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<\/p>\nMany practitioners are often confused by complicated bearing codes and fail to figure out the meaning of each number and letter. For this reason, Wuxi USU Bearing compiles this popular science handbook on bearing designations, systematically elaborating core knowledge including classification of bearing codes, national standards, prefix and suffix codes. It is easy to understand and highly practical. Feel free to collect it for instant reference anytime.<\/p>\n
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The core identification rule of bearing codes lies in the first digit or the combination of the first two digits from the left. Different combinations stand for distinct bearing types, which is the fundamental and most commonly used method for daily bearing selection.<\/p>\n
6<\/strong>: Deep Groove Ball Bearing (Type 0). Widely applied in motors, household appliances, automobile wheel hubs and other scenarios. USU covers all conventional mass-production models.<\/p>\n 4<\/strong>: Double-row Deep Groove Ball Bearing (Type 0). Higher load capacity than standard deep groove ball bearings, suitable for heavy-load equipment.<\/p>\n 1 \/ 2<\/strong>: Self-aligning Ball Bearing (Type 1). Normally marked with four basic digits, capable of automatic self-alignment, ideal for shafts with deflection or installation deviation.<\/p>\n 21\/22\/23\/24<\/strong>: Spherical Roller Bearing (Type 3). Featuring strong load capacity and self-aligning performance, widely used in mines, wind power equipment, vibrating screens and other heavy-duty working conditions.<\/p>\n N<\/strong>: Cylindrical Roller Bearing (Type 2), including short cylindrical roller bearings and partial needle roller bearings, outstanding in radial load bearing capacity.<\/p>\n NU: Inner ring without ribs<\/p>\n NJ: Inner ring with single rib<\/p>\n NF: Outer ring with single rib<\/p>\n N: Outer ring without ribs<\/p>\n NN: Double-row cylindrical roller bearing without outer ring ribs<\/p>\n NNU: Double-row cylindrical roller bearing without inner ring ribs<\/p>\n Roller length is at least 5 times its diameter, main sub-types:<\/p>\n NA: Drawn outer ring needle roller bearing<\/p>\n NK: Stamped outer shell needle roller bearing<\/p>\n K: Needle roller and cage assembly (no inner & outer rings)<\/p>\n 7<\/strong>: Angular Contact Ball Bearing (Type 6). High precision, suitable for high-speed equipment such as machine tool spindles and precision instruments. USU supports customized contact angles.<\/p>\n 3<\/strong>: Metric Tapered Roller Bearing (Type 7). Able to bear combined radial and axial loads, commonly used in automobile wheel hubs and construction machinery.<\/p>\n 51\/52\/53<\/strong>: Thrust Angular Contact Ball Bearing (Type 8), marked with five basic digits, applicable to equipment bearing both radial and axial loads.<\/p>\n 81<\/strong>: Thrust Short Cylindrical Roller Bearing (Type 9). Mainly bearing axial loads, fit for low-speed and heavy-load occasions.<\/p>\n 29<\/strong>: Spherical Thrust Roller Bearing (Type 9). Excellent axial load capacity and self-aligning property, widely used in hydroelectric generators and heavy machinery.<\/p>\n Bearing production, inspection and selection shall comply with national and industrial standards. Below are commonly adopted standards for reference:<\/p>\n GB\/T 305-1998 Rolling bearings \u2014 Snap ring grooves and snap rings on outer rings \u2014 Dimensions and tolerances<\/p>\n GB\/T 308-2002 Rolling bearing steel balls<\/p>\n GB\/T 309-2000 Rolling bearing needles<\/p>\n GB\/T 4661-2002 Rolling bearings \u2014 Cylindrical rollers<\/p>\n GB\/T 4662-2003 Rolling bearings \u2014 Static load rating<\/p>\n GB\/T 6391-2003 Rolling bearings \u2014 Dynamic load rating and rating life<\/p>\n JB\/T 3034-1993 Rolling bearings \u2014 Oil-sealed rust-proof packaging<\/p>\n JB\/T 3573-2004 Rolling bearings \u2014 Measuring method for radial internal clearance<\/p>\n JB\/T 6639-2004 Rolling bearing parts \u2014 Technical specifications for skeleton nitrile rubber seals<\/p>\n JB\/T 6641-2007 Rolling bearings \u2014 Residual magnetism and its evaluation method<\/p>\n JB\/T 6642-2004 Rolling bearing parts \u2014 Measuring and evaluating method for roundness and waviness errors<\/p>\n JB\/T 7048-2002 Rolling bearing parts \u2014 Engineering plastic cages<\/p>\n JB\/T 7050-2005 Rolling bearings \u2014 Cleanliness evaluation method<\/p>\n JB\/T 7051-2006 Rolling bearing parts \u2014 Measurement and evaluation of surface roughness<\/p>\n JB\/T 7361-2007 Rolling bearing parts \u2014 Hardness test method<\/p>\n JB\/T 7752-2005 Technical specifications for sealed deep groove ball bearings<\/p>\n JB\/T 8196-1996 Rolling bearings \u2014 Residual magnetism of rolling elements and evaluation method<\/p>\n JB\/T 8571-1997 Test procedures for dustproof, grease leakage and temperature rise performance of sealed deep groove ball bearings<\/p>\n JB\/T 8921-1999 Inspection rules for rolling bearings and components<\/p>\n JB\/T 10336-2002 Supplementary technical specifications for rolling bearings and components<\/p>\n JB\/T 50013-2000 Test procedures for service life and reliability of rolling bearings<\/p>\n JB\/T 50093-1997 Evaluation method for service life and reliability of rolling bearings<\/p>\n Prefix codes indicate special bearing structures and reflect installation and combination forms. Rules: Code R is placed directly before basic codes; other prefix codes are separated by a dot.<\/p>\n R : Bearings without separable inner or outer ring, e.g. RNU207<\/p>\n WS : Shaft ring of thrust cylindrical roller bearing, e.g. WS.81112<\/p>\n Placed after basic codes, suffix codes specify detailed parameters including internal structure, overall dimensions, sealing type, cage type, tolerance grade, clearance and more. Multiple suffix codes are arranged in fixed order.<\/p>\n Reflect subtle internal structural changes and affect load capacity, contact angle and other core performances.<\/p>\n A\/B\/C\/D\/E: Modified internal structure<\/p>\n Example: 7205C (15\u00b0 contact angle), 7205E (25\u00b0 contact angle), 7205B (40\u00b0 contact angle)<\/p>\n E: Reinforced structure for higher load capacity<\/p>\n VH: Full complement cylindrical roller bearing with roller self-locking<\/p>\n Match diversified installation requirements<\/p>\n DA: Separable double-row angular contact ball bearing with double half inner rings<\/p>\n DZ: Cylindrical outer diameter roller bearing<\/p>\n K: Tapered bore bearing, taper ratio 1:12<\/p>\n K30: Tapered bore bearing, taper ratio 1:30<\/p>\n 2LS: Double-row cylindrical roller bearing with double inner rings and double dust shields<\/p>\n N: Bearing with snap ring groove on outer ring<\/p>\n NR: Bearing with snap ring groove and snap ring on outer ring<\/p>\n N2: Four-point contact ball bearing with two outer ring grooves<\/p>\n S: Bearing with lubrication groove and holes on outer ring<\/p>\n X: Dimensions conforming to international standards<\/p>\n Z series: Special technical requirements<\/p>\n ZZ: Roller bearing with two outer ring guide collars<\/p>\n Adapt to various harsh working environments with dust and moisture<\/p>\n RSR: Single-side rubber seal<\/p>\n 2RSR: Double-side rubber seals<\/p>\n ZR: Single-side dust shield<\/p>\n 2ZR: Double-side dust shields<\/p>\n ZRN: One side dust shield, one side outer ring snap groove<\/p>\n 2ZRN: Double-side dust shields plus outer ring snap groove<\/p>\n Determine bearing operation stability and wear resistance, divided into solid cages and stamped cages<\/p>\n Steel cage: F, FA, FB, FH, FP, FV etc.<\/p>\n Light metal cage: L, LA, LB, LP etc.<\/p>\n Brass cage: M, MA, MB, MP etc.<\/p>\n Phenolic laminated fabric cage: T, TA, TB, TP etc.<\/p>\n Engineering plastic cage: TN, TNH<\/p>\n Glass fiber reinforced polyamide cage: TV, TVH etc.<\/p>\n J: Steel plate stamped cage<\/p>\n JN: Riveted cage for deep groove ball bearings<\/p>\n Numbers added to cage codes represent structural adjustments for transitional use.<\/p>\n V: Full complement rolling element bearing<\/p>\n VT: Full complement bearing with spacer elements<\/p>\n P0: Standard general precision (omitted in marking)<\/p>\n P6 \/ P6X \/ P5 \/ P4 \/ P2: Higher precision grades in sequence<\/p>\n SP: Composite precision for double-row cylindrical roller bearings<\/p>\n UP: Ultra-high precision for double-row cylindrical roller bearings<\/p>\n HG: Special high precision for spindle bearings<\/p>\n Affect bearing flexibility and stability<\/p>\n C1 < C2 < C0(standard, omitted) < C3 < C4 < C5<\/p>\n Combination rule: Tolerance grade + clearance code, e.g. P63 = P6 grade + C3 clearance<\/p>\n Custom clearance: Mark radial clearance after R, axial clearance after A with micron values, e.g. 6210.R10.20<\/p>\n Applied to household appliances and precision equipment<\/p>\n F3: Low-noise large-size bearings<\/p>\n G: Low-noise small-size deep groove ball bearings<\/p>\n S0~S: Different tempering treatments for maximum working temperature from 150\u2103 to 350\u2103<\/p>\n Mark customized manufacturing, inspection and structural specifications<\/p>\n Used for paired installation to guarantee assembly precision<\/p>\n K1~K11: Different paired mounting forms for single\/double-direction axial load, back-to-back \/ face-to-face arrangement<\/p>\n UA: Slight axial clearance after matching<\/p>\n UO: Zero clearance after matching<\/p>\n UL: Light preload after matching<\/p>\n Combined codes of precision grade, cage type and preload for professional machine tool spindles<\/p>\n Mastering bearing code interpretation enables fast and accurate model selection and reduces errors in procurement and maintenance.<\/p>\n Wuxi USU Bearing Co., Ltd. specializes in the production and customization of full-series bearings including deep groove ball bearings, self-aligning ball bearings, cylindrical roller bearings and angular contact ball bearings. All products are manufactured in strict accordance with international standards. We provide professional selection guidance and customized production services based on actual equipment demands and working conditions.<\/p>\n If you have any questions about bearing code interpretation, model selection, bulk procurement or personalized customization, please feel free to contact us. Our professional engineers will provide one-on-one technical support to help you select and apply bearings properly.<\/p>\n Bearing designation is the unique identity mark of bearings, standing for specific structure, performance and applicable scenarios. This handbook covers all core interpretation knowledge with strong practicability for permanent collection.<\/p>\n Adhering to the tenet of Premium Products & Professional Services<\/strong>, Wuxi USU Bearing keeps deep rooting in the bearing industry, supplying cost-effective and highly reliable bearing products for diverse industrial fields to boost efficient industrial operation.<\/p>","protected":false},"excerpt":{"rendered":" Wuxi USU Bearing has been engaged in bearing production and manufacturing for many years, focusing on the R&D and application of various bearings.<\/p>","protected":false},"author":1,"featured_media":409357,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-409267","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news"],"_links":{"self":[{"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/posts\/409267","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/comments?post=409267"}],"version-history":[{"count":6,"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/posts\/409267\/revisions"}],"predecessor-version":[{"id":409365,"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/posts\/409267\/revisions\/409365"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/media\/409357"}],"wp:attachment":[{"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/media?parent=409267"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/categories?post=409267"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.usubearings.com\/russian\/wp-json\/wp\/v2\/tags?post=409267"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}Sub-codes of Cylindrical Roller Bearings<\/b><\/strong><\/h3>\n
Needle Roller Bearings (Type 4)<\/b><\/strong><\/h3>\n
II. National Standards for Bearings (Must-read for Selection & Procurement)<\/b><\/strong><\/h2>\n
III. Bearing Prefix Codes (Supplementary Structural Description)<\/b><\/strong><\/h2>\n
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IV. Bearing Suffix Codes (Core Detailed Interpretation)<\/b><\/strong><\/h2>\n
1. Internal Structure Suffix Codes<\/b><\/strong><\/h3>\n
2. Overall Dimension & External Structure Codes<\/b><\/strong><\/h3>\n
3. Sealing & Dustproof Codes<\/b><\/strong><\/h3>\n
4. Cage & Cage Material Codes<\/b><\/strong><\/h3>\n
Solid Cage<\/b><\/strong><\/h4>\n
Stamped Cage<\/b><\/strong><\/h4>\n
5. Modified Cage Structure<\/b><\/strong><\/h3>\n
6. Cageless Bearings<\/b><\/strong><\/h3>\n
7. Tolerance Grade Codes (Dimensional & Rotational Precision)<\/b><\/strong><\/h3>\n
8. Internal Clearance Codes<\/b><\/strong><\/h3>\n
9. Low Noise Bearings<\/b><\/strong><\/h3>\n
10. Heat Treatment Codes (High-temperature Resistance)<\/b><\/strong><\/h3>\n
11. Special Technical Requirements<\/b><\/strong><\/h3>\n
12. Matched Bearings & Machine Tool Spindle Bearings<\/b><\/strong><\/h3>\n
13. Universal Matched Bearings<\/b><\/strong><\/h3>\n
14. High-precision Spindle Bearing Exclusive Codes<\/b><\/strong><\/h3>\n
V. Bearing Selection Guidance from Wuxi USU<\/b><\/strong><\/h2>\n
Final Note<\/b><\/strong><\/h2>\n