Cylindrical Roller Bearings from China Suppliers: Quality Factory Direct Options for Your Needs

High-precision single-row cylindrical roller bearings with a 1:12 tapered bore for machine tool spindles are also produced.

Double-row cylindrical roller bearings are manufactured as precision-grade bearings for machine tool spindles and can also be used in other precision machinery.

To facilitate the installation of lubrication devices, bearings with oil grooves and holes on the outer ring (suffix code W33) are primarily supplied. Products with either cylindrical or tapered bores are available based on customer requirements.

The basic dimensions of the bearings listed in the tables comply with ISO 15:1981.

Proper adjustment of the contact condition between the rollers and raceways not only prevents abnormal loading on the contact surfaces but also accommodates misalignment between the inner and outer rings caused by installation errors. The permitted tilt angles for cylindrical roller bearings are as follows:

Single-row cylindrical roller bearings are produced with tolerances up to P5 grade. Additionally, single-row and double-row cylindrical roller bearings with tapered bores for machine tool spindles are manufactured with P5 grade and higher tolerances, as well as special tolerance classes SP and UP.

Standard single-row cylindrical roller bearings are supplied with basic group clearance. Single-row bearings can also be provided with C3 group clearance, and some sizes are available with C4 group clearance.

Double-row cylindrical roller bearings are supplied with C1 group clearance as standard. Bearings with cylindrical bores can also be supplied with C2 or C3 group clearance, while tapered bore bearings can be provided with C2 group clearance.

The standard cages for single-row cylindrical roller bearings are listed in the table below. Cages for NU, NJ, NF, and NUP-type bearings are typically the same as those for N-type bearings.

To prevent harmful sliding between the rollers and raceways due to centrifugal forces during high-speed operation, the minimum required load for the bearing can be estimated using the following formula:

Where:

• F_r — Minimum radial load (N)
• K_r — Minimum load coefficient:
  • = 100 for series 10 bearings
  • = 150 for series 2, 3, and 4 bearings
  • = 200 for series 22 bearings
  • = 250 for series 23 bearings
• n — Rotational speed (r/min)
• n_r — Limiting speed for oil lubrication (r/min)
• d_m — Bearing mean diameter = 0.5 × (d + D) (mm)

For cylindrical roller bearings carrying axial loads, the dynamic equivalent load formulas are as follows:

Cylindrical roller bearings are primarily designed to carry radial loads. However, bearings with flanged rings (e.g., NJ, NF, and NUP types) can also accommodate certain axial loads. The axial load capacity is not determined by material fatigue strength but by the load-bearing capacity of the sliding surfaces at the contact area between the rollers and flanges. This depends mainly on the lubrication condition, operating temperature, and heat dissipation capabilities of the bearing.

The allowable axial load can be calculated using the following formula:

Where:

• F_ap — Maximum allowable axial load (N)
• C₀ — Basic static load rating (N)
• F_r — Actual radial load (N)
• n — Operating speed (r/min)
• d — Bearing inner diameter (mm)
• D — Bearing outer diameter (mm)
• K₁ — Coefficient: 0.3 for oil lubrication; 0.5 for grease lubrication
• K₂ — Coefficient: 0.03 for oil lubrication; 0.05 for grease lubrication

To ensure uniform flange loading and sufficient operational precision of the shaft, special attention must be paid to the axial runout of the relevant contact surfaces for cylindrical roller bearings subjected to high axial loads.

Other types of single-row cylindrical roller bearings, such as full-complement self-locking bearings, can also be produced upon customer request.