M5X180CHB rotary motor assembly ZAX330 rotary motor 4419718

This high-precision heavy-duty rotary motor assembly component uses Kawasaki's classic M5X180CHB high-pressure inclined disc plunger motor as its core, corresponding to Hitachi's official original core part number 4419718. This assembly is specially designed for Hitachi's medium to large heavy-duty hydraulic excavators, perfectly matching 33 ton core flagship models such as ZX330, ZAX330, and EX330-3. It serves as the absolute axis for 360 ° rotation and precise braking of the upper body. The product is based on first principles for high-pressure fluid dynamics optimization design, fully bearing the frequent directional impact under heavy load excavation, ensuring absolute certainty of output torque. The physical dimensions of the product packaging are approximately 540mm × 410mm × 430mm, with an overall net weight of approximately 95kg. The original factory standard position is precisely aligned.

"Extreme cleaning and alignment: Noise reduction and dust removal treatment are required for the unpacking and installation environment. Before installation, the mating surface of the Hitachi rotary reducer must be thoroughly cleaned to ensure precise and stress free meshing of the output gear shaft. All high-strength fastening bolts must be tightened symmetrically and cross with torque wrenches strictly according to the specified torque.

Forced oil injection (core avoidance pit): Do not connect the high-pressure oil pipe to the wrong drain pipe (Case Drain). Before starting the engine, it is necessary to fill the top of the swing motor housing with clean hydraulic oil through the bleed/fill port. It is strictly prohibited to start dry grinding, otherwise the internal plunger and distribution plate will undergo irreversible physical erosion within 3 seconds of ignition.

No load micro motion transition: After the first ignition, control the upper body to perform a slow rotation micro motion at a small angle left and right for 10-15 minutes in an unloaded state, thoroughly exhaust the circuit air, and confirm the thermodynamic stability before gradually applying the full working load."