SAUER DANFOSS roller M44 hydraulic pump
The test and repair process of the M44 and M46 main pumps from Sauer-Danfoss is conducted with precise engineering and numerical evaluation. Initially, the pump is removed from the hydraulic system, and a **preliminary inspection for leakage and pressure** is performed. System pressures are measured numerically using a digital pressure gauge for example, the standard inlet pressure is 6–8 bar, while the operating outlet pressure is checked up to 350 bar for the M44 and 400 bar for the M46. Pump flow at 1,500 RPM is measured between 150–165 liters per minute. The **input shaft torque** is evaluated with a torque meter up to 450–500 Nm to ensure proper power transmission.
In the second stage, internal components including the cylinder block, pistons, and swash plate are inspected with precision tools such as digital micrometers and wear gauges. The **maximum allowable deviation for piston diameter and cylinder bore is 0.02 mm**, and any component beyond this tolerance is replaced. O-rings and seals are replaced according to operating pressures of 350–400 bar and flow rates of 150–165 L/min. The drive shaft is tested for torque resistance and wear to ensure stable operation and prevent abnormal vibrations.
The final stage involves pump assembly and **numerical perfor
