T9T2 21D-60-15000 Excavator Motor OEM Hydraulic Travel Motor Excavator Machinery Parts

 Hydraulic Travel Motor Assy Final Drive T9T2 Excavator Swing Motor Part Excavator Machinery Parts

The excavator travel motor is a low-speed, high-torque hydraulic motor + reducer integrated device that drives the tracks (or wheels) to move, commonly known as the "final drive". It is installed on the inner side of the left and right drive wheels and is directly responsible for the machine's movement and steering.
1. Core functions
- Power conversion: It converts the high-pressure oil pressure energy sent by the hydraulic pump into mechanical energy to drive the tracks.
- Travel drive: It drives the drive wheels and tracks to achieve forward / backward / turning; the differential speed of the left and right motors enables turning.
- Speed reduction and torque increase: It is equipped with a planetary reducer to convert the high speed of the motor into the low speed and high torque required by the tracks.
- Braking and safety: It integrates a balance valve + mechanical parking brake to prevent "runaway" on downhill slopes and rolling back on slopes.

Installation Position and Appearance
Position: At the end of the track frame, on the inner side of the drive wheel, one on each side.
Appearance: Circular / cylindrical, with a flange plate connected to the drive wheel, and with a hydraulic oil pipe interface and an oil drain port.

Basic Structure (Integrated Assembly)
1. Hydraulic Motor: The mainstream type is a swashplate axial piston motor, featuring bidirectional rotation and two displacement gears.
2. Planetary Reducer: Adopts 3～4 stage planetary gears, with large reduction ratio and high output torque.
3. Counterbalance Valve (with cushioning / overflow function): Ensures smooth start and stop, prevents downhill runaway, and provides overload protection.
4. Mechanical Brake: Mostly wet multi-disc friction brake; spring-applied braking when power off/at neutral position, and pressure-released braking when hydraulic oil is supplied.
5. Output Shaft / Drive Wheel Connection: Directly drives the track drive wheel.