NKIA5904- XL / NKIA5904 Angular Contact Ball Bearing / X - life Needle Roller 20*37*23mm

1.Product Overview

NKIA5904 and NKIA5904-XL are metric integrated combined needle roller + single-direction angular contact ball composite bearings, unified overall dimension inner bore d=20mm, outer diameter D=37mm, total width B=23mm, inner ring raceway diameter F=25mm, minimum chamfer r=0.3mm. NKIA series integrates two rolling structures into one unit: dense needle rollers undertake heavy radial load, angular contact steel balls bear unidirectional axial thrust load, realize radial + single axial positioning in limited thin cross-section space, separable inner ring design for easy installation and disassemblySKF 集....

• NKIA5904: Standard basic composite bearing, stable standard load performance, cost-effective for conventional medium-speed light-impact equipment;
• NKIA5904-XL: XL X-life upgraded optimized version, improved raceway grinding precision, uniform rolling element grading, enhanced fatigue resistance and extended service life, suitable for continuous long-cycle high-speed operation working conditions.

All rings, needle rollers and steel balls adopt GCr15 bearing steel overall quenching; stamped steel cages separate rolling elements evenly to avoid collision abrasion. Open both ends design supports oil bath lubrication with excellent heat dissipation, only bear radial load plus one-way axial load, widely used for miniature gearboxes, automation rotary tables, textile winding shafts, packaging machinery cam assemblies and compact transmission equipment with strict radial space restrictions.

2.Technical Specifications

Unified Base Standard Parameters

Inner bore d: 20 mm
Outer diameter D: 37 mm
Overall width B: 23 mm
Inner ring raceway diameter F: 25 mm
Minimum chamfer r: 0.3 mm
Structure: Combined needle roller + single-direction angular contact ball bearing, separable inner ring, stamped steel cage
Rolling element & ring material: GCr15 high-carbon chrome bearing steel
Standard radial clearance: CN normal clearance, C3 enlarged clearance customizable
Reference speed: 14000 r/min
Limiting oil lubrication speed: 17200 r/min
Operating temperature range: -20℃ ~ 110℃
Net weight: 0.105 kg

NKIA5904

Basic dynamic radial load Cr: 21600 N
Basic static radial load C0r: 28000 N
Basic dynamic axial load Ca: 3790 N
Basic static axial load C0a: 4210 N
Fatigue limit load Pu radial: 3350 N
Service life rating: Standard industrial design life

NKIA5904-XL

Basic dynamic radial load Cr: 23700 N
Basic static radial load C0r: 25500 N
Basic dynamic axial load Ca: 4900 N
Basic static axial load C0a: 7400 N
Fatigue limit load Pu radial: 4700 N
Service life rating: XL upgraded long-life anti-fatigue optimized version
Complete dimension drawings, load curve and high-speed durability test data of two models are available upon customer request.

3.Key Advantages

1. All-in-one composite integrated structure, realize radial heavy load + single axial positioning bearing function in ultra-thin radial cross-section, save housing design space and reduce total bearing set quantity
2. Two performance grades (standard NKIA5904 / XL upgraded NKIA5904-XL) match different working conditions: general intermittent operation and continuous long-cycle high-speed heavy load operation
3. Separable inner ring structure, convenient press-fit assembly and disassembly on shaft, no interference disassembly damage to shaft or bearing raceway
4. Double rolling element layout: needle rollers provide large contact radial bearing capacity, angular contact balls reliably resist one-way axial thrust to limit shaft single-side axial displacement
5. Open through structure fully immersed in lubricating oil for sufficient cooling, stable high-speed rotation without high-temperature ablation failure under long continuous operation
6. Customizable options: single/double Z metal dust shields, RS rubber contact seals, C3 clearance upgrade, P5 high precision, OEM laser marking, high-temperature special grease filling

Effectively simplify compact transmission positioning structure and reduce equipment axial displacement vibration failure rate

4.Applications

This NKIA5904 / NKIA5904-XL dual-spec combined needle angular contact bearing set is widely matched for light & medium compact industrial automation equipment:

• Miniature reduction gearboxes, small transmission box input/output shaft radial-axial positioning assemblies
• Automation rotary indexing tables, miniature cam rotary positioning mechanism supporting bearings
• Textile yarn winding machinery, small loom tension roller one-way thrust support units
• Food packaging equipment, light printing machinery high-speed compact transmission shafts
• Micro hydraulic auxiliary shafts, medical small equipment lightweight rotary positioning components
• Aftermarket replacement spare parts for 20mm bore single-direction radial-axial composite needle bearing equipment

Ideal dual-performance compact locating bearing solution for narrow radial space industrial rotary machinery

5.Why Choose GQZ Bearing

• 25 years of professional NKIA series combined needle angular contact composite bearing manufacturing experience
• Two models fully dimensionally interchangeable with international standard NKIA5904 series bearings, consistent installation size and assembly tolerance
• Complete OEM & ODM customized service supporting ZZ metal shields, RS rubber sealing, enlarged C3 clearance and high precision upgrade
• Full-process strict inspection: raw material hardness test, raceway ultra-precision grinding detection, rolling element sorting uniformity and high-speed reciprocating fatigue cycle testing before delivery
• Professional composite bearing engineering team provides housing & shaft matching tolerance installation guidance within 24 hours
• Stable mass production assembly lines with preferential bulk wholesale price for long-term automation and textile machinery manufacturers

We focus on compact space-saving design, stable radial-axial combined load performance and long-term win-win cooperation with global industrial equipment buyers

6.Quality Control

• Raw material chemical composition and surface hardness inspection of GCr15 chrome bearing steel
• Precision turning, quenching tempering and raceway mirror superfinishing processing for inner & outer rings
• Constant temperature stress relief heat treatment to stabilize ring anti-deformation performance under combined radial-axial alternating load
• Targeted differentiated performance testing: NKIA5904 standard cycle durability test, NKIA5904-XL X-life long-term fatigue resistance accelerated aging test
• Needle roller & steel ball sorting, stamped steel cage assembly and full dimensional & appearance re-inspection for each model before anti-rust oil packaging and shipment

Every batch of NKIA5904 series bearings passes full sampling high-speed reciprocating radial-axial combined load cycle test to guarantee stable long-term positioning operation inside compact transmission equipment

7.Get a Quote Now

If you need cost-effective standard NKIA5904 and long-life upgraded NKIA5904-XL combined needle angular contact composite bearings for miniature gearbox and automation rotary positioning equipment, send your inquiry to us directly.
You will receive full professional supporting services after submitting inquiry:

• Fast official factory quotation reply within 24 hours
• One-on-one housing bore & shaft matching tolerance parameter installation guidance by professional composite bearing engineers
• Customized bearing solution suggestions including ZZ double metal shield and RS sealed variants and C3 enlarged clearance options
• Competitive direct factory bulk wholesale price for mixed two-model combined bulk orders

Send your required purchase quantity of each model and equipment operating speed & load environment to obtain detailed formal quotation

8.FAQ

1. Q1: What is the difference between NKIA5904 and NKIA5904-XL?
   A1: Outer installation dimensions are completely identical; NKIA5904 is standard basic version for intermittent medium-speed equipment; NKIA5904-XL is X-life upgraded long-life optimized model with higher fatigue limit load, suitable for 24h continuous high-speed heavy-duty operation.
2. Q2: What load types can NKIA composite bearings bear?
   A2: It can bear heavy radial load simultaneously with unidirectional axial thrust load, cannot bear bidirectional axial load; choose NKIB series if bidirectional axial positioning is required.
3. Q3: What is the advantage of separable inner ring design?
   A3: The inner ring can be installed separately on the shaft first, then the outer ring with needle and ball assemblies is pressed into the housing, greatly reducing assembly difficulty and avoiding bearing scratch during installation.