| parsianrahbalandeh |
| Iran |
| 02155130771 |
The main hydraulic pump A8VO55, manufactured by Rexroth, is an axial piston pump with a dual design, used in open-circuit hydrostatic systems. It is applied in Hyundai 912 excavators and Liebherr machinery with the following specifications:
* **Displacement:** 2 × 54.8 cm³ per revolution
* **Maximum operating pressure:** 350 bar
* **Peak pressure:** 400 bar
* **Maximum flow:** 2 × 137 liters per minute
* **Input power at maximum speed:** 160 kW
* **Maximum input torque:** 611 Nm
* **Approximate weight:** 82 kg
These specifications demonstrate the pump’s high capacity to provide the necessary pressure and flow for optimal hydraulic system performance in heavy machinery.
During repair of the A8VO55 pump, it is first removed from the hydraulic system, and all external connections and components are inspected. Precision tools such as micrometers and gauges are used to assess the dimensions and condition of internal parts including pistons, swash plate, cylinder block, and drive shaft. Any worn or damaged components are replaced. After component replacement, the pump is carefully reassembled and subjected to performance testing to ensure pressure, flow, and torque meet factory specifications.
Finally, once proper performance is confirmed, the pump is reinstalled
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| parsianrahbalandeh | 02155130771 |
| hydraulictak |
| Iran |
| 021-55732535 |
The accumulator used in concrete pumps is typically of the bladder type, designed to withstand working pressures between 250 and 350 bar. Its body is made of high-strength carbon steel with a tensile resistance above 950 MPa and is coated with anti-corrosion protection. The working volume is selected based on the pump’s capacity, usually ranging from 4 to 20 liters. The nitrogen pre-charge pressure is generally set between 90 and 120 bar to maintain hydraulic system efficiency.
The installation location of the accumulator in a concrete pump is on the main hydraulic line, close to the hydraulic pump, where it can absorb pressure surges and flow fluctuations. It is typically mounted near the control valve or directly on the hydraulic manifold, preferably in a vertical position. This installation ensures stable operation during sudden load changes and helps reduce wear on system components.
The capacity of the accumulator is determined by the hydraulic motor power and the pump’s output flow rate. For example, in concrete pumps with a delivery capacity of 60 to 80 cubic meters per hour, a 10-liter accumulator is commonly used. In larger models with outputs above 100 cubic meters per hour, 15- to 20-liter accumulators are applied. Proper capacity selection ensures sufficient
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| hydraulictak | 021-55732535 |
