Angular Contact Ball Bearing Double Row 3319A-2Z/C3 SKF

The SKF 3319A-2Z/C3 is a high-performance double-row angular contact ball bearing, featuring a 30° contact angle (suffix A), two-sided metal shields (suffix 2Z) and increased radial internal clearance (suffix C3). It fully complies with ISO 355 and DIN 628 standards, integrating high load-bearing capacity, good rigidity and reliable sealing performance. Its unique design is tailored for applications requiring combined radial and axial loads, distinguishing itself with excellent high-speed stability and adaptability to thermal expansion, making it ideal for heavy-duty industrial scenarios.

1. Detailed Dimensional Parameters: Conforming to international bearing standards, the bearing has an inner diameter (d) of 95mm, outer diameter (D) of 200mm, and width (B) of 77.8mm. The minimum chamfer size (rₘᵢₙ) is 2.5mm, single weight is 5.8kg. 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 195kN, basic static load rating is 228kN, reference speed (grease lubrication) is 3200r/min, and limiting speed (oil lubrication) is 4500r/min. The C3 internal clearance (0.065-0.110mm) accommodates thermal expansion in high-temperature operations.

2. Specific Material Description: Inner ring, outer ring and ball rolling elements are made of high-carbon chromium bearing steel (AISI 52100/SUJ2), refined by vacuum degassing technology to reduce non-metallic inclusions. After precision heat treatment, it reaches a hardness of 61-65 HRC, featuring excellent wear resistance, high fatigue strength and stable dimensional accuracy under cyclic loading. The retainer is made of brass (H62), with good thermal conductivity and impact resistance, ensuring stable ball guidance. The 2Z metal shields are made of carbon steel (SPCEN), providing effective dust protection without compromising rotational flexibility.

3. Core Processing Technology: Key processes follow SKF’s stringent standards: closed-die forging, CNC turning, controlled atmosphere heat treatment, precision grinding and superfinishing. Closed-die forging ensures dense internal structure and continuous metal fibers. CNC turning achieves Ra ≤ 0.3μm surface roughness. Heat treatment adopts nitrogen-hydrogen atmosphere to avoid oxidation and decarburization. Precision grinding with CBN砂轮 and superfinishing reduce raceway roughness to Ra ≤ 0.04μm, minimizing friction. The 30° contact angle is precision machined to optimize load distribution, and metal shields are tightly fitted to ensure sealing performance.

4. Service Life: Under standard working conditions (2800r/min, radial load 65kN, proper lubrication and clean environment), the L₁₀ basic rated life (90% reliability) is 18,000 operating hours, calculated in accordance with ISO 281:2007 standard. Key influencing factors include lubrication quality, contamination level, installation accuracy and load magnitude; insufficient lubrication or excessive contamination can reduce service life by 30-50%.

5. Application Scenarios and Industries: Widely used in machinery manufacturing, automotive, engineering machinery, textile and printing industries. Typical applications include large electric motors, gearboxes, rolling mills, centrifugal pumps and plastic packaging machinery. It is suitable for these scenarios due to its double-row structure (high load capacity), 30° contact angle (combined radial-axial load adaptability), C3 clearance (thermal expansion adaptability) and 2Z shields (dust protection).

6. Basic Maintenance Requirements: Maintenance cycle is 2000 operating hours. Lubrication: Lithium-based grease (NLGI 2) or extreme pressure gear oil (ISO VG 68), filling amount 15-30% of bearing free space; re-lubricate every 1500-2000 hours. Cleaning: Clean surface and shields with clean kerosene; avoid corrosive cleaners. Regular inspection: Check for abnormal noise, temperature rise and grease leakage; replace lubricant if deteriorated.

7. Installation Precautions: Pre-installation: Keep area clean, remove burrs from shaft/housing, check fitting surface roughness (Ra ≤ 0.8μm). Installation: Apply thin oil film, press evenly on inner ring (no tapping), ensure coaxiality tolerance ≤ 0.02mm. Fastening torque: 140-170N·m for bearing seat bolts. Post-installation: Rotate manually to check jamming; measure temperature after 30 minutes (normal ≤ 72℃). Safety: Wear protective gloves/goggles, use specialized lifting tools.