Pressure Peaks in Hydraulic Systems: Risks for Sensors and Equipment

How do pressure peaks occur in hydraulic systems?

Pressure peaks result from abrupt changes in flow volume — for example, when valves are suddenly closed or pumps are rapidly stopped. This creates a pressure wave that moves at high speed through the medium. In closed systems, these waves can reflect and lead to short-term pressure surges well above the operating pressure.

Typical triggers of pressure peaks:

• Rapid closure of solenoid or ball valves
• Sudden change in pump rotation direction
• Air or gas inclusions in the system
• Cavitation (collapse of vapor bubbles)

What are the consequences of pressure peaks for sensors?

Pressure sensors are usually designed for a specific operating pressure and defined overpressure limits. Short-term exceedances — so-called "pressure spikes" — can lead to two scenarios:

Complete failure due to mechanical destruction

If the maximum pressure load is exceeded, the sensor membrane can rupture or the internal measuring element be destroyed. The failure is immediately recognizable.

Gradual measurement errors due to permanent deformation

With lesser but repeated overloads, the membrane deforms permanently. The sensor continues to function but provides inaccurate readings — which can lead to undetected miscontrol and quality issues.

How to avoid or mitigate pressure peaks?

Depending on the system design and application, various protective measures can be implemented to prevent pressure peaks or limit their effects.

Effective measures to reduce pressure spikes:

• Pulsation dampers: Dampen rapid pressure changes and prevent transmission to sensitive components.
• Pressure throttles: Reduce flow velocity at critical points and prevent abrupt pressure changes.
• Smooth-closing valves: Avoid sudden flow interruptions.
• Appropriate piping dimensions: Pipe diameter and lengths influence wave propagation.

Sensor-side protection strategies:

• Use sensors with higher overload safety
• Add protective membranes or mechanical preloads
• Place sensors outside particularly vulnerable areas

Conclusion: Protection starts with system understanding

Pressure peaks are common in hydraulic applications — but they are not inevitable. Through appropriate measures in system design and the targeted use of robust or protected sensors, damage can be effectively prevented. Especially in safety-critical or highly automated systems, proactive analysis and optimization of pressure conditions are worthwhile.

We are happy to assist you in selecting suitable sensor solutions for your application. Contact us — we will advise you competently and individually.