Dryer cylinders, press rolls, size press rolls and winders are core equipment of paper production lines. Bearing housings for dryers and support positions of press rolls operate under harsh working conditions: ultra-large continuous combined squeezing loads, high-temperature heat conducted from dryer cylinders, high humidity vapor surrounding workshops, massive floating fine paper dust generated during production, periodic axial force produced by roll surface extrusion and non-stop all-weather continuous papermaking. Paper production lines demand extremely high continuity. Once the paper machine shuts down and restarts, paper breakage and difficult threading easily occur, a large amount of wet web will be scrapped, and it takes a long time to restore normal production, directly causing considerable economic losses. Ordinary tapered roller bearings cannot adapt to harsh high-temperature high-humidity and dust-filled environments in paper mills, becoming a common pain point for paper machinery manufacturers and paper mill maintenance teams. During operation, press rolls continuously bear huge squeezing pressure and periodic alternating loads, and loads fluctuate with web thickness and moisture content. Ordinary bearings have insufficient fatigue resistance and tend to form raceway indentation and rolling element surface peeling under long-term cyclic loads, triggering roll runout, which leads to paper wrinkling, breakage and uneven thickness. Dryer cylinders continuously radiate high temperature outward, raising ambient temperature around bearings. Conventional grease easily oxidizes, hydrolyzes and cokes under high temperature, resulting in abnormal temperature rise of bearings. The production area is filled with fine wood-based paper dust with abrasive properties. Simple seals cannot provide effective barrier. Paper dust penetrates along water vapor into bearing housings, mixes with grease and forms persistent abrasive medium that continuously wears raceways and rolling elements. High-temperature water vapor easily penetrates seal gaps, emulsifies grease and induces internal rust of bearings. Alternating hot and cold conditions in dryer sections continuously accelerate seal aging and damage. Disassembly and assembly of large paper machines are complicated, and shutdown for bearing maintenance greatly reduces effective production hours and continuously increases paper mill operation costs.

Focusing on transmission supporting field for paper making equipment, Japan NMT specially develops high-temperature moisture & paper dust resistant tapered roller bearings dedicated for press sections and dryer sections of paper machines to solve industry pain points of ordinary paper machine bearings such as insufficient heat resistance, easy water vapor ingress causing grease emulsification, abrasive wear induced by fine paper dust, fatigue damage under squeezing loads and limited service life under continuous papermaking 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 moisture & paper dust-proof composite sealing, deep-hardening super-finishing technology for raceways, high-temperature hydrolysis resistant long-life lubrication and precise clearance matching for papermaking working conditions, it fully adapts to harsh conditions of dryer cylinders and press rolls with high-temperature radiation, high humidity vapor and paper dust interference. It fundamentally solves problems including high-temperature grease coking, rust caused by water vapor, abrasive wear by paper dust and grease emulsification, stabilizes rotation precision of all kinds of rolls and guarantees long-cycle continuous papermaking operations of paper production lines.

Core Product Advantages

1. Bidirectional ultra-large combined load bearing withstands roll squeezing pressure and dynamic axial thrust: Adopting tapered roller linear contact structure, it bears high-strength radial squeezing loads and continuous axial thrust simultaneously with uniform load distribution in contact zones. It buffers load impact caused by web fluctuation, restrains excessive unilateral raceway wear induced by eccentric load of press rolls and dryers, stably controls axial play of shaft systems, ensures smooth web running and reduces defects such as paper breakage and wrinkles.

2. Heat-resistant high-toughness bearing steel matrix delivers long-term fatigue and corrosion resistance under high temperature and humidity: Selected high-purity heat-resistant bearing alloy steel specially for heavy paper making equipment undergoes deep quenching & tempering heat treatments to optimize metallographic structure under high temperature and humidity, improve matrix toughness, compressive strength and vapor corrosion resistance under thermal conditions. It withstands long-term alternating squeezing loads of rolls, delays raceway fatigue damage and surface peeling of rolling elements, and lowers risks of pitting corrosion induced by water vapor.

3. Multi-layer labyrinth high-temperature moisture & paper dust-proof composite sealing blocks ingress of water vapor and fine paper dust: Equipped with exclusive thickened moisture-resistant wear lip & multi-labyrinth sealing structure for papermaking conditions. It resists hardening and aging under high temperature and humidity, intercepts high-temperature vapor and fine paper dust layer by layer, prevents vapor and paper dust from entering housings and contaminating grease, and avoids persistent abrasive wear and grease emulsification failure caused by paper dust.

4. Deep-hardening super-finishing grinding technology for raceways reduces frictional temperature rise and suppresses roll system 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 high-temperature humid conditions, reduce accumulation of frictional heat, slow precision attenuation during long continuous operation, lower roll vibration and stabilize paper surface quality and width accuracy.

5. Customized clearance for papermaking conditions & high-temperature hydrolysis resistant long-life lubrication system: Internal clearance is precisely matched according to different operating temperature and squeezing load of dryer cylinders and press rolls to avoid seizure under low temperature and thermal expansion seizure under sustained high temperature. Matched with special lubrication formula resistant to high temperature, vapor hydrolysis and paper dust contamination, it adapts to high-temperature and high-humidity environments in paper mills and extends online lubrication maintenance intervals of bearings.

Application Scenarios

End support bearings for paper machine dryer cylinders, bearing housing bearings for upper and lower press rolls, support bearings for size press rolls and calender rolls, transmission bearings for winders, heavy-duty transmission supporting positions of pressing and drying sections on all cultural paper, packaging paper and tissue paper production lines.

Precision Quality Assurance

NMT tapered roller bearings for paper making machinery are manufactured strictly in accordance with Japanese light heavy equipment component manufacturing standards. Selected special bearing steel with heat resistance, high toughness, moisture resistance and paper dust abrasion resistance undergoes continuous high-temperature temperature rise test, humid heat cycle sealing durability test, paper dust flushing wear test, alternating squeezing load fatigue test and high-low temperature humid cycle aging test. The products feature outstanding bidirectional load capacity, excellent thermal and moisture stability and reliable long-term vapor & dust-proof sealing performance, fully adapting to 24-hour non-stop papermaking conditions with high temperature, high humidity and floating paper dust in paper workshops.

Product Range

Heavy-duty high-temperature resistant tapered roller bearings for dryer cylinders, long-life moisture & paper dust resistant bearings for press rolls, wear-resistant transmission bearings for calender rolls, low-vibration bearings for winders, customized large-size non-standard tapered roller bearings for complete large paper making equipment.

Brand Strength

Japan NMT focuses on R&D and manufacturing of bearings for heavy papermaking drying equipment under working conditions of continuous combined squeezing loads, high-temperature radiation from dryers, high humidity vapor in workshops, floating fine paper dust and uninterrupted continuous papermaking, specializing in core technologies of bidirectional load balance, high-temperature temperature rise control, vapor-proof dense sealing protection and fatigue wear prevention. With Japanese heat treatment technology for heat-resistant high-toughness steel, exclusive high-temperature and moisture resistant sealing technology for paper machinery and strict high-temperature humid condition simulation testing system, it accurately solves industry pain points of main paper machine bearings such as high-temperature grease coking, rust caused by vapor emulsification, abrasive wear failure by paper dust and frequent shutdown for paper threading and maintenance, supplying high-load, high-temperature resistant, vapor and paper dust-proof long-life core transmission bearing components for global paper machinery manufacturers.