| parsianrahbalandeh |
| Iran |
| 02155130771 |
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
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| parsianrahbalandeh | 02155130771 |
| hydraulicmarket |
| Iran |
| 021-55130771 |
The repair process of the Bobcat M44 Sauer Danfoss hydraulic travel pump requires precise diagnostic analysis, as the pump operates at pressures up to 350 bar and flow rates near 90 liters per minute. Mechanical wear of pistons, valve plates, or bearings can reduce volumetric efficiency by more than 15 percent, leading to significant loss of travel power. Early symptoms often include unusual vibration, high oil temperature exceeding 85°C, and reduced response time in forward or reverse drive cycles.
Common causes of hydraulic pump failure in the Bobcat M44 include oil contamination above ISO 18/16/13 levels, cavitation due to improper suction line sizing, and overheating caused by insufficient cooling. Even a 10 µm particle entering the pump chamber can damage the swash plate surface, reducing service life by over 30 percent. Preventive maintenance such as oil filtration checks, seal inspection, and pressure relief valve calibration is critical for extending operational hours.
Repair costs for a Bobcat M44 Sauer Danfoss travel pump vary from 1,200 to 2,500 depending on the extent of component replacement, labor, and testing procedures. A full rebuild may require up to 12 working hours, including disassembly, precision lapping of valve plates, piston shoe replacement, and
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| hydraulicmarket | 021-55130771 |
