Bosch Rexroth A2FO45/61R-VPB05 fixed-displacement axial-piston pump

Bosch Rexroth A2FO45/61R-VPB05 (material number R902198344) is a series 61 A2FO fixed-displacement bent-axis axial-piston pump for open hydraulic circuits. Nominal size 45 has a geometric displacement of 45.6 cm³/rev. The seal execution is FKM. It rotates clockwise when viewed at the drive shaft, delivering from S to B.

The execution has Parallel keyed shaft, DIN 6885 AS8 x 7 x 50 and a four-hole ISO 3019-2 flange. The pressure flange is 3/4 inch high-pressure-series SAE and the rear suction flange 1 inch standard-pressure-series SAE, with metric fastening threads. These flange sizes do not denote pipe threads.

For mineral-oil operation, the nominal high-pressure-port limit is 400 bar absolute and the maximum 450 bar absolute is limited to 10 seconds per operating period and 300 cumulative hours. The 2240 rpm reference maximum requires mineral oil, 1 bar absolute pressure at suction port S and recommended viscosity 16–36 mm²/s. The 4250 rpm limiting speed requires increased inlet pressure according to the source speed-ratio/inlet-pressure curve and compliance with the shaft-seal limit.

The mean case-to-ambient differential pressure must not continuously exceed 2 bar at normal operating temperature; the lower-speed curve governs any higher load. Peaks up to 10 bar last less than 0.1 second. Case pressure must be at least ambient pressure; the suction pressure allowance does not override the case-seal limit. Keep the case filled, bleed air before loading and connect the drain according to installation position. Left-hand rotation uses the port plate rotated 180° from the clockwise view.

The applicable original manufacturer technical reference is RE91401, edition June 2012. Representative manufacturer A2FO series 6 photograph; the illustrated shaft, size, rotation and ports may differ from this material-number execution.