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Mini Excavator Product

Overview

A mini excavator is a compact crawler digging machine, here under four tonnes, that brings full hydraulic excavator function to sites a full-size machine cannot reach. Rubber tracks spread its weight at low ground pressure and avoid tearing up finished surfaces, while a slewing upperstructure lets the boom dig through a full circle without repositioning the base. A front dozer blade adds backfilling and self-levelling. Its work is utility trenching, landscaping, foundations, demolition in confined spaces, and any job where a backhoe is too large.

The whole machine is hydraulically driven. A single diesel turns the pumps, and every motion — tracks, swing, boom, arm, bucket, blade — is an oil flow metered by valves the operator commands through two pilot joysticks. There is no mechanical driveline to the tracks and no engine-to-wheel gearbox.

How it works

Power begins at the Diesel Engine, a three-cylinder diesel whose flywheel drives the pumps in the Hydraulic System directly. The main variable-displacement pump supplies high-pressure oil, a small pilot pump supplies the low-pressure control signals, and the sectional control valve routes flow to whichever actuators the operator selects, with surplus heat shed through an oil cooler and tank.

The machine moves on its Undercarriage: two endless rubber tracks wrapped around drive sprockets, idlers and rollers on a welded frame. Each sprocket is turned by its own Travel Motor, a hydraulic motor geared down through a planetary reduction so the machine can crawl under full digging load or shift to a faster travel range. Driving one side faster than the other steers it; counter-rotating the tracks spins it on the spot.

Above the tracks, the Swing Assembly assembly carries the cab, engine and front linkage on a slew bearing. A hydraulic swing motor turns a pinion against the bearing's internal ring gear to rotate the upperstructure, letting the operator dig on one side and dump on another without moving the tracks.

The digging front is a three-piece linkage. The Boom raises and lowers on its lift cylinder; the Dipper Arm (the stick) curls in and out to set reach; and the Bucket Group rolls the toothed bucket through its four-bar linkage to break out and fill. All four front actuators are the same double-acting cylinder, sized for their station.

At the front of the tracks the Dozer Blade blade drops to backfill trenches and to level and stabilise the machine. The operator sits in the Operator Cab, a ROPS/TOPS canopy with a suspension seat, two pilot joysticks and a monitor. Powering the controls and starting the engine is the Electrical System system: a 12 V battery, an engine-driven alternator, a wiring harness and the engine controller.

Build & assembly graph

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Bill of materials

10 top-level lines · 97 rows shown · 218 parts total · indented to 3 levels
# Item / sub-assembly Part no. Qty/assy Ext. qty Parts Type
1 Diesel Engine 7 parts mini-excavator-engine 1 13 assembly
1.1 Engine Block mini-excavator-block 1 part
1.2 Piston mini-excavator-piston 3 part
1.3 Crankshaft mini-excavator-crankshaft 1 part
1.4 Fuel System 2 parts mini-excavator-fuel-system 1 4 assembly
1.4.1 Fuel Injector mini-excavator-injector 3 part
1.4.2 Injection Pump mini-excavator-fuel-pump 1 part
1.5 Radiator radiator 1 part
1.6 Coolant Pump coolant-pump 1 part
1.7 Oil Seal oil-seal 2 part
2 Hydraulic System 6 parts mini-excavator-hydraulics 1 17 assembly
2.1 Main Hydraulic Pump 4 parts mini-excavator-main-pump 1 7 assembly
2.1.1 Helical Gear Pair gear-pair 1 part
2.1.2 O-Ring Set oring-set 2 part
2.1.3 Oil Seal oil-seal 2 part
2.1.4 Ball Bearing ball-bearing 2 part
2.2 Pilot Gear Pump 3 parts mini-excavator-pilot-pump 1 5 assembly
2.2.1 Helical Gear Pair gear-pair 1 part
2.2.2 Oil Seal oil-seal 2 part
2.2.3 Ball Bearing ball-bearing 2 part
2.3 Main Control Valve mini-excavator-control-valve 1 part
2.4 Hydraulic Tank mini-excavator-hyd-tank 1 part
2.5 Hydraulic Oil Cooler mini-excavator-oil-cooler 1 part
2.6 Hydraulic Filter mini-excavator-hyd-filter 2 part
3 Undercarriage 6 parts mini-excavator-undercarriage 1 71 assembly
3.1 Welded Track Frame mini-excavator-track-frame 1 part
3.2 Rubber Track mini-excavator-rubber-track 2 part
3.3 Drive Sprocket mini-excavator-sprocket 2 part
3.4 Travel Motor 5 parts mini-excavator-travel-motor 2 28 assembly
3.4.1 Stator Assembly 3 parts + deeper › stator-assembly 2 3 assembly
3.4.2 Rotor Assembly 4 parts + deeper › rotor-assembly 2 19 assembly
3.4.3 Helical Gear Pair gear-pair 4 part
3.4.4 Ball Bearing ball-bearing 4 part
3.4.5 Oil Seal oil-seal 4 part
3.5 Track Idler mini-excavator-idler 2 part
3.6 Track Roller mini-excavator-track-roller 8 part
4 Swing Assembly 3 parts mini-excavator-swing 1 30 assembly
4.1 Slew Bearing 2 parts mini-excavator-slew-bearing 1 2 assembly
4.1.1 Ball Bearing ball-bearing 1 part
4.1.2 Slew Ring Gear mini-excavator-slew-ring-gear 1 part
4.2 Swing Motor 5 parts mini-excavator-swing-motor 1 27 assembly
4.2.1 Stator Assembly 3 parts + deeper › stator-assembly 1 3 assembly
4.2.2 Rotor Assembly 4 parts + deeper › rotor-assembly 1 19 assembly
4.2.3 Helical Gear Pair gear-pair 1 part
4.2.4 Ball Bearing ball-bearing 2 part
4.2.5 Oil Seal oil-seal 2 part
4.3 Swing Pinion mini-excavator-swing-pinion 1 part
5 Boom 3 parts mini-excavator-boom 1 7 assembly
5.1 Boom Weldment mini-excavator-boom-weldment 1 part
5.2 Hydraulic Cylinder 2 parts mini-excavator-cylinder 1 4 assembly
5.2.1 O-Ring Set oring-set 2 part
5.2.2 Oil Seal oil-seal 2 part
5.3 Pivot Pin & Bushing mini-excavator-pivot-pin 2 part
6 Dipper Arm 3 parts mini-excavator-arm 1 7 assembly
6.1 Arm Weldment mini-excavator-arm-weldment 1 part
6.2 Hydraulic Cylinder 2 parts mini-excavator-cylinder 1 4 assembly
6.2.1 O-Ring Set oring-set 2 part
6.2.2 Oil Seal oil-seal 2 part
6.3 Pivot Pin & Bushing mini-excavator-pivot-pin 2 part
7 Bucket Group 4 parts mini-excavator-bucket-group 1 13 assembly
7.1 Bucket 1 parts mini-excavator-bucket 1 4 assembly
7.1.1 Bucket Tooth mini-excavator-bucket-tooth 4 part
7.2 Hydraulic Cylinder 2 parts mini-excavator-cylinder 1 4 assembly
7.2.1 O-Ring Set oring-set 2 part
7.2.2 Oil Seal oil-seal 2 part
7.3 Bucket Linkage mini-excavator-linkage 1 part
7.4 Pivot Pin & Bushing mini-excavator-pivot-pin 4 part
8 Dozer Blade 3 parts mini-excavator-dozer 1 7 assembly
8.1 Blade Moldboard mini-excavator-blade 1 part
8.2 Hydraulic Cylinder 2 parts mini-excavator-cylinder 1 4 assembly
8.2.1 O-Ring Set oring-set 2 part
8.2.2 Oil Seal oil-seal 2 part
8.3 Pivot Pin & Bushing mini-excavator-pivot-pin 2 part
9 Operator Cab 4 parts mini-excavator-cab 1 13 assembly
9.1 ROPS/TOPS Canopy mini-excavator-canopy 1 part
9.2 Seat Assembly 5 parts seat-assembly 1 7 assembly
9.2.1 Seat Frame seat-frame 1 part
9.2.2 Seat Foam seat-foam 2 part
9.2.3 Seat Cover seat-cover 1 part
9.2.4 Seat Motor seat-motor 2 part
9.2.5 Seat Heater Mat seat-heater 1 part
9.3 Pilot Joystick mini-excavator-joystick 2 part
9.4 Operator Monitor 3 parts mini-excavator-monitor 1 3 assembly
9.4.1 Bare PCB pcb-bare 1 part
9.4.2 Microcontroller mcu 1 part
9.4.3 LCD Panel lcd-panel 1 part
10 Electrical System 7 parts mini-excavator-electrical 1 40 assembly
10.1 12 V Battery lv-battery 1 part
10.2 Alternator 3 parts mini-excavator-alternator 1 24 assembly
10.2.1 Stator Assembly 3 parts + deeper › stator-assembly 1 3 assembly
10.2.2 Rotor Assembly 4 parts + deeper › rotor-assembly 1 19 assembly
10.2.3 Ball Bearing ball-bearing 2 part
10.3 Wire Bundle wire-bundle 1 part
10.4 Connector connector 6 part
10.5 Relay relay 5 part
10.6 Engine Control Unit (ECU) mini-excavator-ecu 1 part
10.7 LED Work Light mini-excavator-work-light 2 part

Sourcing — likely vendors

Companies that make this · indicative price $15k–$2M · MOQ & lead are typical
VendorHQSpecialtyMOQLead time
🇺🇸Caterpillar
caterpillar.com ↗
Irving, US Construction & mining equipment made to order 16–28 wks
🇯🇵Komatsu
komatsu.com ↗
Tokyo, JP Construction & mining equipment made to order 16–28 wks
🇸🇪Volvo CE
volvoce.com ↗
Gothenburg, SE Construction equipment made to order 16–28 wks
🇨🇭Liebherr
liebherr.com ↗
Bulle, CH Cranes & heavy equipment made to order 16–28 wks
🇨🇳XCMG
xcmg.com ↗
Xuzhou, CN Construction machinery made to order 16–28 wks

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