Product Overview

The NMT 7014 CDGA/HCP4A is an open, universally matchable single-row super-precision hybrid ceramic angular contact ball bearing. With a 70 mm bore, 110 mm outer diameter, and 20 mm width, this bearing features a 15° contact angle (CD type) and D-type high-capacity design, combined with silicon nitride (Si₃N₄) hybrid ceramic rolling elements (HC)  and a phenolic resin cage, factory-preset with Class A measured load preload (GA) . It integrates ultra-precision rotational accuracy, high load capacity, excellent high-speed performance, and universal matchable flexibility into a single package, accommodating radial and unidirectional axial loads simultaneously.

 

The bearing offers a basic dynamic load rating of 52 kN (11,690 lbf) and a static load rating of 45.5 kN (10,229 lbf) . Manufactured to the P4A super-precision tolerance class with a 15° contact angle and hybrid ceramic technology, the bearing achieves a limiting speed of 14,000 r/min under grease lubrication and 22,000 r/min under oil lubrication. The bearing weighs only 0.49 kg with an operating temperature range of -30°C to 110°C.

 

Model Code Decoding – Understanding NMT 7014 CDGA/HCP4A

Code Meaning

7014 Basic series designation, 70 mm bore, 110 mm OD

CD 15° contact angle design – offers higher limiting speed and lower heat generation than 25° designs

D D-type high-capacity design – optimized internal geometry for higher load capacity

G Single bearing (not a pre-assembled set)

A Class A measured load preload – ideal for high-speed precision applications

HC Hybrid ceramic – rolling elements made of bearing-grade silicon nitride (Si₃N₄) 

P4A Super-precision tolerance class – dimensional accuracy to ISO P4 class

Core Value: GA universal matchability (SU) means every NMT 7014 CDGA/HCP4A bearing's end-face height difference and parallelism are tightly controlled, allowing any two bearings of the same model to be directly paired without selective shimming or additional grinding, providing effective load sharing within a predetermined preload range. The CD-type 15° contact angle generates less frictional heat at equivalent speeds, offering higher limiting speed potential than 25° designs. The D-type high-capacity design, with optimized rolling element parameters – ball diameter 12.7 mm, 19 ceramic balls per bearing – achieves outstanding load capacity. HC hybrid ceramic technology drastically reduces centrifugal forces and frictional heat at high speeds. P4A super-precision ensures bore and OD tolerances are controlled within -0.004 mm to 0 – these five elements work together to make this bearing a high-performance yet flexible flagship general-purpose precision bearing.

 

Core Performance Advantages

1. 15° Contact Angle (CD Type) + D-Type High-Capacity Design – Ultra-High Speed and High Load Combined

The 15° small contact angle generates less frictional heat at equivalent speeds, offering higher limiting speed potential than 25° designs, with a limiting speed of 22,000 r/min under oil-air lubrication. The D-type high-capacity design, with optimized rolling element parameters – ball diameter 12.7 mm, 19 ceramic balls per bearing – achieves an outstanding 52 kN (11,690 lbf) dynamic and 45.5 kN (10,229 lbf) static load rating. This bearing is specifically designed for heavy loads at relatively high speeds.

 

2. Hybrid Ceramic Technology – A Leap in High-Speed Performance

Silicon nitride (Si₃N₄) ceramic balls have only 60% the density of bearing steel, drastically reducing centrifugal forces and frictional heat at high speeds. Ceramic materials also offer lower thermal expansion coefficients and higher elastic modulus, effectively suppressing geometric deformation at high speeds while improving seizure resistance and lubrication-starvation tolerance, significantly extending bearing service life.

 

3. Universal Matchable (GA) – One Inventory, Infinite Arrangements

GA universal matchability delivers outstanding value:

 

Simplified inventory: Stock a single model to cover DB (<>), DF (><), and DT (>>) pairing needs

 

On-site flexibility: Change arrangements during commissioning based on actual load directions

 

Easy maintenance: Replace individual bearings without replacing entire matched sets

 

No shims required: Install directly to achieve design preload, providing effective load sharing within a predetermined preload range

 

4. Class A Measured Load Preload – Ideal for High-Speed Precision Applications

Class A measured load preload provides precise internal contact stiffness for high-speed spindles – eliminating internal clearance, reducing vibration and noise at high speeds, while avoiding excessive temperature rise from over-preloading. This ensures stable temperature performance even at the 22,000 r/min oil-air lubrication limiting speed.

 

5. P4A Super-Precision Grade – Micron-Level Accuracy

The P4A tolerance class (dimensional accuracy to ISO P4 class) guarantees minimal radial runout and axial play. Bore and outside diameter tolerances are -0.004 mm to 0, meeting stringent surface quality and dimensional consistency requirements. Operating temperature range is -30°C to 110°C.

 

6. Lightweight Phenolic Resin Cage

The lightweight high-strength phenolic resin cage provides excellent guidance accuracy and low friction at high speeds, contributing to reduced centrifugal forces, friction, and heat generation – a key factor in achieving the 22,000 r/min oil-air lubrication limiting speed.

 

7. Steel Rings + Ceramic Balls – High Rigidity, High Speed, Cost-Effectiveness

Premium chrome steel rings combined with silicon nitride ceramic balls deliver the high rigidity and impact resistance of all-steel bearings along with the high-speed low-heat characteristics of hybrid ceramic technology. This combination offers significant cost advantages over full ceramic bearings while maintaining superior performance.

 

8. Open Design – Flexible Lubrication Options

This bearing features an open design with no seals, allowing flexible selection of lubrication methods based on application – grease lubrication for general applications (14,000 r/min), oil-air lubrication for high-speed precision machining (22,000 r/min).

 

9. Clear Performance Specifications

 

Parameter Value

Bore d 70 mm

Outer Diameter D 110 mm

Width B 20 mm

Contact Angle 15°

Dynamic Load Rating C 52 kN (11,690 lbf)

Static Load Rating C₀ 45.5 kN (10,229 lbf)

Ball Diameter Dw 12.7 mm

Ceramic Balls per Bearing 19

Speed (Grease) 14,000 r/min

Speed (Oil-Air) 22,000 r/min

Ball Material Silicon Nitride (Si₃N₄)

Ring Material Chrome Steel

Cage Material Phenolic Resin

Seal Type Open (Unsealed)

Tolerance Class P4A

Preload Class A (Measured Load)

Arrangement Universal Matchable (SU)

Weight 0.49 kg

Temperature Range -30°C to 110°C

Typical Applications

The NMT 7014 CDGA/HCP4A, with its hybrid ceramic high-speed performance, D-type high-capacity design, and universal matchable flexibility, covers an exceptionally wide range of high-end applications:

 

High-Speed Machine Tool Spindles – CNC machine tools, precision grinders, milling center spindles

 

High-Speed Electric Spindles – high-speed rotary units

 

Machining Center Spindles – vertical/horizontal spindle systems

 

Precision Rotary Tables – high-accuracy rotary positioning

 

Aerospace Components – gyroscopes, actuators, jet engine parts

 

Medical Equipment – high-speed dental drills and medical imaging devices

 

Semiconductor Manufacturing Equipment – precision wafer processing spindles

 

Industrial Robots – high-precision transmission mechanisms and rotary axes

 

Important Installation Notes

✅ This bearing is universally matchable (GA) – any two bearings of the same model can be directly paired. Configurable as back-to-back (<>), face-to-face (><), or tandem (>>) arrangements.

 

✅ This bearing is open design – select appropriate lubrication method based on application. To achieve the 22,000 r/min oil-air lubrication limiting speed, oil-air or oil-mist lubrication is recommended; grease lubrication limits speed to 14,000 r/min.

 

✅ For paired installations, using bearings from the same production batch is recommended for optimal consistency.

 

⚠️ This bearing comes with factory-preset Class A measured load preload. No additional preload adjustment is required during installation. However, ensure shaft and housing fits comply with P4A grade requirements (bore/OD tolerance -0.004 mm to 0).

 

⚠️ Ensure the contact angle direction matches the intended load direction – incorrect orientation will eliminate load capacity.

 

⚠️ A single-row angular contact ball bearing can accommodate axial load in one direction only. Paired installations (DB/DF/DT) are required for bidirectional axial load capacity.

 

⚠️ Hybrid ceramic bearings are more sensitive to installation shock. Heat mounting or hydraulic installation methods are recommended – avoid impact on raceways or rolling elements.

 

NMT Quality Commitment

Japan NMT (Enmutī) applies strict Japanese quality standards to every 7014 CDGA/HCP4A bearing – from ring material (high-purity chrome steel), ceramic balls (HIP silicon nitride), to superfinishing processes. End-face height difference, parallelism, and contact angle deviation of each bearing are tightly controlled to ensure universal matchability consistency across any two bearings of the same model. The combination of 15° contact angle (CD type), D-type high-capacity design, hybrid ceramic technology (HC), P4A precision, Class A measured load preload, and universal matchable flexibility makes this bearing the flagship general-purpose precision bearing in the NMT 7014 series – offering the perfect balance of high performance, high load capacity, and flexible arrangement.

 

Choose NMT 7014 CDGA/HCP4A for:

 

✅ 15° contact angle + D-type high capacity – 52 kN (11,690 lbf) high load capacity

 

✅ Hybrid ceramic technology – 22,000 r/min oil-air lubrication limiting speed

 

✅ Universal matchable – one inventory, infinite arrangements

 

✅ Class A measured load preload – ideal for high-speed precision applications

 

✅ P4A super-precision running accuracy – bore/OD tolerance -0.004 mm to 0

 

✅ Lightweight phenolic resin cage – low friction, low noise, high speed

 

✅ Steel rings + ceramic balls – high rigidity, high speed, cost-effectiveness

 

✅ Open design – flexible lubrication options