Wheel excavator components

Wheel excavators are construction machinery with strong mobility and suitability for various operation scenarios. Their structure is designed around the two core functions of "operation" and "traveling movement", mainly including the following systems:

I. Power System

• Engine: The power core of a wheel excavator, usually a diesel engine (a few small models may use gasoline engines), which provides power for the machine's working devices, traveling system, hydraulic system, etc. The power of the engine directly affects the operating efficiency and traveling capability of the excavator. Since wheel excavators need to be capable of road driving, their engines are specially designed for stable rotation speed and fuel consumption control.
• Engine auxiliary systems: Including the fuel supply system (fuel tank, fuel pump, filter), lubrication system (oil pump, oil filter), cooling system (water tank, radiator, fan), exhaust system (exhaust pipe, muffler), etc., to ensure the stable operation of the engine.

II. Chassis System (Traveling System)

• Axles and tires: Usually 4-wheel or 6-wheel drive (mostly all-wheel drive to enhance off-road capability). The tires are engineering-specific wear-resistant ones with wide treads and deep patterns, suitable for various road surfaces such as construction sites and highways, balancing load-bearing capacity and driving stability.
• Transmission: Divided into manual transmission or automatic transmission. It adjusts the traveling speed through gear shifting to meet different needs of road driving (higher speed) and movement in operation sites (lower speed).
• Drive axles: Including front axle and rear axle, which transmit the engine power to the wheels and bear the weight of the entire machine and the impact force during operation.
• Steering system: Mostly hydraulic power steering. Some large wheel excavators adopt articulated steering (the middle part of the body can bend) to reduce the turning radius and improve the flexibility on site.
• Brake system: Including service brake (foot brake) and parking brake (hand brake). Some models are equipped with auxiliary brakes (such as exhaust brake) to ensure safe braking during driving and operation.

III. Working Device (Operation System)

• Boom: A large metal arm connecting the machine body and the stick, which can be driven up and down by hydraulic cylinders to control the operation radius and height.
• Stick: The component connecting the boom and the bucket, which can be extended, retracted, or rotated by hydraulic cylinders to further adjust the operation range.
• Bucket: The tool at the end of the working device. According to different purposes, it is divided into standard buckets (for earthwork), rock buckets (for hard materials), grab buckets (for grabbing materials), breakers (for breaking concrete/rock), etc., which can be replaced quickly.
• Hydraulic cylinders: Including boom cylinders, stick cylinders, and bucket cylinders, which are the power source of the working device, driving mechanical movements through the pressure of hydraulic oil.

IV. Hydraulic System

• Hydraulic pump: Converts the mechanical energy of the engine into hydraulic energy, providing high-pressure hydraulic oil for the entire system (common types are gear pumps and piston pumps).
• Hydraulic motor: Used in the slewing mechanism and traveling system (such as hydraulically driven wheels) of some models, converting hydraulic energy into mechanical energy.
• Control valve group: Including main control valve, directional valve, etc. It precisely controls the movements of the working device, slewing, and traveling by controlling the flow, direction, and pressure of hydraulic oil.
• Hydraulic oil tank and pipelines: Store hydraulic oil and transport it through pipelines, equipped with filters (oil filters) to purify the hydraulic oil and prevent impurities from damaging precision components.
• Hydraulic cylinders: As described in the "working device" above, they are the executive components of the hydraulic system.

V. Slewing Mechanism

• Slewing bearing: A large bearing structure that connects the upper turntable and the lower chassis, bearing vertical load, horizontal load, and overturning moment.
• Slewing motor: A hydraulically driven motor that drives the turntable to rotate through gear transmission, equipped with a braking device to control the start and stop of rotation.

VI. Operation and Control System

• Cab: The space for the operator to operate, equipped with a seat, steering wheel (or joystick), control handle (to control the working device), instrument panel (displaying parameters such as engine speed, oil quantity, water temperature), operation buttons (such as horn, lights, air conditioning), etc. Some high-end models have suspension seats and shock-absorbing cabs to improve comfort.
• Control handle: Operates the movements of the boom, stick, bucket, and slewing mechanism by controlling the hydraulic valve group. Its precision directly affects the operation efficiency.
• Electronic control system: Some modern wheel excavators are equipped with ECU (Electronic Control Unit), which monitors the status of the engine and hydraulic system, realizes functions such as fault alarm and fuel consumption statistics, and some models support remote monitoring.

VII. Body Structure and Auxiliary Systems

• Upper turntable: A platform where the engine, cab, and working device are installed. It is connected to the chassis through the slewing mechanism and can rotate.
• Counterweight: A heavy iron block at the tail of the turntable, which balances the overturning moment during the operation of the working device and ensures the stability of the entire machine.
• Electrical system: Including battery, generator, wire harness, lights (work lights, turn signals, headlights), horn, wiper, etc., to meet the needs of starting, lighting, signal prompt, etc.
• Safety devices: Such as cab roll-over protective structure (ROPS), falling object protective structure (FOPS), reverse image, acousto-optic alarm, etc., to ensure the safety of operators.