1. Product Overview
This genuine Bosch Rexroth part with OEM part number R902211027, full model A22VG045HT1005M140BRNB2S73FB2S4A-Y, is a heavy-duty tandem axial Hydraulic piston pump, serving as the core main hydraulic pump to power closed-loop hydrostatic hydraulic system for compact construction machinery. It integrates two independent variable pumping assemblies in one monoblock housing, with built-in charge pump, relief valves, flushing valve and proportional servo control, eliminating extra valve blocks and simplifying the whole hydraulic system layout for skid steer loaders, backhoe loaders and rough-terrain forklifts. As a premium Hydraulic piston pump, it delivers precise flow and pressure regulation to guarantee stable running of the complete machine’s walking hydraulic system under heavy loads.
Core Identification
- Genuine Rexroth PN: R902211027
- Complete Model: A22VG045HT1005M140BRNB2S73FB2S4A-Y
- Category: Tandem swashplate variable Hydraulic piston pump
- Position: Master drive hydraulic pump of closed hydrostatic hydraulic system
2. Model Code Breakdown
A22VG045HT1005M140BRNB2S73FB2S4A-Y
1. A22VG: Series code for tandem axial piston pump dedicated to closed-circuit hydraulic system
2. 045: Single pump displacement 45cc/rev, double pump total displacement 2×45cc
3. H: Electro-hydraulic proportional servo control mode for accurate regulation of the hydraulic pump output
4. T: Through-drive shaft design for mounting auxiliary gear pumps to supplement the whole hydraulic system
5. 1005: OEM customized calibration code for flow-pressure curve matching host machine’s hydraulic system
6. M1: External mechanical limiter to lock maximum displacement of the Hydraulic piston pump
7. 40: SAE 40 standard flange mounting specification
8. B: Counter-clockwise rotation (view from drive shaft end)
9. R: Built-in bi-directional high-pressure relief valves to protect the hydraulic system from overpressure damage
10. N: NBR rubber seals compatible with standard mineral hydraulic oil
11. B2: Integrated charge pump & check valve assembly to replenish leakage oil for closed hydraulic system
12. S73: Standard solenoid mounting base for electric control signal input
13. FB2: Integrated flushing valve to discharge high-temperature oil and cool the hydraulic system
14. S4A: SAE involute spline drive shaft
15. -Y: Exclusive OEM customized version, non-interchangeable with generic A22VG045 hydraulic pump
3. Key Technical Parameters
Item Specification
Single Pump Displacement 45 cc/rev (Hydraulic piston pump core parameter)
Continuous Rated Pressure 380 bar
Peak Intermittent Pressure 420 bar
Rated Speed 3300 rpm
Max Intermittent Speed 3800 rpm
Built-in Charge Pump Displacement 12 cc/rev
Charge Pressure 22~28 bar (factory preset for hydraulic system replenishment)
Drive Shaft SAE involute spline shaft
Mounting SAE 4-bolt flange
Compatible Fluid ISO VG46 / VG68 anti-wear hydraulic oil
Operating Temperature -20℃ ~ +95℃
Net Weight 55 KG
4. Working Principle
Driven by the engine main shaft, this dual-unit Hydraulic piston pump generates independent hydraulic flow for left and right travel motors to realize skid steering. Electric signals from the operation handle actuate the servo valve to tilt the pump swashplate, adjusting output flow and oil direction of the hydraulic pump, so as to control forward/backward movement and stepless speed of the machine.
The integrated charge pump supplements leaked oil for the closed hydraulic system; relief valves prevent sudden pressure surges; the flushing valve cycles hot oil out to cool down the whole hydraulic system, forming a fully self-protected closed hydrostatic loop.
5. Product Features
1. High integration: All auxiliary valve groups built into the Hydraulic piston pump body, reducing pipeline connections and fault points of the hydraulic system
2. Heavy-duty internal components: Forged cylinder block, bronze valve plate and hardened piston slippers enhance the durability of the hydraulic pump in dusty construction sites
3. Precise proportional control: Smooth start & stop, sensitive steering to optimize the response of the whole hydraulic system
4. Through-drive expansion: Rear shaft can install auxiliary pumps to supply working attachments’ hydraulic system
5. Exclusive OEM part: R902211027 is tailor-calibrated for designated hosts; cannot be replaced by ordinary A22VG045 hydraulic pump directly
6. Application Scenarios
It is the original matched hydraulic pump for mainstream skid steer loaders, backhoe loaders, rough-terrain forklifts and mini road rollers. This professional Hydraulic piston pump forms the core closed-loop hydraulic system to realize independent wheel drive and flexible steering, widely used in construction, agriculture and material handling fields.
