EN
Motor Graders
Periodic inspection of motor graders: mouldboard circle drive, tilt links, ART automation, undercarriage and brake-safety checks with signed engineer reports.
Motor grader periodic inspection is the at-least-annual examination and testing by authorised engineers of graders positioning a long mouldboard on a rotating circle for road-subgrade finishing: blade tilt lift cylinders, the circle drive gear, ART automatic grading equipment, frame-joint undercarriage connections, travel-brake and operator protection-vision systems are assessed. The grader is designed for fine work yet remains a moving machine combining tip-over, cutting-friction and automation faults; the control audits these layers together.
Inspection Items
- Mouldboard and circle: Corner-cutting edge wear and bolt integrity; circle top-bottom drive gear backlash-wear, tilt cylinders and circle worm gear; slew brake and locking behaviour.
- Front blade (predozer) and ripper (if any): Cylinder-hose leakage, pin-bushing clearance, lock position safety.
- Frame hinge and suspension: Articulation cylinders and auto lock; front-rear body torsion zone; bogie rod-end rod integrity; wheels and rim bolts.
- Drivetrain-brake-engine: Torque converter-gearbox behaviour, differential lock, park brake; reverse lining and exhaust-retarder cooling; overspeed cut-off.
- ART-automation and cabin: Laser/GNSS level sensors, grade sensor-hydraulic matching; calibration trace of the 3D display; cabin ROPS/FOPS, seatbelt interlock, rear camera and blind spot warnings; work lighting.
Periodic Tests and Measurements
The circle drive test begins with a free full rotation: skipped teeth, rhythmic binding and abnormal sound are scanned; the circle brake stop behaviour is measured. Tilt-shift cylinders run drift and load-hold tests; control link clearance produces vibration in operation. In the ART check, sensor-hydraulic matching deviation is measured against a known grade reference (manufacturer ± band); calibration history is questioned. At the frame joint, full left-right motion and auto lock are verified; a leaking cylinder makes the machine "wander". The brake test covers loaded-reverse stopping distance and gradient holding; thermography scans circle gearbox-differential hot spots. Cabin vision analysis is reported with a blind spot map.
Legislation and Standards
Graders are subject to at least annual periodic control under Law No. 6331, the Work Equipment Regulation and the 2006/42/EC Machinery Directive. Technical references: general safety TS EN 474-1 and grader-specific TS EN 474-7, rollover protection ISO 3471/ISO 10269, visibility ISO 5006, fluid power ISO 4413 and braking ISO 3450. Site traffic planning on road works (pedestrian-machine separation, speed limits) appears as a warning in the report; night shifts require lighting and reflective marking as administrative conditions.
Risks, Recommendations and Outcome
Leading risks: blade slew under load when the circle brake slips (sudden torsion and throw), wrong elevation dig from ART calibration drift, tip-over on sloped cut edges and pedestrian run-over in reverse. Tilt links must not stay greasy-jammed; a worn circle gear is replaced as a matched set. The operator should work perpendicular rather than parallel to the cut edge and balance automation trust with manual verification. Facilities are recommended daily circle-brake tests, periodic ART calibration records, tyre-track pressure control and vision-alarm audits. At the end of the examination a signed report is issued. Grader controls are in our Construction Machinery group; see Asphalt Pavers and Soil Stabilization, or contact us for a programme.
FAQ on Motor Graders
A motor grader fine-grades-shapes with a central rotating blade-circle and works through front-rear chassis articulation and side shift. Risks: blade-circle rotating mechanism jam-break-throw (tilt-cutter), articulation-side-shift hydraulic leak-loss of control, blade-angle jump-trajectory drift while cutting, the long-chassis turning blind spot for pedestrians, and front-rear differential (6x4) brake mismatch. TS EN 474; yearly periodic control.
Circle-gearbox-gear-tightening-bolt-wire wear; tilt-lift-swing cylinders-hydraulic-leak-burst-valve-drop prevention; blade edge wear-tear-cleanliness. Articulation cylinder-bushing-play-pin wear-clearance, side-shift mechanism, front-rear frame-weld-crack-fatigue; front-rear steering angle-sync play, differential lock-steer, brake balance-distance (loaded-empty)-parking hill; lighting-signal-rear alarm-camera-horn; tyre-rim pressure wear; power-shift cooling temperature (thermal); ROPS-cabin belt; hydraulic level-filter-pressure; blade-change safety rule label. Results are a per-machine report.
Cracked-loose circle-gearbox bolt (throw-stop), missing-leaking tilt-lift burst valve (blade fall), excessive articulation pin-bushing play-hydraulic leak (loss of control-lateral tip), mismatched front-rear steer angle-faulty lock (machine drift), brake imbalance-not holding-parking slipping, cracked-over-pressure tyre-rim, dead lighting-signal-rear alarm, no mechanical lock for blade change: red tag. Return after manufacturer verification-test; blade edge change under LOTO (mechanical prop lock).
Operator licence; a daily pre-operation card (blade-circle-leak-articulation-brake-lighting-rear alarm-belt). Grading rule (slope-ground-water-condensation-slip), turning radius-front chassis-blind-spot-pedestrian separation, crest approach speed, long-body carrying-closed-road distance. Maintenance per manufacturer calendar (circle gear lubrication-hydraulic filter-brake pads-tyre rim). Report-log thermal-fault-certificate enter the OHS file on the yearly periodic control.