hold position for extended periods - a boom suspended above an access panel, a press platen waiting between cycles - even a small internal leak becomes visible. Over 20 or 30 minutes, a few drops per minute turn into millimeters of drift.
The standard check valve in a directional valve is not designed for zero-leakage holding. When the circuit requires the actuator to stay put without a mechanical lock, a more effective solution is needed.
The solution: modular pilot-operated check valve
The Z2S Modular Hydraulic Check Valve is a pilot-operated check valve in sandwich plate design. It mounts between the directional valve and the manifold, blocking one or both actuator ports without adding piping.
View Z2S Modular Hydraulic Check Valve Specifications
Key specifications:
Sizes: 6, 10, 16, 22
Maximum operating pressure: 315 bar
Porting pattern: ISO 4401, DIN 24340 form A
Cracking pressures: 1.5 / 3 / 6 bar options
Blocking options: channel A, channel B, or both
Seal material: NBR or FKM
Ambient temperature: -30°C to +80°C (NBR seals)
View Z2S Modular Hydraulic Check Valve Specifications
Where it fits
Modular check valves are commonly used in industrial presses, injection molding machines, metal forming equipment, and construction machinery. The sandwich plate design simplifies maintenance, since the valve can be removed without disturbing the rest of the stack.
About the supplier
Shijiazhuang Laiye Import & Export Trading Co., Ltd. is part of Hebei Onederful Hydraulic Technology Co., Ltd., founded in 1988. OEM customization is available with drawings and specifications.
