9197338 Original Excavator Swing Motor for ZX120

The original swing motor part number 9197338 is the core actuator of the swing system for Hitachi ZX120 series medium-sized excavators (such as ZX120-5A, ZX120-6, etc.). It may have interchangeability with the rotary motors of models on the same platform as ZX120 (such as ZX130, ZX135), but specific universality depends on Hitachi's official parts manual or dealer inquiries. This motor is responsible for driving the upper turntable to achieve 360 ° full rotation, and its output shaft meshes with the slewing support ring gear through a planetary gear reducer. When ordering, the complete model and serial number of the equipment must be provided to ensure that its installation interface, reduction ratio, and control oil circuit are fully matched with the original system.

This product is an original rotary motor assembly, usually made of cast iron housing, integrating a slanted disc or slanted shaft axial piston hydraulic motor and a multi-stage planetary gear reduction mechanism. Internally, it includes precision friction pairs such as plungers, cylinder bodies, and distribution plates, and is equipped with normally closed hydraulic brakes, safety relief valves, oil replenishment valves, and anti reverse valves to ensure smooth rotation, reliable braking, and the ability to absorb impact when stopping. As an original component, its processing accuracy, heat treatment process, and sealing material are strictly matched with Hitachi's original hydraulic system, ensuring high efficiency, low leakage, and long service life under high pressure (usually working pressure exceeding 25MPa) and high load conditions.

It is recommended to check the cleanliness of the hydraulic oil (NAS level 9 or below) and the oil level of the rotary gear every 500 working hours; Monitor for any abnormal noise or stuttering during rotation. Regular maintenance: Replace the gear oil (usually GL-5 80W-90) of the rotary gearbox every 1000 working hours, and check the tightening torque of the motor mounting bolts. Fault prediction: If there is slow rotation, weakness, drifting or abnormal noise after stopping, it may be due to plunger wear, valve plate strain or brake piston seal failure, and it needs to be repaired in a timely manner.