61868MA Thin Section Deep Groove Ball Bearing 340x420x38mm Machined Brass Open Cage

1. Product Overview

61868MA belongs to 618 ultra-thin wall single row deep groove ball bearing series, open type without seal or shield, overall dimension 340mm inner bore × 420mm outer diameter × 38mm width.
Suffix explanation:

• MA: Solid machined brass cage, outer ring guided, high rigidity, high temperature resistance, stable performance under high speed and heavy load, good anti-deformation capacity under vibration.

Ultra-slim cross-section design greatly saves radial installation space, retains standard deep raceway structure, can bear bidirectional radial load and moderate bidirectional axial load simultaneously. All rings and steel balls adopt fully quenched GCr15 bearing steel with super precision ground raceway, low friction, low vibration and stable high-speed rotation performance. Open design allows external centralized lubrication system oil supply, suitable for equipment with independent sealing structure. Widely used for wind power auxiliary equipment, large industrial rotary tables, heavy-duty packaging machinery, large machine tool spindles, metallurgical conveying rollers and large precision transmission equipment requiring large bore and compact radial layout.

2. Technical Specifications

Mounting shoulder dimension drawings, centralized lubrication layout guide and full load performance test reports can be provided on customer demand.

3. Core Advantages

1. Ultra-thin wall slim cross-section structure, small outer-inner diameter difference, greatly reduce equipment radial occupation space, realize lightweight large bore rotary structure design.
2. MA solid machined brass cage, thickened integrated brass structure, strong rigidity, not easy to deform under heavy load and high temperature, stable ball positioning for long-term continuous high-speed operation.
3. Open non-sealed design, smooth oil circulation channel, match external automatic oil supply lubrication system, effectively reduce bearing temperature rise during heavy load long-hour operation.
4. Standard deep groove raceway design, uniformly bear radial load and two-way moderate axial thrust, flexible matching various composite load working conditions.
5. Ultra-precision superfinishing grinding inner and outer ring raceways and steel ball surface, extremely low surface roughness, effectively reduce friction loss and running noise.
6. Fully quenched high hardness GCr15 steel, stable metallographic structure, excellent contact fatigue resistance and wear resistance, extend service life under cyclic heavy load and vibration environment.
7. Standard metric interchangeable overall dimension, fully compatible with global 61868MA thin wall bearings, direct replacement without modifying large equipment housing and shaft structure.
8. Rich customizable options: P0/P6/P5 precision grade, C3/C4 enlarged clearance group, ZZ/2RS sealing upgrade, stainless steel material, OEM outer ring laser marking, neutral export anti-rust carton, high temperature resistant special grease filling.

4. Application Scenarios

61868MA large bore thin wall open deep groove ball bearing with brass cage is compact large-size rotary spare part for 340mm shaft equipment needing space-saving radial layout and external lubrication:

• Wind power generator auxiliary rotary support assemblies
• Large CNC machine tool turntable and spindle supporting bearing positions
• Heavy-duty automatic packaging large rotating roller transmission units
• Metallurgical production line long-distance heavy load conveying roller sets
• Large precision rotary platform, large industrial fan main shaft assemblies

Aftermarket interchangeable 618 ultra-thin wall deep groove ball bearing
Large bore slim high-speed bearing solution for wind power equipment manufacturers, heavy machine tool OEM factories and large metallurgical machinery bulk maintenance procurement.

5. Why Choose GQZ Bearing

• We have 25 years of mature professional manufacturing experience for 618 series ultra-thin wall deep groove ball bearings including 61868MA large size models.
• Our 61868MA bearings adopt unified international standard dimensions, consistent dynamic/static load parameters, MA brass cage processing precision and CN clearance tolerance standards, fully dimensionally interchangeable with global standard brand thin wall bearings.
• Complete OEM & ODM customized service system, supporting multi-precision grades, multiple clearance groups, sealing structure transformation and special temperature-resistant lubricant filling personalized requirements.
• Strict pre-delivery full quality inspection flow: GCr15 raw material composition and hardness test, steel ball automatic sorting screening, long-cycle high-speed heavy load rotation aging test, brass cage flatness and dimensional full inspection.
• Professional thin wall bearing technical team provides one-to-one radial-axial combined load calculation, large shaft-housing fit tolerance guidance and centralized lubrication layout design tips within 24 working hours.
• Large standardized large-size precision bearing production workshop provides competitive factory direct bulk wholesale price, stable long-term mass supply for global wind power, heavy machine tool and metallurgical large machinery spare parts purchasers.
• We specialize in large bore ultra-thin wall deep groove ball bearings with solid brass MA cage, strict raceway super grinding quality control and ISO metric standard dimensions, committed to long-term stable win-win cooperation with large heavy-duty precision transmission equipment suppliers.

6. Quality Control

• Raw material chemical composition, internal crack defect and hardness inspection for GCr15 inner ring, outer ring and steel ball blanks
• Precision turning forming processing, multiple stress relief tempering cycles, ultra-precision superfinishing grinding for thin wall deep groove raceway surfaces
• Steel ball high temperature overall quenching, mirror polishing and high precision automatic sorting production line
• Solid brass blank cutting, precise milling and drilling processing for MA machined cage, cage roundness and gap inspection, pre-filled anti-wear grease treatment process
• Targeted professional performance testing: 61868MA long cycle high-speed temperature rise rotation aging test, composite radial-axial load fatigue wear resistance detection, brass cage high temperature deformation simulation test
• Comprehensive re-inspection of overall dimensional tolerance, raceway surface finish and cage matching precision before anti-rust oil coating and export moisture-proof carton packaging.

Each production batch of 61868MA bearings undergoes large rotary table and wind power equipment simulation cycle rotation test to guarantee stable low-friction high-speed heavy load support performance for 340mm shaft large-size slim transmission systems.

7. Get A Quote Now

If you need 61868MA 340x420x38 ultra-thin wall deep groove ball bearings with solid brass cage for wind power / heavy machine tool manufacturing, large equipment assembly and metallurgical machinery maintenance bulk matching, send your purchase demand directly.
Complete professional one-stop supporting services after sending inquiry:

• Formal official detailed quotation reply within 24 working hours
• One-to-one radial and bidirectional axial combined load calculation, large shaft-housing fit tolerance and external lubrication layout technical support provided by professional bearing engineers
• Customized bearing performance upgrade options including multi-precision grades, enlarged clearance groups and contact sealing structure transformation
• Favorable factory direct bulk wholesale price for large quantity single model orders of 61868MA

Please provide purchase quantity, actual working conditions (continuous high speed / heavy radial load / high temperature environment) to obtain complete official quotation documents.

8. FAQ