Product Overview

The NMT 7013 ACD/P4A is an open, single-row super-precision angular contact ball bearing. With a 65 mm bore, 100 mm outer diameter, and 18 mm width, this bearing features a 25° contact angle (AC type) and D-type high-capacity design, combined with all-steel rolling elements and a phenolic resin cage. It integrates ultra-high precision, high load capacity, and excellent speed performance into a single package, accommodating radial and unidirectional axial loads simultaneously.

 

The bearing offers a basic dynamic load rating of 39 kN and a static load rating of 35.5 kN. Manufactured to the P4A super-precision tolerance class with bore and OD tolerances controlled within micron-level ranges, the bearing achieves a reference speed of 12,000 r/min under grease lubrication and a limiting speed of 19,000 r/min under oil-air lubrication. The operating temperature range is -30°C to 100°C. The bearing weighs approximately 0.42 – 0.43 kg.

 

Model Code Decoding – Understanding NMT 7013 ACD/P4A

Code Meaning

7013 Basic series designation, 65 mm bore, 100 mm OD

AC Angular contact design with 25° contact angle

D D-type high-capacity design – optimized internal geometry and rolling element parameters for higher load capacity compared to standard designs

P4A Super-precision tolerance class – dimensional accuracy to ISO P4 class (ABEC 7), running accuracy superior to P4

Core Value: The AC-type 25° contact angle delivers superior axial rigidity while maintaining ample radial capacity. The D-type high-capacity design, with optimized rolling element parameters (ball diameter 11.112 mm, 20 balls per bearing), is best suited for heavier loads compared to equivalent B and E type high-speed bearings. P4A super-precision ensures bore and OD tolerances are controlled within micron-level ranges – these three elements work together to make this bearing a high-capacity, ultra-precision general-purpose bearing solution.

 

Core Performance Advantages

1. 25° Contact Angle (AC Type) + D-Type High-Capacity Design – High Load and High Rigidity Combined

The 25° contact angle delivers superior axial rigidity while maintaining ample radial capacity. The D-type high-capacity design, with optimized internal geometry and rolling element parameters (ball diameter 11.112 mm, 20 balls per bearing), achieves an outstanding 39 kN dynamic and 35.5 kN static load rating. It is best suited for heavier loads compared to equivalent B and E type high-speed bearings.

 

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

The P4A tolerance class (dimensional accuracy to ISO P4 class/ABEC 7, running accuracy superior to P4) guarantees minimal radial runout and axial play. Bore and outside diameter tolerances are controlled within micron-level ranges, meeting stringent surface quality and dimensional consistency requirements. Operating temperature range is -30°C to 100°C.

 

3. Excellent Speed Performance

The bearing achieves a reference speed of 12,000 r/min under grease lubrication and a limiting speed of 19,000 r/min under oil-air lubrication. The broad speed range makes it adaptable to applications ranging from general machining to high-speed precision processing.

 

4. 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 19,000 r/min oil-air lubrication limiting speed.

 

5. Open Design – Flexible Lubrication Options

This bearing features an open design with no seals and no lubrication holes, allowing flexible selection of lubrication methods based on application – grease lubrication for general applications, oil-air lubrication for high-speed precision machining.

 

6. Clear Performance Specifications

 

Parameter Value

Bore d 65 mm

Outer Diameter D 100 mm

Width B 18 mm

Contact Angle 25°

Dynamic Load Rating C 39 kN

Static Load Rating C₀ 35.5 kN

Fatigue Load Limit Pu 1.5 kN

Speed (Grease) 12,000 r/min

Speed (Oil-Air) 19,000 r/min

Ball Diameter Dw 11.112 mm

Balls per Bearing 20

Ball Material Bearing Steel

Ring Material Bearing Steel

Cage Material Phenolic Resin

Seal Type Open (Unsealed)

Tolerance Class P4A (ABEC 7)

Preload None (Single Bearing)

Weight 0.42 – 0.43 kg

Temperature Range -30°C to 100°C

Typical Applications

The NMT 7013 ACD/P4A, with its high load capacity, ultra-precision, and excellent speed performance, 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

 

Industrial Pumps and Compressors – high-speed rotating machinery

 

Important Installation Notes

✅ This is a single-row open design bearing – select appropriate lubrication method based on application: grease lubrication for general applications (reference speed 12,000 r/min), oil-air lubrication for high-speed precision machining (limiting speed 19,000 r/min).

 

✅ This is a non-universal matchable single bearing (no G/GA suffix). For paired configurations (DB, DF, DT arrangements), please order the corresponding pre-matched set.

 

⚠️ Ensure shaft and housing fits comply with P4A grade requirements to achieve the expected rotational accuracy and service life.

 

⚠️ A single-row angular contact ball bearing can accommodate axial load in one direction only. Radial loads generate an additional axial force that must be counteracted through paired mounting.

 

⚠️ This bearing has no preload setting – preload must be adjusted during paired installation based on the specific configuration.

 

NMT Quality Commitment

Japan NMT (Enmutī) applies strict Japanese quality standards to every 7013 ACD/P4A bearing – from ring material (high-purity bearing steel) and rolling elements to superfinishing processes. The combination of 25° contact angle (AC type), D-type high-capacity design, P4A super-precision, and phenolic resin cage makes this bearing the flagship general-purpose precision bearing in the NMT 7013 series – offering the perfect balance of high load capacity, ultra-precision, and excellent speed performance.

 

Choose NMT 7013 ACD/P4A for:

 

✅ 25° contact angle + D-type high capacity – 39 kN high load capacity

 

✅ P4A super-precision running accuracy

 

✅ 19,000 r/min oil-air lubrication limiting speed

 

✅ Lightweight phenolic resin cage

 

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

 

✅ Open design – flexible lubrication options