Yale VSM Safety-Check Valves ? 700 Bar Hydraulic Load-Holding Valves

Description

The Yale VSM safety-check valve range is engineered to provide reliable load holding and pressure retention in high-pressure hydraulic systems operating up to 700 bar. These valves are an essential safety component wherever uncontrolled pressure loss must be avoided, such as during load holding, lifting, jacking or positioning operations.

Depending on their installation position within the hydraulic circuit, VSM valves perform different safety-critical functions. Whether installed directly on a hydraulic cylinder or combined with a directional valve, the VSM range ensures that pressurised cylinders remain securely locked in position, even in the event of hose failure or pressure fluctuations caused by valve operation.

Function and operating principle

All Yale VSM safety-check valves allow free oil flow towards the hydraulic cylinder, enabling smooth lifting or extension. Once pressure is applied, the integrated check valve automatically locks, preventing any unintended return flow and holding the load precisely in position.

When lowering or retracting the cylinder, the operator can finely control the descent speed by opening the throttle valve via the hand wheel. This ensures smooth, controlled pressure release without sudden drops or shock loading. A built-in safety pressure valve protects the cylinder from overloads caused by external forces acting on the load.

This controlled operation makes the VSM range particularly suitable for applications where operator safety, load stability and precision control are critical.

Model variants and selection guidance

The VSM series is available in two configurations, optimised for different installation requirements:

VSM-11 ? Hose-break safety valve
The VSM-11 is designed to be screwed directly into the oil port of a hydraulic cylinder. In this position, it functions as a hose-break fuse, immediately locking the cylinder if a hydraulic hose fails or pressure is suddenly lost. This makes it ideal for mobile lifting equipment, jacking systems and vertical load applications.

VSM-21 ? Load-holding valve for power packs
The VSM-21 is intended for use in combination with VHP directional valves. Installed between the pump and the cylinder, it ensures that pressure remains stable when operating the directional valve, preventing pressure drops and unwanted load movement during valve switching.

Typical applications
Load holding on hydraulic cylinders
Hose-break protection
Lifting and jacking systems
Hydraulic presses and positioning equipment
Power packs with directional control valves
Safety-critical hydraulic installations

Safety & user instructions
Always select the correct model based on installation position (VSM-11 or VSM-21).
Ensure correct orientation of oil ports during installation.
Do not exceed the maximum operating pressure of 700 bar.
Adjust the throttle valve gradually to control lowering speed safely.
Regularly inspect the valve for contamination or mechanical damage.