Excavator Parts K5V200DTP-OE11 9184686 Hitachi Hydraulic Main Pump Assy for ZAX450 ZX450
Our main products are Excavator Hydraulic Spare Parts, Hydraulic Main Pump, Swing Motor, Travel Motor, Final Drive Ass'y, Swing Device Ass'y, Swing Gearbox, Travel Gearbox, Gears, Regulators, Relief Valve, Fan Motor and other hydraulic items with genuine and aftermarket quality. Until now, our products have been exported to more than 198 countries and regions, spreading all over the Middle East, Southeast Asia, Africa, North America, South America, Europe and Oceania with our own brand "Belparts", which is highly praised by foreign customers and enjoys a high reputation.
Spare Parts List
| # |
Part No |
Part Name |
Qty. |
Price Request |
|
9184686 |
PUMP; PISTON |
1 |
|
| 001 |
4469526 |
. REGULATOR |
2 |
|
| 995 |
4444902 |
. SENSOR; ANGLE |
2 |
|
| 996 |
4274371 |
. O-RING |
2 |
|
Modern excavators predominantly use swashplate-type axial piston pumps. By electronically adjusting the swashplate angle via proportional valves, the piston stroke and pump displacement are precisely controlled. This enables instant response to operator commands: reducing flow for energy savings under light loads, while boosting pressure for heavy digging. Crucially, it balances power and efficiency, minimizing heat generation and extending equipment lifespan.
Engineered for extreme durability, these pumps feature hardened alloy pistons and copper-plated rotors to withstand high-frequency excavator shocks. Integrated pressure compensation and load-sensing controls adapt to dynamic working conditions. Beyond power transmission, they maintain stable pressure via closed-loop feedback, enabling smooth coordination of lifting, slewing, and digging--even in dusty or extreme-temperature environments.
Technical Specifications
The axial piston pump with a tilting swashplate is the undisputed workhorse for primary hydraulic circuits in modern excavators. Its core principle involves multiple pistons arranged axially (parallel to the drive shaft) within a rotating cylinder block. Each piston features a slipper pad riding on a non-rotating swashplate angled relative to the drive shaft's axis.
As the cylinder block rotates, the pistons reciprocate within their bores: moving outward during the half-rotation where the swashplate distance increases (suction stroke, drawing fluid from the inlet port), and being forced inward during the opposite half-rotation where the distance decreases (discharge stroke, pressurizing fluid to the outlet port).
The critical structural element for variable displacement is the adjustable swashplate angle. By changing this angle (typically via a hydraulic servo piston controlled by the operator or machine electronics), the stroke length of the pistons is altered. A larger angle increases piston stroke and thus pump displacement (flow rate), while a zero angle results in zero displacement.
Key structural components include the drive shaft, rotating cylinder block with precision piston bores, pistons with slippers, swashplate with tilt mechanism, valve plate (stationary, with kidney-shaped ports for inlet/outlet), and a robust housing.
In excavators, this design offers exceptional efficiency across a wide operating range, precise flow control essential for coordinated multi-function operation, and high-pressure capabilities needed for digging forces. Its ability to instantly vary flow from zero to maximum based on demand is fundamental to efficient excavator power management.
