Product Overview

The NMT 7012 FE/HCP4AH1DT is a pre-assembled duplex tandem matched (DT) super-precision hybrid ceramic angular contact ball bearing set, comprising 2 rows of bearings precision-paired in a tandem (<<) 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 an 18° contact angle (FE type) and high-speed E design, combined with silicon nitride (Si₃N₄) hybrid ceramic rolling elements (HC)  and a phenolic resin cage, with two lubrication holes on the thrust side of the outer ring (H1) for efficient oil-air lubrication, specifically optimized for ultra-high-speed rotational applications dominated by heavy unidirectional axial loads.

 

The bearing set offers a radial dynamic load rating of 6,210 lbf (27.6 kN) and a radial static load rating of 5,738 lbf (25.5 kN) . The DT tandem arrangement means both bearings share the same contact angle orientation, with axial loads shared equally across both rows, delivering doubled unidirectional axial load capacity. Manufactured to the P4A super-precision tolerance class with hybrid ceramic technology and H1 efficient lubrication design, the set achieves a limiting speed of 35,000 r/min. The set comes pre-lubricated from the factory – ready to install out of the box. The operating temperature range is -30°C to 110°C.

 

Model Code Decoding – Understanding NMT 7012 FE/HCP4AH1DT

Code Meaning

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

F 18° contact angle design – provides optimized combined radial and axial load capacity

E High-speed E design – offers higher speed capability and can accommodate heavier loads than equivalent B-type high-speed bearings

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

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

H1 Two lubrication holes on the thrust side of the outer ring – facilitates oil-air lubrication directly to the rolling contact zone

DT Duplex Tandem – 2 bearings mounted in the same direction (<<) , doubling unidirectional axial load capacity

Core Value: The DT tandem arrangement means both bearings share the same contact angle orientation, with axial loads shared equally across both rows, enabling extreme unidirectional thrust capacity. The FE-type 18° contact angle balances high speed and high load capacity. The E-type high-speed design offers higher speed capability and can accommodate heavier loads than equivalent B-type designs. HC hybrid ceramic technology drastically reduces centrifugal forces and frictional heat at high speeds. The H1 outer ring lubrication holes facilitate oil-air lubrication directly to the rolling contact zone – these five elements work together to make this bearing set the ultimate solution for heavy-load unidirectional ultra-high-speed spindles. This is a non-universal matchable fixed set – the 2 bearings are factory end-face matched and must not be interchanged or mixed with other bearings.

 

Core Performance Advantages

1. Tandem (DT) Arrangement – Doubled Unidirectional Axial Capacity

With both rows oriented identically, axial load capacity increases by nearly 100% compared to a single bearing. With a dynamic radial load rating of 6,210 lbf (27.6 kN) and static radial load rating of 5,738 lbf (25.5 kN) , this set is ideal for heavy-cutting lathe spindles, powerful drilling spindles, and other unidirectional thrust applications.

 

2. 18° Contact Angle (FE Type) + High-Speed E Design – Ultra-High Speed and Heavy Load Combined

The 18° contact angle delivers superior axial rigidity while maintaining ample radial capacity. The E-type high-speed design offers higher speed capability and can accommodate heavier loads than equivalent B-type high-speed bearings. Combined with hybrid ceramic rolling elements and a phenolic resin cage, the set achieves a limiting speed of 35,000 r/min.

 

3. H1 Outer Ring Lubrication Holes – Maximized Oil-Air Lubrication Efficiency

The H1 suffix indicates two lubrication holes on the thrust side of the outer ring, enabling lubricant to be supplied very close to the ball/raceway contact zone, delivering maximum lubrication and heat dissipation efficiency. This design ensures stable temperature performance even at 35,000 r/min ultra-high speeds, making it particularly suitable for oil-air lubrication systems.

 

4. 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. With 25 ceramic balls per bearing and a 7.938 mm ball diameter, it achieves an excellent balance of low friction and high load capacity. 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, extending bearing service life.

 

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

The P4A tolerance class 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 35,000 r/min limiting speed.

 

7. Clear Performance Specifications

 

Parameter Value

Bore d 60 mm

Outer Diameter D 95 mm

Total Width B 36 mm (2×18 mm)

Contact Angle 18°

Dynamic Radial Load 6,210 lbf (27.6 kN)

Static Radial Load 5,738 lbf (25.5 kN)

Ball Diameter Dw 7.938 mm

Ceramic Balls per Bearing 25

Limiting Speed 35,000 r/min

Ball Material Silicon Nitride (Si₃N₄)

Ring Material Chrome Steel

Cage Material Phenolic

Seal Type Open

Tolerance Class P4A

Arrangement Tandem (<<) DT

Bearings in Set 2

Weight 0.78 kg

Temperature Range -30°C to 110°C

Typical Applications

The NMT 7012 FE/HCP4AH1DT is ideally suited for ultra-high-speed precision equipment where unidirectional axial loads dominate:

 

CNC Lathe Spindles – sustaining continuous axial cutting feed forces

 

Vertical/Horizontal Machining Centers – heavy milling spindles (fixed axial direction)

 

Deep-Hole Drilling Spindles – high-thrust drilling and gun-drilling applications

 

Grinding Machine Wheel Spindles – high-speed rotation under unidirectional grinding forces

 

High-Speed Electric Spindles – precision machining units with constant axial load direction

 

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 is a non-universal matched fixed set (DT) – the 2 bearings are supplied as one complete unit. Do not interchange or mix with other bearings of the same model.

 

⚠️ The tandem arrangement (<<) is directional. Ensure the contact angle direction points toward the incoming axial load – incorrect orientation will eliminate load capacity.

 

✅ This set does not have a preset internal preload. Actual preload must be controlled during installation via locknut torque or precision spacers. Strictly follow NMT's installation guidelines and recommended torque values.

 

✅ To achieve the 35,000 r/min limiting speed, oil-air lubrication is strongly recommended, utilizing the H1 outer ring lubrication holes for maximum efficiency.

 

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

 

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

 

⚠️ Ensure shaft and housing fits comply with P4A grade requirements (bore/OD tolerance -0.004mm to 0).

 

NMT Quality Commitment

Japan NMT (Enmutī) applies stringent end-face parallelism and height-difference matching grinding to every DT tandem set, ensuring load-sharing deviation between the two rows is minimized to an extremely small range. The 7012 FE/HCP4AH1DT delivers P4A accuracy, FE-type 18° contact angle, E-type high-speed design, hybrid ceramic technology, H1 outer ring lubrication holes, and tandem-doubled axial capability for long-lasting, stable rotational support in your heavy-duty unidirectional-load ultra-high-speed spindles.

 

Choose NMT 7012 FE/HCP4AH1DT for:

 

✅ Tandem (DT) arrangement – doubled unidirectional axial capacity

 

✅ FE-type 18° contact angle + E-type high-speed design – 35,000 r/min ultra-high speed and heavy load combined

 

✅ H1 outer ring lubrication holes – maximized oil-air lubrication efficiency

 

✅ Hybrid ceramic technology – a leap in high-speed performance

 

✅ P4A super-precision running accuracy

 

✅ Lightweight phenolic resin cage

 

✅ Factory pre-lubricated – ready to install

 

✅ Reliable choice for heavy-load ultra-high-speed conditions