Constant Section (CS) Bearings
Constant section (CS) bearings maintain the same radial cross section within each series while the bore diameter changes, allowing related bearing sizes to retain a slim and consistent envelope. The product range includes inch and metric configurations, Type A angular-contact, Type C radial-contact and Type X four-point-contact designs, together with open, sealed, chrome-steel, stainless-steel and plated options. TFL supports bearing distributors, importers and multi-line resellers that need Kaydon-style replacement sourcing, mixed-model quotations and cross-reference review. Buyers can send part numbers, drawings or required dimensions, and TFL can coordinate suitable alternatives, custom specifications, OEM or neutral packaging, pre-shipment checks and consolidated delivery.
Consistent Cross-Section Across Sizes
Optimized Space Utilization
Simplified Design and Inventory
Constant Section Bearing Selection and Sourcing Guide
Quick selection: Choose a constant section bearing by cross-section series, bore size and contact type before comparing seals, material, precision, internal fit and lubrication. For replacement inquiries, the complete part number is usually the best starting point. Drawings, dimensions or samples can be added when available to help confirm the closest alternative more quickly.
How to Choose a CS Bearing from the Product List
Start with the required bore, outside diameter and cross-section size. Then determine whether the bearing needs mainly radial support, one-direction axial support, or combined radial, bidirectional axial and moment-load capability. After the basic type is identified, compare operating speed, torque, precision, clearance or preload, sealing, material, lubrication and mounting fits.
Selection Note for Distributors
Do not cross-reference a constant section bearing by bore and outside diameter alone. Bearings with similar boundary dimensions may use Type A, Type C or Type X internal geometry and can differ in preload, clearance, separator, material or precision. For distributor RFQs, include the complete original part number and required quantity whenever possible.
Common Series and Model Range
The current range includes large-bore inch and metric constant-section bearing families with multiple cross-section sizes, materials and contact configurations. Availability varies by series and specification, so the complete designation should be checked before confirming an interchange or quotation.
| Product Group | Representative Series | Available Cross Sections | Typical Options |
|---|---|---|---|
| Open inch series | KAA, KA, KB, KC, KD, KF, KG | 3/16 × 3/16 to 1 × 1 inch | Type A, C or X; open chrome-steel configurations |
| Sealed inch series | JHA, JA, JB, JU, JG | 3/16 × 1/4 to 1 × 1 inch | Type C radial-contact or Type X four-point-contact configurations |
| Stainless-steel series | SAA, SA, SB, SC, SD, SF, SG | 3/16 × 3/16 to 1 × 1 inch | Type A, C or X with corrosion-resistant material options |
| Plated series | NAA, NA, NB, NC, ND, NF, NG | 3/16 × 3/16 to 1 × 1 inch | Chrome-steel bearing configurations with protective surface plating |
| Metric constant-section series | Metric model-number format | 8, 13 and 20 mm cross sections | Type A, C or X in selected sizes |
| Ultra-thin metric series | 2.5 mm series | 2.5 × 2.5 mm cross section | Very low-profile Type A, C or X configurations in selected sizes |
Type A vs. Type C vs. Type X Selection
| Contact Type | Primary Load Requirement | Selection Notes |
|---|---|---|
| Type A: Angular Contact | Radial load plus axial load in one direction | Often used in pairs when bidirectional thrust support, preload or greater system rigidity is required. |
| Type C: Radial Contact | Mainly radial load | Deep raceway geometry can support limited axial load in either direction, but radial loading remains the primary selection basis. |
| Type X: Four-Point Contact | Radial, bidirectional axial and moment loads | Can support multiple load components in one compact bearing position, but combined-load interaction, fit and internal clearance or preload should be checked carefully. |
Open, Sealed and Material Options
Open bearings provide direct lubrication access and are useful when low torque or application-specific lubrication is important. Sealed versions help retain grease and reduce contaminant ingress, but speed, torque and temperature requirements should be checked against the complete specification. Chrome steel is common for general industrial use, while stainless steel or plated configurations can be considered when improved corrosion resistance is required.
How to Read a CS Bearing Number
Take KB020XP0 as an example of a Kaydon-style reference format. K identifies an open AISI 52100 chrome-steel configuration, B identifies the 5/16 × 5/16-inch cross-section series, 020 represents a 2.0-inch nominal bore, X identifies four-point contact, P identifies the separator code, and 0 is the standard precision code in this designation system. Metric references use a different numbering format, so each position and suffix should be checked against the complete specification before interchange.
Key Specifications to Confirm Before Quotation
You do not need to provide every item below before requesting a quotation. The complete bearing number and quantity are often enough for TFL to begin the review. Additional drawings, dimensions or operating requirements help us confirm the specification and replacement options more quickly when the original designation is incomplete or a custom configuration is involved.
| Specification | Why It Matters |
|---|---|
| Complete part number | Identifies material, series, bore size, contact type, separator and precision information. |
| Bore × OD × width | Confirms basic dimensional compatibility and cross-section series. |
| Type A, C or X | Determines the internal contact geometry and supported load directions. |
| Material and surface treatment | Distinguishes chrome steel, stainless steel and plated configurations. |
| Precision and internal fit | Clearance or preload can materially affect torque, rigidity and running accuracy. |
| Open or sealed design | Affects lubrication retention, contamination protection, speed and torque. |
| Lubrication | Special grease, oil or temperature requirements should be identified when applicable. |
| Quantity and annual demand | Helps evaluate MOQ, volume pricing, production planning and suitable sourcing resources. |
| Packaging requirements | Needed for neutral packaging, OEM branding, private label or consolidated distributor orders. |
Kaydon-Style Replacement and Cross-Reference Notes
For a Kaydon-style replacement or alternative, send the complete original bearing number together with the required quantity whenever possible. TFL can compare bore, outside diameter, width, A/C/X contact type, material, separator, precision, internal clearance or preload, seals and lubrication before quoting an alternative. A similar part number or dimensional match alone should not be treated as proof of full interchangeability.
Common Applications
Constant section bearings are commonly found in robotic joints, rotary and indexing tables, inspection equipment, medical systems, optical equipment, semiconductor machinery, radar and antenna mechanisms and other compact positioning assemblies. For distributor replacement inquiries, the original part number, dimensions and internal design are normally more useful for cross-reference work than the equipment application alone.
Representative Models for Distributor RFQs
| Model | Configuration | Dimensions | Quotation Use |
|---|---|---|---|
| KAA10CL0 | Open Type C radial contact | 1 × 1.375 × 0.1875 in | Compact KAA-series reference for radial-contact inquiries. |
| KAA10XL0 | Open Type X four-point contact | 1 × 1.375 × 0.1875 in | Useful reference when the same boundary size requires four-point contact geometry. |
| KB020XP0 | Open Type X four-point contact | 2 × 2.625 × 0.3125 in | Representative KB-series Kaydon-style cross-reference model. |
Mixed-Model and Distributor Sourcing from TFL
TFL supports bearing distributors, importers and multi-line resellers that need constant-section bearings together with other bearing types in the same sourcing project. Send a spreadsheet, BOM or RFQ containing original part numbers, quantities, target specifications, materials, precision or preload requirements and packaging instructions.
TFL can compare suitable factory resources, replacement specifications, MOQ, volume pricing, availability and lead time by line item. We can also coordinate samples or customized specifications and consolidate different bearing models into one shipment. Before shipment, we check the agreed model numbers, quantities, visible condition, packaging and basic quality requirements. OEM, private-label and neutral packaging can be reviewed according to model and order quantity.
Request a Mixed-Model CS Bearing Quote
Send your part-number list and quantities to begin the review. Add drawings, target specifications, annual demand or packaging requirements when available for faster cross-reference checking and consolidated pricing.
Kaydon and Reali-Slim are trademarks of their respective owners. TFL is an independent bearing supplier and is not presented as the original brand owner or an authorized distributor. Brand names and part numbers are used only for product identification and cross-reference. Final interchangeability must be confirmed from dimensions, internal design, fit and operating requirements.
FREQUENTLY ASKED QUESTIONS
