I. About NMT

Japan NMT is a brand dedicated to the R&D and manufacturing of precision bearings. The product portfolio covers deep groove ball bearings, angular contact ball bearings, cylindrical roller bearings, spherical roller bearings, self-aligning ball bearings, thrust ball bearings, crossed roller bearings, thin-section bearings, cylindrical thrust roller bearings, mounted spherical plain bearings, spherical plain bearings, split bearings and other full-series products. Guided by the core philosophy of "systematic precision engineering," NMT integrates advanced technologies in materials science, precision machining and tribology into the design and manufacturing of various bearing types, widely applied in metallurgical equipment, paper machinery, cement equipment, mining machinery and large slewing supports.

II. Product Introduction

Heavy rotating equipment such as metallurgical rotary kilns, paper machine dryer cylinders, cement equipment large roller presses, mining ball mills and large fans often have bearings installed in the middle of shafts, with couplings, gears or large components blocking both sides, making it impossible to install or remove bearings from the shaft ends. Traditional solid bearings require complete disassembly of the shaft system or extracting the entire shaft during installation and maintenance, resulting in massive workload, long downtime and high maintenance costs. When bearings wear out and need replacement during long-term continuous operation, traditional methods often require days or even weeks of downtime, causing enormous production losses.

Most heavy continuous-operation equipment requires bearings with split structures to enable installation, inspection and replacement without moving the shaft system or disassembling components on both sides. Equipment maintenance windows are limited, requiring fast and efficient bearing replacement operations. The industry urgently requires bearing products that can be split radially, offer convenient installation and removal, provide reliable load capacity and suit large heavy-duty equipment.

NMT Split Bearings adopt a structural design where the bearing housing, shaft sleeve and rolling element assembly are split into two halves along the radial direction. The upper half can be independently lifted and separated while the lower half remains in place, enabling bearing installation and removal without moving the shaft system. Inner rings, outer rings, rolling elements and cages are all split into two halves along the diameter. Split faces are precision-machined and connected by high-strength bolts after closure to restore a complete bearing structure. The split faces feature precise locating structures to ensure roundness and coaxiality of inner and outer rings meet design requirements after closure. Cages are also designed as split structures to ensure even rolling element distribution at the split faces.

NMT split bearings require no heating, no hydraulic equipment during installation and removal, only conventional lifting tools and wrenches, significantly reducing equipment downtime. Products are available in multiple structural types——split cylindrical roller bearings, split spherical roller bearings, split deep groove ball bearings——adapting to different load types and operating conditions. Rolling elements are precision-machined from high-purity bearing alloy steel. Rings undergo forging, precision grinding and superfinishing. All components receive quenching heat treatment and long-term low-temperature stabilization processing, with split faces precision-ground to ensure closure accuracy. Products adopt international standard dimensions with interchangeability with solid bearings of the same specification.

Core Product Advantages

1. Bearings split radially into two halves enable installation and removal without moving the shaft system, significantly reducing equipment downtime;

2. Precision-machined split faces with locating design restore complete bearing structure after closure, with roundness and coaxiality meeting design requirements;

3. Installation and removal require no heating, no hydraulic equipment, only conventional lifting tools and wrenches for convenient operation;

4. Multiple structural types available (split cylindrical roller, split spherical roller, split deep groove ball) adapting to different load types and operating conditions;

5. Precision heat treatment across all components provides high surface hardness, good wear resistance and reliable load capacity;

6. Split cage design ensures even rolling element distribution at split faces for smooth operation;

7. Particularly suitable for applications where bearings are installed in the middle of shafts with both sides blocked, preventing shaft-end operation;

8. Standard external dimensions ensure interchangeability with solid bearings of the same specification, convenient replacement and reduced spare parts inventory pressure.

Typical Application Scenarios

Metallurgical rotary kiln supports and transmission devices; Paper machine dryer cylinder bearings and press roll bearings; Cement equipment roller presses and large vertical mills; Mining ball mills and rotary crushers; Large fans and ventilation equipment; Marine propulsion system intermediate bearings; Large conveyor drum bearings; Port machinery and crane slewing supports.

Quality Assurance

NMT Split Bearings are manufactured with premium refined bearing alloy steel. Incoming inspection includes chemical composition testing and metallurgical sampling inspection to eliminate material defects at source. Stress relief annealing is conducted after rough machining of ring forgings to eliminate internal stress, followed by quenching heat treatment and low-temperature stabilization treatment to ensure dimensional stability under long-term heavy loads. Split faces undergo precision milling and grinding with strict control over flatness and surface roughness to ensure fit accuracy after closure. Split face locating structures are precision-machined to ensure roundness and coaxiality of inner and outer rings meet design requirements after closure. Cages are precision-machined and split into two halves with precise split face配合 to ensure even rolling element distribution.

All components go through high-pressure cleaning and dust-free drying before assembly in clean workshops. During assembly, split faces are coated with rust-preventive lubricant and high-strength bolts are tightened to specified torque. After assembly, finished bearings undergo radial load endurance testing, split face closure accuracy inspection, rotational accuracy inspection and vibration testing. All unqualified products are eliminated completely to guarantee stable and consistent performance of bulk goods and supply reliable split bearing solutions for large heavy-duty equipment.

Product Range

Split bearing standard series (split cylindrical roller bearings, split spherical roller bearings, split deep groove ball bearings); Split bearing housings; Bore diameters from 50mm to over 600mm.

Brand Strength

Japan NMT focuses on R&D and manufacturing of precision split bearings. Targeting common industry challenges of difficult installation in middle-shaft positions, long maintenance downtime and massive workload of traditional solid bearing replacement in metallurgy, paper, cement and mining industries, NMT continuously optimizes split structure design, split face machining processes and heat treatment technology. NMT split bearings, with convenient installation without moving shaft systems, reliable load capacity and long service life, effectively solve common problems of traditional solid bearings such as inability to install in confined spaces and long maintenance cycles. NMT products significantly shorten equipment maintenance downtime, improve production line operating efficiency, and support stable continuous operation of various large heavy-duty equipment.