Product Overview

The NMT 7012 ACE/P4ADGA is a pre-assembled duplex universally matchable super-precision angular contact ball bearing set, comprising 2 rows of bearings precision-paired in a universal matchable (SU) configuration. With a total width of 36 mm (18 mm per row × 2), a 60 mm bore, and a 95 mm outer diameter, this set features a 25° contact angle (ACE type) and high-speed E-type design, combined with all-steel rolling elements and a phenolic resin cage, factory-preset with Class A extra light preload (GA) . It integrates ultra-high-speed performance, high load capacity, and flexible arrangement capability into a single package, accommodating radial and unidirectional axial loads simultaneously.

 

The bearing set offers a radial dynamic load rating of 5,850 lbf (26.0 kN) and a radial static load rating of 5,512 lbf (24.5 kN) . The DGA universal matchable suffix indicates that this set features universal matchable (SU) capability – any two sets of the same model can be directly paired without selective shimming or additional grinding. Users can freely configure them in back-to-back (<>), face-to-face (><), or tandem (>>) arrangements. Manufactured to the P4A super-precision tolerance class with Class A extra light preload, the set achieves a limiting speed of 33,000 r/min. The operating temperature range is -30°C to 110°C.

 

Model Code Decoding – Understanding NMT 7012 ACE/P4ADGA

Code Meaning

7012 Basic series designation, 60 mm bore, 95 mm OD

ACE 25° contact angle + High-speed E-type design – 25° contact angle provides superior axial and radial load capacity; E-type offers higher speed capability and can accommodate heavier loads than equivalent B-type designs

P4A Super-precision tolerance class – dimensional accuracy in accordance with ISO Tolerance Class 4, running accuracy better than ISO Tolerance Class 4

DGA Duplex General Arrangement – 2-bearing matched set with universal matchable (SU) capability, factory-preset Class A extra light preload

Core Value: DGA universal matchability means every NMT 7012 ACE/P4ADGA bearing's end-face height difference and parallelism are tightly controlled, allowing any two bearings of the same model to be directly paired without selection or re-grinding. The E-type high-speed design offers higher speed capability and can accommodate heavier loads than equivalent B-type designs. P4A super-precision ensures bore and OD tolerances are controlled within -0.004mm to 0 – these three elements work together to make this bearing set a high-performance yet flexible flagship general-purpose precision bearing solution.

 

Core Performance Advantages

1. High-Speed E-Type Design – Ultra-High Speed and Heavy Load Combined

The E-type high-speed design optimizes internal geometry and rolling element parameters, significantly reducing sliding friction and churning losses at high speeds. Compared to equivalent B-type high-speed bearings, the E-type design offers higher speed capability and can accommodate heavier loads. Combined with a phenolic resin cage, the set achieves a limiting speed of 33,000 r/min.

 

2. 25° Contact Angle – Superior Combined Load Capacity

The 25° contact angle delivers superior axial rigidity while maintaining ample radial capacity, ensuring stability under various load conditions. With optimized rolling element parameters (ball diameter 7.938 mm, 25 balls per bearing), it achieves an outstanding 5,850 lbf (26.0 kN) dynamic and 5,512 lbf (24.5 kN) static load rating within a compact 36 mm total width. The set weighs only 0.84 kg.

 

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

DGA 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

 

4. Class A Extra Light Preload – Ideal for High-Speed Precision Applications

Class A extra light preload provides "just-right" 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 33,000 r/min limiting speeds.

 

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

The P4A tolerance class (dimensional accuracy in accordance with ISO Tolerance Class 4, running accuracy better than ISO Tolerance Class 4) guarantees minimal radial runout and axial play. Bore and outside diameter tolerances are -0.004mm 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 33,000 r/min limiting speed.

 

7. All-Steel Construction – High Rigidity, Impact Resistance, Cost-Effectiveness

Premium chrome steel rings and balls offer higher fracture toughness and impact resistance than hybrid ceramic versions – more reliable under interrupted cutting and accidental overload conditions. All-steel bearings also offer significant cost advantages for high-volume industrial applications.

 

8. Clear Performance Specifications

 

Parameter Value

Bore d 60 mm

Outer Diameter D 95 mm

Total Width B 36 mm (2×18 mm)

Contact Angle 25°

Dynamic Radial Load 5,850 lbf (26.0 kN)

Static Radial Load 5,512 lbf (24.5 kN)

Ball Diameter Dw 7.938 mm

Balls per Bearing 25

Limiting Speed 33,000 r/min

Ball Material Chrome Steel

Ring Material Chrome Steel

Cage Material Phenolic

Seal Type Open

Tolerance Class P4A

Preload Class A (Extra Light)

Arrangement Universal Matchable (SU)

Bearings in Set 2

Weight 0.84 kg

Temperature Range -30°C to 110°C

Typical Applications

The NMT 7012 ACE/P4ADGA, with its E-type high-speed design, P4A super-precision grade, 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 – PCB drilling, 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

 

High-Frequency Motors – high-speed, high-precision motor applications

 

Important Installation Notes

✅ This bearing set is universally matchable (DGA) – any two sets of the same model can be directly paired.

 

✅ This set is open design – select appropriate lubrication method based on application. To achieve the 33,000 r/min limiting speed, oil-air or oil-mist lubrication is recommended.

 

✅ This set comes pre-lubricated from the factory – ready to install out of the box.

 

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

 

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

 

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

 

NMT Quality Commitment

Japan NMT (Enmutī) applies strict Japanese quality standards to every 7012 ACE/P4ADGA bearing set – from ring material (high-purity chrome steel) and rolling elements 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 25° contact angle (ACE type), E-type high-speed design, P4A precision, Class A extra light preload, and universal matchable flexibility makes this bearing set the flagship general-purpose precision bearing solution in the NMT 7012 series – offering the perfect balance of high performance, efficient lubrication, and flexible arrangement.

 

Choose NMT 7012 ACE/P4ADGA for:

 

✅ E-type high-speed design – 33,000 r/min ultra-high speed and heavy load combined

 

✅ 25° contact angle – superior combined radial and axial load capacity

 

✅ Universal matchable – one inventory, infinite arrangements

 

✅ Class A extra light preload – ideal for high-speed precision applications

 

✅ P4A super-precision running accuracy

 

✅ All-steel – high rigidity, impact resistance, cost-effectiveness

 

✅ Factory pre-lubricated – ready to install