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Cylindrical Roller Bearings from China Suppliers - High-Quality Factory Products for Optimal Performance

Cylindrical roller bearings are essential components in various industrial applications, categorized into three primary types: single-row, double-row, and four-row cylindrical roller bearings. As a leading supplier in China, our factory specializes in manufacturing high-quality cylindrical roller bearings that meet international standards. Whether you need single-row for basic applications or double-row and four-row configurations for more complex machinery setups, our products are designed to provide superior performance and durability. Explore our range of cylindrical roller bearings and experience the reliability that comes from working with trusted China suppliers

    Single-Row Cylindrical Roller Bearings

    NU-type N-type NJ-type NF-type NUP-type
    NU-type bearings have flanges on both sides of the outer ring and no flanges on the inner ring.
    N-type bearings have flanges on both sides of the inner ring and no flanges on the outer ring.
    These designs allow limited bidirectional axial displacement of the shaft relative to the housing, accommodating length changes caused by thermal expansion. Thus, they are suitable as non-locating bearings.
    NJ-type cylindrical roller bearings have flanges on both sides of the outer ring and one flange on the inner ring.
    NF-type cylindrical roller bearings have flanges on both sides of the inner ring and one flange on the outer ring.

    These provide unidirectional axial positioning of the shaft.

    NUP-type cylindrical roller bearings have flanges on both sides of the outer ring, one flange on the inner ring, and a loose flange on the other side. This enables bidirectional axial positioning of the shaft.

    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

    NN-type NNU-type W33 suffix

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

    NN-type bearings have flanges on the inner ring and no flanges on the outer ring.
    NNU-type bearings have flanges on the outer ring and no flanges on the inner ring.
    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.

    Dimensions

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


    Permitted Tilt Angle

    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:

    Narrow-type bearings (10, 2, 3, and 4 series): 3.5 arcminutes
    Wide-type bearings (22 and 23 series): 1.5 arcminutes
    Larger tilt angles may be permissible depending on the load magnitude and required service life. Double-row cylindrical roller bearings do not permit any tilt angle.

    Tolerances

    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.


    Radial Internal Clearance

    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.


    Cages

    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.

    Bearings with glass fiber-reinforced nylon 66 cages (suffix code TN) are suitable for operating temperatures up to +120°C.
    For applications requiring continuous operation under high temperatures or harsh conditions, solid brass cages (suffix code M) are available.
    Bearings with standard designs using glass fiber-reinforced nylon 66 or brass cages can also be supplied with stamped steel cages upon customer request.

    Minimum Load

    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:

    F_r = K_r × (6 + 4 × n/n_r) × (d_m / 100)²
    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)


    Dynamic and Static Equivalent Loads

    Dynamic equivalent load P = F_r (kN) for cylindrical roller bearings carrying axial loads:

    Dimension series 2 and 3:
    · P = F_r + 0.3F_a    when 0 ≤ F_a/F_r ≤ 0.12
    · P = 0.94F_r + 0.8F_a    when 0.12 < F_a/F_r ≤ 0.3
    Dimension series 22 and 23:
    · P = F_r + 0.2F_a    when 0 ≤ F_a/F_r ≤ 0.18
    · P = 0.94F_r + 0.53F_a    when 0.18 < F_a/F_r ≤ 0.3
    Static equivalent load P_0 = F_r (kN)

    Axial Load Capacity

    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:

    F_ap = K1 × C0 × (1 - F_r / (0.8 × C0)) × (d × D / 1000) × (1000 / n)^0.5 × K2
    Where:

    · F_ap: Maximum allowable axial load (N)

    · C_0: 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)

    · K_1: Coefficient (0.3 for oil lubrication; 0.5 for grease lubrication)

    · K_2: Coefficient (0.03 for oil lubrication; 0.05 for grease lubrication)

    The above formula applies under normal operating conditions and is valid for constant axial loads. For temporarily applied axial loads, multiply the result by 2; for impact loads, multiply by 3.
    The constant axial load F_a acting on the bearing must not exceed 1.2D² (where D is the outer diameter in mm).
    Occasional impact loads must not exceed 3D².

    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.

    Frequently Asked Questions

    QWhat is the difference between NU-type and NJ-type cylindrical roller bearings?
    NU-type bearings have flanges on both sides of the outer ring only, allowing bidirectional axial displacement — making them suitable as non-locating bearings. NJ-type bearings add one flange on the inner ring, enabling unidirectional axial positioning of the shaft.
    QCan cylindrical roller bearings carry axial loads?
    Standard cylindrical roller bearings are designed primarily for radial loads. However, flanged types such as NJ, NF, and NUP can accommodate certain axial loads. The axial load capacity depends on lubrication conditions, operating temperature, and heat dissipation rather than material fatigue strength.
    QWhat tolerance grades are available for cylindrical roller bearings?
    Single-row cylindrical roller bearings are produced up to P5 grade. For machine tool spindle applications, bearings with tapered bores are available in P5 and higher grades, as well as special tolerance classes SP and UP for demanding precision requirements.
    QWhat cage materials are used in cylindrical roller bearings, and how do I choose?
    The most common cage material is glass fiber-reinforced nylon 66 (suffix TN), suitable for temperatures up to +120°C. For high-temperature or harsh operating environments, solid brass cages (suffix M) are recommended. Stamped steel cages are also available on request for standard bearing designs.
    QWhat radial internal clearance options are available?
    Single-row bearings are supplied with basic group clearance as standard, with C3 and C4 options available for certain sizes. Double-row bearings come with C1 clearance as standard; cylindrical bore versions can be supplied with C2 or C3, while tapered bore versions are available with C2 clearance.
    QWhat is the permitted tilt angle for cylindrical roller bearings?
    Narrow-type single-row bearings (series 10, 2, 3, and 4) permit up to 3.5 arcminutes of tilt. Wide-type bearings (series 22 and 23) allow up to 1.5 arcminutes. Double-row cylindrical roller bearings do not permit any tilt angle. Larger angles may be acceptable depending on load and service life requirements.