Why Does a Hydraulic Breaker Stop Striking? Causes and Solutions from a Professional Manufacturer

Hydraulic breakers are powerful attachments that convert hydraulic energy into mechanical impact energy, making them essential tools for breaking rocks, concrete, and other hard materials efficiently. With simple structures, fewer failures, lower maintenance costs, and high impact force, hydraulic breakers can significantly improve productivity when used correctly.

However, like any mechanical equipment, hydraulic breakers may encounter operational issues over time. One of the most common problems is intermittent or paused striking (piston stop) during operation.

Why Does a Hydraulic Breaker Stop Striking? Causes and Solutions from a Professional Manufacturer

So, what causes the hydraulic breaker piston to stop striking?

During the breaker’s working cycle, the piston is driven by the adiabatic expansion of nitrogen gas in the accumulator chamber, moving in a quasi-uniform acceleration motion. As the piston reaches the mid-section and passes the control port, the main valve’s V2 chamber connects with the return channel, causing the V2 chamber pressure to drop. In response, the valve spool, under the high-pressure oil in the V4 chamber, begins to shift downward — initiating the impact stroke.

After the impact is delivered, the piston momentarily pauses when the valve reaches its lowest position — this is a normal part of the cycle. The piston then rebounds and starts a new cycle.

However, irregular or prolonged piston pauses may indicate issues such as:

• Low nitrogen gas pressure in the accumulator
• Valve spool wear or sticking
• Hydraulic oil contamination
• Improper flow or pressure from the excavator
• Internal component wear or misalignment

As a professional hydraulic breaker manufacturer in China with 25 years of experience, Zhengzhou Hanyun specializes in OEM production of SB Series (Soosan type) and HB Series (Furukawa type) breakers. Our chief engineer from Yantai Eddie Precision Machinery and our advanced production equipment—including Aichelin heat treatment furnaces, Doosan machining centers, and -190°C cryogenic systems—ensure consistent quality and performance.

Understanding the root cause of striking interruptions can help extend your breaker’s lifespan and avoid unnecessary downtime. For high-performance hydraulic breakers and technical support, contact us today!