——Laser cladding technology enables equipment to upgrade its performance throughout its life cycle

In the fields of tunneling, mining and heavy material handling, large equipment such as shield machines, crushers, coal mining machinery, etc. have long been subjected to the combined effects of extreme wear, impact loads, and corrosive media, resulting in frequent failure of key components and high operation and maintenance costs. Relying on laser cladding technology as the core, combined with additive manufacturing (AM) and surface functional enhancement technology, our company provides global engineering machinery customers with a full chain of services from old parts repair to new product pre-strengthening, achieving a 3-8 times increase in component life and a more than 60% reduction in downtime losses, helping customers achieve cost reduction and efficiency improvement under harsh working conditions.

Ⅰ. Analysis of industry pain points and core component requirements

1. Shield machine system

Cutterhead tool/roller bearing seat: rock and soil abrasive wear (hardness up to Mohs 7) and impact fatigue, requiring a super wear-resistant coating with a surface hardness ≥HRC 60.

Screw conveyor blades: soil friction and mud corrosion, requiring a dual-function coating that is wear-resistant and chloride ion-resistant.

Main drive seal ring: high-pressure (≥10bar) mud penetration, requiring repair of the sealing surface and enhanced anti-fretting wear performance.

2. Crushing and screening equipment

Jaw crusher jaw plate/cone crusher liner: high-stress impact wear (quartzite, basalt), requiring a tungsten carbide-based coating with excellent impact toughness.

Vibrating screen support beam: high-frequency impact and alternating stress of ore particles, requiring a composite coating to resist fatigue crack propagation.

Impact crusher rotor/hammer: Material impact with a linear speed of 60m/s requires a gradient structure coating (high hardness surface layer + tough bottom layer).

3. Coal mining machinery

Coal mining machine pick/scraper conveyor sprocket: Wear of coal gangue and corrosion in the humid environment underground require wear-resistant and corrosion-resistant integrated coating.

Hydraulic support column: High-pressure emulsion corrosion and micro-wear require laser cladding of stainless steel alloy to restore surface finish.

Fan impeller: Sulfur-containing gas corrosion and dust erosion require acid-resistant (pH 2-4) nickel-based alloy coating.

Ⅱ. Laser cladding technology advantages and material selection

1. Core technical advantages

High bonding strength: Metallurgical bonding interface strength ≥ 400MPa (ASTM C633), completely solving the problem of spalling of traditional cladding layer.

Micro-deformation repair: Heat-affected zone ≤ 0.3mm, substrate temperature controlled below 200℃ to avoid thermal distortion of large structural parts.

Composite functional design: supports “gradient material + bionic structure” coating, for example:

Wear-resistant-friction-reducing composite layer: surface WC-Co (hardness HRC 65) + middle layer NiCrBSi (self-lubricating) + bottom layer Inconel 625 (fatigue resistance).

Corrosion-resistant-impact composite layer: Hastelloy C276 (acid corrosion resistance) + FeCrNiMoB (tough buffer layer).

Material system and performance adaptation

3. New product pre-strengthening process

For newly manufactured parts, laser cladding can simultaneously realize the integrated manufacturing of substrate forming + functional coating:

Shield machine cutterhead tool: substrate 42CrMo + cladding WC-12Co coating, hardness increased from HRC 25 to HRC 65, excavation life extended from 5 kilometers to 30 kilometers.

Mining truck cargo box lining: Q345 steel substrate + cladding FeCrNiMoB wear-resistant layer, impact wear life increased by 5 times, reducing the frequency of lining replacement.

III. Full process service system and quality assurance

1. Service process

Damage diagnosis:

Use industrial endoscope, 3D scanning (accuracy ±0.05mm) and hardness gradient analysis to accurately locate the failure area.

Based on AI algorithm, predict the remaining life and generate a repair priority report.

Process design:

Match the material library (including 50+ alloy powders) and process parameters (power, powder feeding rate, scanning strategy).

Simulate the molten pool morphology and thermal stress distribution to optimize the coating structure.

On-site implementation:

Use 6kW-20kW fiber laser, equipped with a six-axis robot, to achieve adaptive cladding of curved surfaces (such as repairing the curved surface of the shield machine cutter head).

Synchronously integrate the powder recovery system, and the material utilization rate is ≥95%.

Post-processing and certification:

Shot peening: Improve the fatigue strength of the coating (ISO 1143).

Non-destructive testing: penetrant testing (ASTM E1417), ultrasonic testing (EN 12680-3).

2. International standard certification

Material certification: Powder complies with ASTM F3056 (nickel-based alloy) and ISO 4490 (tungsten carbide).

Process standards:

Wear-resistant coating: ISO 18520 (laser cladding repair acceptance specification).

Corrosion-resistant coating: NACE MR0175 (anti-hydrogen sulfide corrosion).

IV. Global cooperation cases and benefits

1. Nordic shield machine cutter repair project

Problem: Granite strata cause the cutter to be replaced every 2 kilometers on average, with a single cost of more than 500,000 euros.

Solution: Laser cladding WC-12Co coating (thickness 2.5mm), hardness HRC 65, and anti-granite wear life increased to 15 kilometers.

Results: The customer’s comprehensive tunnel engineering cost was reduced by 40%, and it was certified by TÜV Rheinland of Germany.

2. Australian iron ore crusher jaw plate strengthening

Problem: The jaw plate is replaced every 3 weeks, and the downtime loss is 120,000 Australian dollars per day.

Solution: The new product is pre-clad with FeCrNiMoB+WC gradient coating, and the impact wear life is extended to 6 months.

Results: Annual spare parts cost savings of 2.8 million Australian dollars, and production efficiency increased by 25%.

3. Corrosion resistance upgrade of scraper conveyor sprocket in South American coal mines

Problem: The humid environment underground causes the sprocket to rust and jam after 3 months.

Solution: Laser cladding Hastelloy C276 coating (thickness 1.8mm), salt spray corrosion resistance life of more than 2 years.

Achievements: Equipment availability increased from 65% to 92%, and customer investment return cycle shortened to 8 months.

V. Technology extension and future layout

Intelligent equipment: Develop AI-driven laser cladding robots, monitor the temperature and morphology of the molten pool in real time, dynamically adjust process parameters, and improve processing efficiency by 30%.

Green manufacturing: Reduce carbon emissions by 75% and metal resource consumption by 90% by repairing and replacing new parts, in line with EU CE certification and carbon tariff requirements.

Customized R&D: Jointly develop special alloy powders with customers, such as anti-sticking coal coatings (low surface energy materials) and high-temperature oxidation-corrosion coupling coatings.

Reshape the vitality of construction machinery with laser cladding – With innovative technology and a global service network, we help customers achieve “zero unplanned downtime” under extreme working conditions and promote the heavy equipment industry towards an efficient and sustainable future.