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What is a Double Row Cylindrical Roller Bearing?

Double row cylindrical roller bearings are separable bearings, allowing for easy assembly and disassembly. They feature a compact structure, high rigidity, and large load-bearing capacity with minimal deformation under load. Available in cylindrical bore or tapered bore (suffix K) designs, the tapered bore variant enables radial clearance adjustment during installation. These bearings can accommodate certain axial displacement between the shaft and housing, functioning as non-locating bearings.

Features of Double Row Cylindrical Roller Bearing

Double Row Cylindrical Roller Bearings have distinct structural and performance advantages that make them stand out in heavy-duty industrial applications, especially in rolling mill and heavy machinery fields. Their core features are as follows:

Superior Radial Load-Bearing Capacity: The double-row parallel roller design doubles the effective contact area between the rollers and the raceways compared to single-row cylindrical roller bearings. This structure enables the bearing to withstand extremely high radial loads (maximum radial load up to 2500 KN) and strong impact loads, which is perfectly adapted to the heavy-load working conditions of rolling mills, crushers, and other equipment.

High Rigidity and Stability: Adopting integral inner and outer rings (or separable inner/outer rings for easy installation) and high-precision roller sorting technology, the bearing has excellent structural rigidity. It can maintain minimal deformation under heavy loads, ensuring the stable operation of the host equipment and reducing vibration and noise during operation.

Excellent High-Speed Performance: The cylindrical rollers are in line contact with the raceways, and the optimized roller profile and cage structure reduce friction and heat generation during high-speed operation. The bearing can operate stably at a high speed of up to 5000 r/min (depending on the size and precision grade), meeting the high-speed requirements of motors, centrifuges, and other equipment.

Separable Structure for Easy Installation and Maintenance: Most models adopt a separable inner or outer ring structure, which allows the bearing to be disassembled and assembled separately during installation and maintenance, without removing the entire host equipment. This greatly simplifies the maintenance process, shortens the downtime, and reduces maintenance costs.

Wide Material and Cage Options: The inner and outer rings and rollers are mainly made of GCr15SiMn high-carbon chromium silicon manganese steel (standard material), which has high hardness, wear resistance, and fatigue resistance. For corrosive or high-temperature environments, SUS440C stainless steel or heat-resistant alloy materials can be selected. Cages are available in high-strength brass, phenolic resin, and integral steel cages, adapting to different working conditions such as high temperature, high speed, and heavy load.

High Precision and Long Service Life: Through precision grinding and strict quality control, the bearing can achieve precision grades of P5, P4, and even P2, ensuring high coaxiality and rotational accuracy. The optimized heat treatment process (quenching and tempering, sub-zero treatment) enhances the material performance, and the service life is extended by 30%-50% compared with ordinary single-row cylindrical roller bearings.

Applications of Double Row Cylindrical Roller Bearing

Due to its excellent heavy-load, high-rigidity, and high-speed performance, Double Row Cylindrical Roller Bearings are widely used in various heavy-duty industrial fields, especially in equipment that requires withstanding large radial loads and continuous stable operation. The main application fields are as follows:

Steel and Metallurgical Machinery: This is the most important application field of Double Row Cylindrical Roller Bearings. They are widely used in rolling mill work rolls, backup rolls, and reducer shafts. For example, hot rolling mills, cold rolling mills, and strip mills all rely on this type of bearing to withstand the huge radial pressure generated during the rolling process, ensuring the smooth progress of the rolling operation.

Motor and Generator Equipment: Applied to the main shafts of large and medium-sized motors, generators, and steam turbines. The bearing’s high radial load-bearing capacity and high-speed performance can adapt to the high-speed rotation of the motor shaft and the radial load generated by the rotor, ensuring stable power output and long-term reliable operation of the equipment.

Mining and Construction Machinery: Used in the main shafts of crushers, ball mills, bucket wheel excavators, and conveyor rollers. These equipment operate in harsh environments with heavy load, impact, and dust, and the Double Row Cylindrical Roller Bearing’s impact resistance and wear resistance can effectively extend the service life of the equipment and reduce maintenance frequency.

Heavy-Duty Gearboxes and Reducers: Integrated into the input and output shafts of heavy-duty gearboxes and reducers in metallurgy, mining, and construction fields. It can withstand the large radial load transmitted by the gears and ensure the stable operation of the transmission system with high precision and low noise.

Marine and Offshore Equipment: Applied to the main shafts of marine diesel engines, propellers, and offshore platform winches. The corrosion-resistant material option (SUS440C stainless steel) and sealed structure can adapt to the humid and corrosive marine environment, ensuring the reliability of marine equipment.

Other Heavy-Duty Equipment: It is also used in the main shafts of large precision machine tools, centrifuges, and hydraulic turbines, meeting the high-precision and heavy-load requirements of these equipment and providing reliable support for industrial production.

Factors Affecting the Price of Double Row Cylindrical Roller Bearing

The price of Double Row Cylindrical Roller Bearings is affected by multiple factors, mainly related to product size, material, precision, structure, order quantity, and customization requirements. The specific influencing factors are as follows:

Size and Load Rating: Size is one of the most important factors affecting the price. The larger the inner diameter (range: 50–1200 mm) and outer diameter (range: 80–1500 mm), the more raw materials (steel) are consumed, and the higher the processing difficulty (precision grinding, heat treatment). Bearings with ultra-high load ratings (above 1500 KN) require thicker raceways and larger rollers, which further increases production costs and prices.

Precision Grade: Precision grades are divided into P5, P4, and P2. High-precision bearings (P2/P4) need to go through more stringent grinding, testing, and sorting processes, and the rejection rate during production is higher. Therefore, their prices are 40%-70% higher than those of P5 grade bearings. High-precision bearings are mainly used in precision equipment such as large machine tools and generators, and the price difference is more obvious.

Material Selection: The standard material (GCr15SiMn) has a relatively low cost. If SUS440C stainless steel (corrosion-resistant) or heat-resistant alloy materials are selected, the raw material cost will increase by 50%-80%, and the price of the bearing will also increase accordingly. In addition, the material of the cage also affects the price: integral steel cages are more expensive than brass and phenolic resin cages.

Structural Complexity: Bearings with separable inner/outer rings are slightly more expensive than integral structure bearings due to higher processing requirements. If special structures are required, such as customized raceway profiles, lubrication holes, or shoulder specifications, additional processing steps will be added, and the price will increase by 30%-50% according to the complexity of the customization.

Sealing and Lubrication Configuration: Open-type bearings are the cheapest. If UU/U contact rubber seals, ZZ labyrinth seals, or other sealing structures are added, the processing and material costs will increase, and the price will be 15%-30% higher than that of open-type bearings. In addition, special lubrication solutions (such as high-temperature resistant grease) will also increase the overall cost.

Order Quantity and Delivery Time: Bulk orders (≥200 pieces) can enjoy a 15%-25% quantity discount, because mass production can reduce the unit processing cost and material waste. Small-batch orders (≤50 pieces) or urgent orders (delivery within 10 days) will incur additional scheduling, production, and logistics costs, and the unit price will increase by 20%-40%.

What Factors Should Be Considered When Purchasing Double Row Cylindrical Roller Bearing

Purchasing Double Row Cylindrical Roller Bearings requires comprehensive consideration of working conditions, product performance, cost-effectiveness, and supplier capabilities to ensure that the selected bearing can meet the actual operation needs of the equipment and achieve long-term stable operation. The key considerations are as follows:

Matching of Working Conditions: First, clarify the key working parameters of the equipment, including radial load, axial load (if any), rotational speed, working temperature, and environmental cleanliness. For example, rolling mill bearings need to select bearings with ultra-high radial load-bearing capacity and impact resistance; bearings used in corrosive environments need to be made of SUS440C stainless steel and equipped with sealed structures; high-speed equipment (such as motors) needs to select bearings with high-precision grades and optimized cages.

Confirmation of Size and Precision: Determine the inner diameter, outer diameter, and width of the bearing according to the equipment design drawings, and select the appropriate precision grade. For general heavy-duty equipment (such as crushers), P5 grade bearings can meet the requirements; for precision equipment (such as large machine tools and generators), P4/P2 high-precision bearings should be selected to ensure the positioning accuracy and operational stability of the equipment.

Selection of Materials and Cages: For general working conditions (room temperature, clean environment), GCr15SiMn material and brass cages are sufficient. For corrosive, high-temperature, or dusty environments, select SUS440C stainless steel, heat-resistant alloys, or integral steel cages. The selection of cages should also match the rotational speed: high-speed equipment is suitable for phenolic resin cages, while heavy-load equipment is suitable for brass or steel cages.

Assessment of Load Capacity: Calculate the static and dynamic radial loads of the equipment, and select bearings with load ratings higher than the actual working loads (usually 1.2–1.5 times the actual load) to ensure that the bearings can withstand impact loads and avoid premature damage due to overload. At the same time, pay attention to the limit speed of the bearing to ensure that it matches the rotational speed of the equipment.

Supplier Qualifications and After-Sales Service: Prioritize suppliers with professional production capacity and rich industry experience (such as NewBee Transmission). Verify the supplier’s production equipment (CNC precision grinding machines, load testing instruments), quality certifications (ISO9001), and product testing reports. In addition, understand the supplier’s after-sales service capabilities, such as warranty period, on-site installation guidance, and maintenance support, to avoid troubles in later use.

Balance of Cost-Effectiveness: Do not blindly pursue high precision and high-grade materials. Select products that match the actual working conditions according to the equipment’s importance and working requirements. For example, ordinary mining equipment does not need high-precision bearings, and selecting P5 grade bearings can reduce procurement costs. Domestic brands such as NewBee Transmission can replace imported brands (such as SKF, INA) with a cost advantage of 35%-50% and equivalent performance.

Supplier of Double Row Cylindrical Roller Bearing

NewBee Transmission is a professional supplier of high-quality Double Row Cylindrical Roller Bearings, focusing on providing reliable heavy-load bearing solutions for global customers in steel, metallurgy, mining, motor, and other industries. With advanced production technology, strict quality control, and professional service capabilities, NewBee Transmission has become a trusted partner of many large industrial enterprises.

Comprehensive Product Range: The standard Double Row Cylindrical Roller Bearing series covers inner diameters of 50–1200 mm, outer diameters of 80–1500 mm, and widths of 20–300 mm, with precision grades from P5 to P2. It provides open-type, UU/U sealed-type, and ZZ labyrinth sealed-type options, and supports non-standard customization of size, material, and structure to meet the diverse needs of different industries.

Advanced Manufacturing and Testing Capabilities: The company adopts international advanced CNC precision grinding machines, integral heat treatment lines, and roller sorting equipment, and implements strict quality control throughout the production process. From raw material inspection (spectral analysis, metallographic detection) to finished product testing (load capacity, precision, noise, fatigue life), 100% inspection is carried out to ensure product consistency and reliability. The company’s testing center is equipped with professional load testing instruments and high-precision measuring equipment, which can fully meet the testing requirements of high-precision bearings.

Professional Customization Services: NewBee Transmission has a team of senior engineers with more than 15 years of experience in bearing design and manufacturing, who can provide one-stop customization solutions according to customers’ specific working conditions and equipment requirements. Whether it is non-standard size design, material modification (corrosion-resistant, high-temperature resistant), or special structure customization (lubrication holes, shoulder specifications), the company can complete the design, sample development, and mass production efficiently, with a sample development cycle of only 15–20 days.

Reliable Quality Assurance and After-Sales Service: All products comply with ISO9001 quality management system standards and national bearing industry standards, with a product warranty period of 1.5 years. The company has a perfect after-sales service system, providing 24-hour technical consultation, on-site installation guidance, and maintenance training. For quality problems caused by product itself, the company implements free replacement and maintenance to ensure that customers’ production is not affected.

High Cost-Effectiveness and Efficient Logistics: Relying on localized production and optimized supply chain management, NewBee Transmission’s Double Row Cylindrical Roller Bearings are 35%-50% cheaper than imported brands, while ensuring the same or higher performance. The company has an intelligent warehousing center, and the delivery cycle of standard models is 7–15 days; for customized models, the delivery cycle is 8–14 weeks. It cooperates with international logistics companies (DHL, FedEx) and has overseas warehouses in Europe and North America, realizing fast delivery to global customers.

Precautions for Using Double Row Cylindrical Roller Bearing

Double Row Cylindrical Roller Bearings are mainly used in heavy-load, high-speed, and harsh working environments. Correct installation, lubrication, and maintenance are crucial to extending their service life and ensuring the stable operation of the equipment. The key precautions are as follows:

Standardized Installation Operation: Before installation, thoroughly clean the bearing, shaft, and housing bore to remove burrs, oil stains, and impurities, which can avoid wear of the raceway and rollers. Use special pressing tools for assembly, apply force evenly on the inner or outer ring (according to the separable structure), and prohibit hammering or knocking, which will cause deformation of the raceway, damage to the rollers, and affect the bearing’s performance. After installation, check the coaxiality and axial clearance of the bearing to ensure that they meet the design requirements; for bearings that require preload, adjust the preload accurately according to the specifications.

Scientific Lubrication Maintenance: Select appropriate lubricating grease or oil according to the working temperature, rotational speed, and load. For high-temperature environments (above 80°C), use high-temperature resistant grease; for high-speed equipment, use low-viscosity lubricating oil. Open-type bearings need regular lubrication, and the lubricating grease should be replaced every 1000–2000 working hours; sealed bearings should be checked regularly for grease leakage, and if leakage is found, replace the seal and add lubricating grease in time. Avoid excessive or insufficient lubrication: excessive lubrication will increase friction and heat generation, while insufficient lubrication will cause dry friction and damage the bearing.

Real-Time Operation Monitoring: During the operation of the equipment, monitor the temperature, vibration, and noise of the bearing in real time. The normal operating temperature of the bearing should be within 30–80°C, and the temperature rise should not exceed 18°C. If the temperature is too high, it may indicate insufficient lubrication, installation misalignment, or overload, and the equipment should be shut down for inspection immediately. Abnormal vibration or noise may signal wear of the rollers or raceway, damage to the cage, or foreign matter entering the bearing, which requires timely disassembly and inspection.

Proper Storage and Handling: Store the bearing in a clean, dry, and ventilated environment with a humidity of ≤60%, and avoid direct contact with acids, alkalis, and other corrosive substances to prevent rust. The bearing should be placed horizontally, and avoid stacking heavy objects on it to prevent deformation of the inner and outer rings. When transporting the bearing, use shockproof packaging (such as foam, carton with shockproof cotton) to avoid collision, falling, or vibration, which will damage the bearing’s precision and structure.

Regular Inspection and Maintenance: Regularly disassemble and inspect the bearing according to the equipment’s operation cycle. Check the wear of the raceway and rollers, the integrity of the cage, and the condition of the seal. If wear, deformation, or damage is found, replace the bearing in time to avoid equipment failure caused by bearing damage. After disassembly, clean the bearing thoroughly, apply new lubricating grease, and reinstall it correctly.

For technical specifications, pricing, or custom engineering solutions:

Email: paul@newbeetrans.com

Website: www.newbeetrans.com