Sinter strands, annular coolers and apron feeders are core equipment for metallurgical sintering processes. Pallet travelling wheels, sprocket supports of sinter machines, slewing supports and roller table transmissions of annular coolers operate under harsh working conditions: continuous combined heavy loads, baking radiation from high-temperature flue gas, hard dust generated by sinter, thermal shock from alternating hot and cold cycles, low-speed continuous operation and non-stop all-weather sintering production. As a key front-end procedure for iron and steel smelting, sintering lines demand extremely high continuity. Once bearing failure causes shutdown, the whole sintering chain will stall. High-temperature sinter cannot be cooled and transported, materials pile up and agglomerate, and reheating for restart takes a long time. It directly leads to interruption of raw material supply for ironmaking, triggering output fluctuation and substantial economic losses across the whole process. Ordinary tapered roller bearings cannot adapt to harsh high-temperature, thermal cycling and dust-filled environments in sintering workshops, becoming a common pain point for metallurgical equipment manufacturers and steel plant maintenance teams. During operation, sinter pallets and annular coolers continuously bear fluctuating reciprocating loads and axial forces, and frequent periodic impact occurs during start-stop and direction switching. Ordinary bearings lack sufficient thermal fatigue resistance and tend to form raceway indentation and rolling element surface peeling under long-term cyclic temperature and load variation, resulting in pallet jamming and abnormal operation noise. Sintering areas are exposed to high flue gas temperature; bearings are continuously heated by thermal radiation. Conventional grease easily oxidizes and carbonizes under high temperature, leading to excessive temperature rise and seizure of bearings. Sinter dust features high hardness and sharp edges. Simple seals are easily scratched and worn by hard particles. Dust continuously penetrates into bearing housings, mixes with grease and forms abrasive medium that continuously wears raceways and rolling elements. Alternating operation between high-temperature zones and cooling zones subjects sealing materials to drastic temperature shocks repeatedly, accelerating hardening, cracking and loss of protection. Disassembly of complete large sintering equipment is complicated, and shutdown for bearing maintenance greatly shortens effective sintering hours and continuously increases steel plant operation costs.

Focusing on transmission supporting field for metallurgical sintering equipment, Japan NMT specially develops high-temperature dust-proof heavy-duty tapered roller bearings dedicated for sinter strands and annular coolers for metallurgical sintering lines to solve industry pain points of ordinary sintering bearings such as insufficient heat resistance, susceptibility to thermal fatigue under alternating hot and cold conditions, abrasive wear induced by sinter dust, high-temperature lubrication failure and limited service life under continuous sintering operation. Taking advantage of bidirectional linear load-bearing structure of tapered rollers, combined with five core upgrades including heat-resistant thermally stable bearing alloy steel, multi-layer labyrinth high-temperature sinter dust-proof composite sealing, deep-hardening super-finishing strengthening technology for raceways, high-temperature anti-dust long-life lubrication and precise clearance matching for low-speed heavy sintering conditions, it fully adapts to harsh sintering line conditions with high-temperature radiation, alternating thermal shock and hard sinter dust interference. It fundamentally solves problems including high-temperature grease coking, abrasive wear by dust, thermal cycling fatigue spalling and lubrication failure, stabilizes rotation precision of pallets and slewing mechanisms and guarantees long-cycle continuous stable production of metallurgical sintering lines.

Core Product Advantages

1. Bidirectional ultra-large combined load bearing withstands continuous heavy loads and periodic axial impact: Adopting tapered roller linear contact structure, it bears high-strength continuous radial heavy loads and continuous axial thrust simultaneously with uniform load distribution in contact zones. It effectively buffers alternating impact generated during pallet start-stop and direction switching, balances eccentric loads during equipment operation, restrains local overload wear on unilateral raceways and stably controls axial play of shaft systems to ensure smooth operation of sinter pallets and annular coolers and reduce jamming failures.

2. Heat-resistant thermally stable bearing steel matrix delivers long-term thermal fatigue and wear resistance under alternating hot and cold conditions: Selected high-purity thermally stable bearing alloy steel specially for metallurgical sintering equipment undergoes multiple quenching & tempering heat treatments to optimize metallographic structure in wide temperature range, improve high-temperature toughness and thermal cycle fatigue resistance. It withstands long-term reciprocating loads under sintering conditions, delays raceway fatigue damage and surface peeling of rolling elements, and lowers risks of surface cracks induced by temperature alternation.

3. Multi-layer labyrinth high-temperature sinter dust-proof composite sealing blocks continuous ingress of hard sinter dust: Equipped with exclusive thickened wear-resistant seal lip & multi-labyrinth protective structure for sintering conditions. It resists alternating high-low temperature thermal shock and is not easily scratched and damaged by sharp sinter dust particles. It intercepts sinter dust and particulate matter carried by flue gas layer by layer, prevents hard dust from entering housings and contaminating grease, and avoids persistent abrasive wear induced by sinter dust.

4. Deep-hardening super-finishing grinding technology for raceways controls frictional temperature rise and suppresses operation 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 stability under alternating hot and cold conditions, reduce heat accumulation under low-speed heavy loads, slow precision attenuation after years of continuous operation and lower vibration and abnormal noise of main sintering equipment.

5. Customized clearance for low-speed heavy sintering conditions & high-temperature anti-dust long-life lubrication system: Internal clearance is precisely matched according to different operating temperature and load of sinter pallet wheels, sprockets and annular cooler slewing supports to avoid seizure under low temperature and thermal expansion seizure under sustained high temperature. Matched with special lubrication formula resistant to high temperature and impurity contamination, it adapts to alternating hot and cold high-temperature environments in sintering workshops and extends online lubrication maintenance intervals of equipment.

Application Scenarios

Travelling wheel bearings for sinter pallets, support bearings for head and tail sprockets, slewing support and roller table transmission bearings for annular coolers, transmission bearings for apron feeders, heavy-duty low-speed transmission supporting positions of all iron ore sintering and pellet sintering production lines.

Precision Quality Assurance

NMT tapered roller bearings for metallurgical sintering equipment are manufactured strictly in accordance with Japanese heavy metallurgical sintering equipment component manufacturing standards. Selected special bearing steel with heat resistance, thermal stability and dust abrasion resistance undergoes continuous high-temperature temperature rise test, alternating hot-cold thermal fatigue test, sinter dust flushing sealing durability test, alternating load fatigue test and long-duration low-speed heavy-load operation test. The products feature powerful bidirectional load capacity, outstanding thermal stability and robust reliable dust-proof sealing performance, fully adapting to 24-hour non-stop sintering conditions with high-temperature flue gas, thermal cycling and hard dust in sintering workshops.

Product Range

Heavy-duty high-temperature resistant tapered roller bearings for sinter pallets, long-life dust-proof bearings for annular cooler slewing systems, thermal fatigue resistant bearings for sprocket supports, wear-resistant transmission bearings for apron feeders, customized large-size non-standard tapered roller bearings for complete large sintering equipment.

Brand Strength

Japan NMT focuses on R&D and manufacturing of bearings for heavy metallurgical sintering equipment under working conditions of continuous combined heavy loads, high-temperature flue gas radiation, alternating hot-cold thermal shock, erosion by hard sinter dust and low-speed non-stop continuous sintering, specializing in core technologies of bidirectional load balance optimization, high-temperature thermal stability control, multi-layer high-temperature dust-proof sealing protection and thermal cycling fatigue wear prevention. With Japanese heat treatment technology for heat-resistant thermally stable steel, exclusive high-temperature dust-proof sealing technology for sintering machinery and strict sintering condition simulation durability testing system, it accurately solves industry pain points of sintering bearings such as high-temperature grease coking, abrasive wear failure by dust, thermal fatigue spalling under temperature alternation and raw material agglomeration & output interruption caused by shutdown, supplying high-load, high-temperature resistant, thermal fatigue & dust-proof long-life core transmission bearing components for global metallurgical sintering machinery manufacturers.