Cylindrical Roller Bearing CBK238 FONKIN

The FONKIN CBK238 is a high-performance single-row cylindrical roller bearing, designed for heavy radial loads and moderate-speed industrial applications. It complies fully with ISO 355 and DIN 628 standards, featuring a compact structure, reliable load-bearing capacity and cost-effectiveness, which makes it widely used in general industrial fields. As a cost-efficient bearing solution, it is characterized by stable performance and easy installation, distinguishing itself from high-end precision bearings with its practicality and adaptability to common working conditions.

1. Detailed Dimensional Parameters: Conforming to ISO 355 and DIN 628 standards, the bearing has an inner diameter (d) of 50mm, outer diameter (D) of 80mm, and width (B) of 15mm. The minimum chamfer size (rₘᵢₙ) is 1.0mm, single weight is 0.28kg. Its tolerance grade is P0 (ISO 492), with inner/outer diameter tolerance of IT6 and width tolerance of IT7. The basic dynamic load rating is 48kN, basic static load rating is 45kN, reference speed (grease lubrication) is 6500r/min, and limiting speed (oil lubrication) is 9000r/min. It adopts a cylindrical bore with normal radial internal clearance (CN), adapting to general industrial operating conditions.

2. Specific Material Description: Inner ring, outer ring and cylindrical rollers are made of high-carbon chromium bearing steel (AISI 52100/SUJ2), refined by vacuum degassing technology to reduce harmful impurities. After precision heat treatment, it reaches a hardness of 60-64 HRC, featuring excellent wear resistance, high fatigue strength and stable dimensional accuracy under long-term cyclic loading. The retainer is made of high-strength steel (suffix S), which has good impact resistance and wear resistance, ensuring stable roller guidance and reducing friction at medium to high speeds, suitable for heavy-load working scenarios.

3. Core Processing Technology: Key manufacturing processes follow FONKIN’s strict quality standards: closed-die forging, CNC turning, controlled atmosphere heat treatment, precision grinding and superfinishing. Closed-die forging ensures dense internal structure and continuous metal fiber distribution, enhancing load-bearing capacity. CNC turning achieves Ra ≤ 0.4μm surface roughness, ensuring precise dimensional control. Heat treatment adopts nitrogen-hydrogen protective atmosphere to avoid oxidation and decarburization, ensuring uniform hardness distribution. Precision grinding with CBN砂轮 and superfinishing reduce raceway roughness to Ra ≤ 0.05μm, minimizing friction and extending service life.

4. Service Life: Under standard working conditions (3000r/min, radial load 18kN, proper lubrication and clean environment), the L₁₀ basic rated life (90% reliability) is 25,000 operating hours, calculated in accordance with ISO 281:2007 standard. Key influencing factors include lubrication quality, pollution level, installation accuracy and load magnitude; insufficient lubrication or excessive contamination can reduce service life by 30-50%, while overload operation may cause premature bearing damage.

5. Application Scenarios and Industries: Widely used in general mechanical manufacturing, automotive accessories, trailer parts, agricultural machinery and light industrial equipment industries. Typical applications include trailer suspensions, small gearboxes, agricultural machinery transmissions, conveyor systems and electric motor supports. It is suitable for these scenarios due to its compact structure, high radial load capacity, cost-effectiveness and stable performance, adapting to heavy-load, moderate-speed and low-maintenance operating conditions.

6. Basic Maintenance Requirements: Maintenance cycle is 1800 operating hours. Lubrication: Use lithium-based grease (NLGI 2) or extreme pressure gear oil (ISO VG 68), filling amount 15-25% of the bearing’s free space; re-lubricate every 1200-1800 hours. Cleaning: Remove dust and old grease with clean kerosene; avoid corrosive cleaners and ensure thorough drying after cleaning. Regular inspection: Check for abnormal noise, temperature rise and grease leakage; replace lubricant immediately if it darkens or deteriorates, and inspect for roller or raceway wear if vibration increases.

7. Installation Precautions: Pre-installation: Keep the installation area clean; remove burrs from the shaft and housing, and verify dimensional accuracy. Do not open the bearing package until installation to prevent contamination. Installation: Apply a thin oil film to fitting surfaces; use a press to apply force evenly to the inner ring (avoid hammering to prevent damage). Ensure coaxiality tolerance ≤ 0.02mm. Fastening torque: Tighten housing bolts to 80-100N·m in a diagonal sequence. Post-installation: Rotate the bearing manually to check for jamming; measure operating temperature after 30 minutes (normal ≤ 70℃). Safety: Wear protective gloves and goggles; use specialized lifting tools for handling, and avoid direct contact with raceways to prevent surface damage.