Single & twin-screw extruders, underwater pelletizers, internal mixers and cutting pelletizing units are core production equipment in rubber and plastic processing industry. Screw supports, reduction gearbox output shafts and pelletizing roller supports operate under harsh working conditions: ultra-large continuous combined loads, high-temperature thermal radiation from barrels, floating ultra-fine powders such as carbon black and calcium carbonate additives, persistent axial thrust generated during screw extrusion and uninterrupted all-weather continuous processing. Rubber and plastic extrusion lines demand extremely high continuity. After equipment shutdown, materials tend to solidify and agglomerate inside barrels. Restart requires long-time cleaning, heating and commissioning, resulting in massive raw material scrapping, disrupted production rhythm and remarkable economic losses. Ordinary tapered roller bearings cannot adapt to harsh high-temperature and dust-filled environments in rubber & plastic workshops, becoming a common pain point for machinery manufacturers and processing factories. Screw extrusion generates strong continuous axial thrust and radial loads, and load fluctuates along with materials. Ordinary bearings have insufficient fatigue resistance and tend to form raceway indentation and rolling element surface peeling under long-term cyclic loads, triggering screw runout and impairing melt extrusion stability and product quality. Heat continuously transfers from barrels, raising ambient temperature around bearings. Conventional lubricating grease is prone to thermal oxidation, coking and hardening, leading to abnormal temperature rise of bearings. Fillers including carbon black, talcum powder and calcium powder are added during production. These fine particles feature abrasive properties and cannot be fully blocked by simple seals. Dust penetrates into bearing cavities, mixes with grease and forms persistent abrasive medium that continuously wears raceways and rolling elements. Ultra-fine powder easily adheres to seal lips and gradually invades seal gaps to accelerate seal aging and failure. Disassembly and assembly of large extruders are complicated, and shutdown for bearing replacement and barrel cleaning greatly reduces effective production hours and continuously increases factory operation costs.

Focusing on transmission supporting field for rubber & plastic extrusion and pelletizing equipment, Japan NMT specially develops high-temperature dust-proof heavy-duty tapered roller bearings dedicated for extrusion & pelletizing lines to solve industry pain points of ordinary extruder bearings such as insufficient heat resistance, easy ingress of ultra-fine filler dust, fatigue damage induced by screw axial thrust, high-temperature grease coking and limited service life under continuous pelletizing operation. Taking advantage of bidirectional linear load-bearing structure of tapered rollers, combined with five core upgrades including heat-resistant high-toughness refined bearing alloy steel, multi-layer labyrinth high-temperature dense dust-proof composite sealing, deep-hardening super-finishing technology for raceways, high-temperature dust-resistant long-life lubrication and precise clearance matching for rubber & plastic working conditions, it fully adapts to harsh conditions of extruders and pelletizers with high-temperature radiation and interference of ultra-fine filler dust. It fundamentally solves problems including high-temperature grease coking, abrasive wear by powder, fatigue spalling and seal leakage, stabilizes screw rotation precision and guarantees long-cycle continuous production of rubber & plastic extrusion and pelletizing lines.

Core Product Advantages

1. Bidirectional ultra-large combined load bearing withstands persistent screw axial thrust and load fluctuation: Adopting tapered roller linear contact structure, it bears high-strength radial loads and continuous axial thrust simultaneously with uniform load distribution in contact zones. It buffers load impact caused by material fluctuation, restrains excessive unilateral raceway wear induced by screw eccentric load, stably controls axial play of shaft systems and ensures uniform and stable melt extrusion.

2. Heat-resistant high-toughness bearing steel matrix delivers long-term fatigue and wear resistance under high temperature: Selected high-purity heat-resistant bearing alloy steel specially for rubber & plastic processing equipment undergoes deep quenching & tempering heat treatments to optimize high-temperature metallographic structure, improve matrix toughness, compressive strength and wear resistance under thermal conditions. It withstands long-term alternating loads from screws and delays raceway fatigue damage and surface peeling of rolling elements.

3. Multi-layer labyrinth high-temperature dense dust-proof composite sealing blocks ingress of ultra-fine carbon black and filler dust: Equipped with exclusive thickened wear lip & multi-labyrinth sealing structure for rubber & plastic conditions. It resists hardening and aging under high temperature and intercepts ultra-fine hard powder such as carbon black and calcium powder layer by layer, preventing dust penetration into cavities to contaminate grease and avoiding persistent abrasive wear induced by powder particles.

4. Deep-hardening super-finishing grinding technology for raceways reduces frictional temperature rise and suppresses vibration: Deep hardening treatment plus micron-level super-finishing grinding is applied on contact surfaces of raceways and rollers to optimize contact profile, improve oil film forming performance under high temperature, reduce accumulation of frictional heat, slow precision attenuation during long continuous operation, lower screw vibration and stabilize appearance and dimensional accuracy of extruded products.

5. Customized clearance for rubber & plastic conditions & high-temperature dust-resistant long-life lubrication system: Internal clearance is precisely matched according to different screw specifications and operating temperatures of extruders and pelletizers to avoid seizure under low temperature and thermal expansion seizure under sustained high temperature. Matched with special lubrication formula resistant to high temperature and powder contamination, it adapts to high-temperature dusty environments in rubber & plastic workshops and extends online lubrication maintenance intervals of equipment.

Application Scenarios

Screw support bearings for single & twin-screw extruders, traction roller and cutting roller support bearings for pelletizing units, transmission bearings for internal mixers, output end bearings for extrusion reduction gearboxes, heavy-duty transmission supporting positions of extrusion and pelletizing equipment on all plastic, rubber and modified material production lines.

Precision Quality Assurance

NMT tapered roller bearings for rubber & plastic extrusion pelletizing equipment are manufactured strictly in accordance with Japanese light heavy equipment manufacturing standards. Selected special bearing steel with heat resistance, high toughness and dense dust & wear resistance undergoes continuous high-temperature temperature rise test, ultra-fine powder sealing durability test, alternating load fatigue test, continuous heavy-load operation test and high-low temperature cycle aging test. The products feature outstanding bidirectional load capacity, excellent thermal stability and reliable long-term dust-proof sealing performance, fully adapting to 24-hour non-stop extrusion and pelletizing conditions with high temperature and ultra-fine filler dust in rubber & plastic workshops.

Product Range

Heavy-duty high-temperature resistant tapered roller bearings for extruder screws, long-life dust-proof bearings for pelletizing rollers, wear-resistant transmission bearings for internal mixers, low-vibration bearings for modified plastic production lines, customized large-size non-standard tapered roller bearings for large extrusion equipment.

Brand Strength

Japan NMT focuses on R&D and manufacturing of bearings for heavy rubber & plastic extrusion and pelletizing equipment under working conditions of continuous combined loads, high-temperature radiation from barrels, ultra-fine carbon black filler dust, screw axial thrust and uninterrupted continuous processing, specializing in core technologies of bidirectional load balance, high-temperature temperature rise control, dense dust-proof sealing protection and fatigue wear prevention. With Japanese heat-resistant high-toughness steel heat treatment technology, exclusive high-temperature dust-proof sealing technology for rubber & plastic equipment and strict high-temperature dust condition simulation testing system, it accurately solves industry pain points of extruder bearings such as high-temperature grease coking, abrasive wear failure by powder, fatigue spalling, frequent shutdown, cleaning and maintenance, supplying high-load, high-temperature resistant, dust and wear-resistant long-life core transmission bearing components for global rubber & plastic machinery manufacturers.