Fault Phenomenon: Co-Nele KNL5600 safety functions normally when cold. During high-pressure testing (operating temperature), the safety valve malfunctions, the system unloads, and high-pressure operation is impossible.

Troubleshooting Process:
– Checked safety valve setting: set pressure correct.
– Checked valve seal: good sealing.
– Checked spring: spring not broken.
– Measured valve body temperature at operating temperature: found temperature too high.

Root Cause: The safety valve spring anneals due to heat, causing reduced spring force and premature opening.

Required Parts: Hydraulic safety valve assembly.