4T-30311D 55x120x31.5mm Steep Contact Angle Single Row Tapered Roller Bearing

1. Product Overview

4T-30311D is metric single row separable tapered roller bearing, D suffix represents 24°-32° steep large contact angle, complete matched cone and cup set with overall dimension 55×120×31.5mm. Large conical contact angle greatly upgrades unidirectional axial thrust bearing capacity while maintaining strong heavy radial load performance, perfectly fit equipment enduring huge axial impact during operation. Separable inner cone and outer cup structure simplifies mounting, disassembly and field maintenance; open structure supports regular supplementary lubrication to eliminate internal metal wear debris and extend service life. Widely applied to heavy truck drive axles, semi-trailer wheel hubs, construction machinery reducers, loader walking hubs, large tractor differential transmission and mining heavy conveyor rotating parts.

2. Technical Specifications

Model: 4T-30311D
d:55mm, D:120mm, Total assembly width T:31.5mm, Inner ring width B:29mm
Min fillet rs:2.5mm
Dynamic load Cr:132kN, Static load C0r:154kN
Grease limiting speed:2900r/min
Net weight:1.6kg
Structure: Single row tapered roller, D steep large contact angle, separable cone & cup open type
Cage: High-strength stamped steel cage
Material: Vacuum smelting GCr15 bearing steel, hardness HRC60-65
Clearance: Standard CN, C3 loose clearance customizable
Precision: P0 standard, P6 optional
Operating temperature: -40℃ ~ 120℃
Dimension drawings and heavy combined load durability test reports available on request.

3. Core Advantages

• Factory pre-matched complete 4T-30311D cone & cup assembly, D steep angle design delivers superior axial thrust resistance
• Tapered roller structure bears heavy radial + unidirectional axial combined load, stable under frequent road shock and vibration
• Separable inner cone and outer cup design, convenient independent installation and on-site machinery maintenance replacement
• Optimized logarithmic roller profile reduces edge stress and heat generation under long-term continuous heavy load operation
• Open end design allows easy on-site re-lubrication to flush internal metal debris and prolong bearing service cycle
• Standard metric interchangeable dimension, cross compatible with mainstream commercial vehicle and engineering machinery spare parts
• Custom C3 loose clearance, high-temperature anti-pressure chassis grease and outer ring laser marking services available

4. Application Scenarios

• Commercial vehicle transport: Heavy truck front/rear drive axles, semi-trailer wheel hubs, large bus transmission assemblies
• Construction machinery: Excavator auxiliary reducers, loader walking wheel hubs, road roller spindle supports
• Large agricultural equipment: Heavy tractor differential shafts, big harrow main transmission components
• Mining & conveying: Mine heavy belt conveyor roller shafts, stone crusher low-speed heavy load positions

Fit OEM assembly and aftermarket replacement of heavy thrust load vehicle and engineering transmission equipment.

5. Why Choose GQZ Bearing

25 years professional production of 4T series D steep contact angle tapered roller bearings. High-purity vacuum smelting GCr15 steel with full quenching and tempering heat treatment, excellent anti-fatigue performance under long-term alternating heavy axial thrust loads. Full OEM & ODM customization support for clearance grade, special heavy-load anti-wear lubricant and surface marking. Strict full-process inspection flow: raw material hardness test, ultra-precision tapered raceway superfinishing, roller sorting and combined radial-axial heavy load alternating impact aging test. 24-hour professional technical support for axle shaft tolerance matching and periodic relubrication maintenance plans. Factory direct bulk price, sufficient heavy-duty tapered roller bearing spot stock for global truck parts dealers and engineering machinery manufacturers.

6. Quality Control

1. Raw material chemical composition and hardness inspection
2. Integral quenching and stress relief tempering to eliminate internal residual stress
3. CNC ultra-precision inner cone and outer cup tapered raceway mirror grinding
4. High-precision tapered roller screening and stamped steel cage stamping forming
5. Dust-free assembly with heavy-duty anti-wear mechanical grease pre-filling
6. Continuous rotation aging and heavy combined radial-axial load durability cycle testing
7. Full dimension inspection, anti-rust oil coating, neutral moisture-proof export carton packaging

Each batch completes temperature rise and vibration test to guarantee stable long-time heavy thrust load operation for truck axles and construction equipment.

7. Get A Quote

Send inquiries for 4T-30311D steep contact angle tapered roller bearings used on heavy truck drive axles, construction machinery reducers and mining heavy conveyors.
Services after inquiry:

1. Standard formal quotation document delivered within 24 working hours
2. Technical guidance for axle shaft fit tolerance and lubrication cycle arrangement
3. Upgrade options: P6 high precision grade, C3 loose clearance, high-temperature anti-oxidation synthetic grease
4. Competitive factory bulk unit price for large quantity orders

Please state order quantity, working combined load, rotating speed and working environment for complete quotation documents.

8. FAQ