Core mining and crushing equipment including tunnel boring machines, jaw crushers, cone crushers, ball mills, scraper conveyors and vibrating feeders are widely deployed in underground coal mines, metal mines and non-metal mines. They operate under extreme working conditions: violent intermittent impact loads, floating large quantities of high-hardness rock and mineral dust, humid water seepage in roadways, persistent high-frequency equipment vibration, sharp temperature difference between day and night and uninterrupted 24-hour mining and crushing. The shutdown cost of mining production lines is extremely high. Once bearings fail suddenly, mining and crushing processes halt immediately. It takes a long time for personnel evacuation and equipment maintenance underground, and accumulated ore cannot be transported, leading to massive production losses. Ordinary cylindrical roller bearings cannot withstand harsh mining environments and become a common pain point for mining areas. Violent impact loads are continuously generated during ore crushing and rock tunneling. Ordinary bearings lack sufficient matrix toughness and are prone to raceway indentation, fatigue peeling or even fracture under long-term alternating impact, resulting in intensified equipment vibration and out-of-control crushing particle size. Hard rock dust and fine slag spread throughout mining sites. With high hardness and strong grinding capacity, fine rock powder penetrates into bearings through simple seals, mixes with grease to form powerful abrasive medium and rapidly wears raceways and rolling elements. Roadways generally suffer from water seepage and water spray. Water vapor continuously invades bearing cavities, causes grease emulsification and failure, and induces rust and pitting corrosion. Long-term high-frequency vibration aggravates internal stress concentration and accelerates bearing precision attenuation. Underground maintenance space is narrow with strict safety management. Bearing replacement procedures are complicated, and frequent shutdown for parts replacement continuously increases mine operation and maintenance costs.

Focusing on transmission supporting field for mining excavation and crushing equipment, Japan NMT specially develops ultra-heavy-load impact & rock-dust resistant wear-resistant long-life cylindrical roller bearings dedicated for mining machinery to solve industry pain points of ordinary mining bearings such as insufficient impact resistance, easy ingress of hard rock dust, vulnerability to rust caused by underground water seepage, susceptibility to fatigue under continuous vibration and short service life under long-term heavy loads. Through five core upgrades including ultra-high-toughness forged alloy steel matrix, heavy-duty multi-layer labyrinth dust-proof waterproof composite sealing, deep surface strengthening heat treatment for raceways, hydrolysis-resistant dust-resistant heavy-duty lubrication and alternating impact load stress equalization optimization, it fully adapts to harsh working conditions of tunneling, crushing and conveying equipment with extreme impact, hard rock dust and underground humid seepage. It fundamentally solves problems including bearing impact damage, rock dust abrasion, water vapor rust and premature failure, stabilizes operating status of mining and crushing equipment and guarantees continuous mine production.

Core Product Advantages

1. Ultra-high-toughness forged alloy steel matrix withstands violent mining impact heavy loads: Adopting high-purity forged bearing alloy steel specially for heavy mining equipment with deep multi-layer quenching & tempering strengthening heat treatments to greatly improve matrix toughness, compressive strength and impact fatigue resistance. It bears instantaneous violent impact loads during ore crushing and roadway tunneling for a long time, effectively restraining raceway plastic indentation, fatigue peeling and component cracking.

2. Heavy-duty multi-layer labyrinth dust-proof waterproof composite sealing blocks ingress of rock dust and underground seepage water: Equipped with exclusive heavy-duty labyrinth and thickened wear lip sealing system for underground mining conditions. It resists vibration and is not easy to fall off or deform, intercepts hard rock & mineral dust and slag fragments layer by layer, blocks roadway spray water and seepage from penetrating into bearings, prevents dust from mixing with grease to form abrasive paste, avoids grease emulsification caused by water absorption, and greatly lowers risks of internal abrasive wear and corrosion.

3. Deep surface strengthening heat treatment for raceways improves wear and fatigue resistance: Deep hardening strengthening treatment is applied on raceways and rolling elements to optimize metallographic structure, enhance surface hardness, pitting resistance and spalling resistance. It effectively slows precision attenuation under continuous abrasion by hard rock dust and long-term strong vibration and extends service life of bearings underground.

4. Hydrolysis-resistant dust-resistant heavy-duty lubrication system adapts to humid and changeable underground environment: Custom heavy-duty lubrication formula developed for high-dust and water-spray underground mining conditions features excellent anti-dust pollution performance and hydrolysis & wash resistance. It is not easily deteriorated by mineral dust contamination or emulsified by water vapor, continuously forms high-strength protective oil film, adapts to long uninterrupted heavy-duty operation and extends underground lubrication maintenance intervals.

5. Optimized structure for alternating impact loads evenly disperses vibration stress: Optimizing roller arrangement and internal clearance matching parameters to improve stress distribution under continuous impact loads, relieve local stress concentration brought by mining and crushing operations, slow precision loss caused by long-term high-frequency vibration and reduce abnormal vibration and noise of equipment.

Application Scenarios

Tunnel boring machines, jaw crushers, cone crushers, hammer crushers, ball mills, rod mills, scraper conveyors, vibrating feeders, ore belt conveyors, roll shaft supporting and transmission parts of various open-pit and underground mining & crushing equipment.

Precision Quality Assurance

NMT heavy-duty cylindrical roller bearings for mining machinery are manufactured strictly in accordance with Japanese heavy mining equipment manufacturing standards. Selected special bearing steel with ultra-high toughness, impact resistance, wear, dust and waterproof performance undergoes ultimate impact durability test, rock dust sealing durability test, roadway water spray corrosion test, long-term high-frequency vibration fatigue test and continuous heavy-load durability test. The products feature ultra-high load limit, outstanding impact resistance and stable dust-proof & waterproof sealing and wear resistance, fully adapting to 24-hour continuous mining and crushing conditions with hard rock dust, violent impact and humid seepage in underground and open-pit mines.

Product Range

Heavy-duty impact-resistant cylindrical roller bearings for tunneling machines, wear-resistant dust-proof bearings for jaw & cone crushers, long-life supporting bearings for ball mills, waterproof rock-dust resistant bearings for scraper conveyors, low-vibration stable bearings for vibrating feeders, customized non-standard ultra-heavy-load bearings for heavy mining equipment.

Brand Strength

Japan NMT focuses on R&D and manufacturing of bearings for heavy mining excavation and crushing under working conditions of violent impact loads, hard rock & mineral dust, underground humid water seepage and persistent strong vibration, specializing in performance optimization under scenarios of instantaneous heavy impact, solid dust abrasion, humid water spray corrosion and long-term alternating loads. With Japanese ultra-tough forged steel heat treatment technology, exclusive heavy-duty dust-proof waterproof sealing technology for underground mining and strict extreme mining condition simulation testing system, it accurately solves industry problems of mining bearings such as abrasive wear failure caused by rock dust, impact fracture, water seepage rust and frequent shutdown maintenance replacement, supplying ultra-high-load, impact-resistant, dust & waterproof long-life core transmission components for global coal, metal and non-metal mining & crushing industries.