1 Complete Model, Dimensions, Loads & Technical Parameters

Full Model: 7007 ACD/P4ATBTA

Model Code Explanation

7007: Standard boundary dimension of 70 series precision angular contact ball bearing;

ACD: 25° contact angle, high-load D internal raceway profile;

P4A: P4A ultra-precision tolerance class;

TBTA: 3-bearing set, fixed <>> arrangement, ultra-light preload specification.

Standard Dimension Parameters

Bore d: 35 mm

Outer diameter D: 62 mm

Width B: 42 mm

Contact angle: 25 °

Performance Data

Basic dynamic load rating Cr: 32.5 kN

Basic static load rating C0r: 27 kN

Speed note: Contact SKF for data on achievable rotational speed.

Full Product Attributes

Contact form: standard two-point contact

Number of bearings: 3 (3 single bearings contained in one set)

Ring structure: integrated inner ring and outer ring

Internal design: high-load D optimized design

Compatible re-matching: Not available, factory arrangement fixed

Duplex layout: <>>

Quantity of bearings in kit: 3

Preload specification: ultra-light preload

Tolerance class: P4A precision grade

Material: bearing steel

Coating: uncoated

Seal: open type without seals

Pre-filled lubricant: none, lubrication configured on site

Indicative carbon footprint for new product: 1.7 kg CO₂e

Net weight: 0.45 kg

eClass code: 23-05-08-04

UNSPSC code: 31171531

Note: The 25° contact angle provides excellent axial load capacity. High-load D raceway improves contact stiffness. The triple <>> arrangement is fixed from factory; disassembling, reconfiguring or mixing with other bearings is forbidden. Ultra-light preload reduces heat generation at high speed. Open design requires external dust protection.

2 Structure & Operating Characteristics

Japan NMT 7007 ACD/P4ATBTA is a 7007 size 25° high-load D-type 3-piece precision angular contact bearing set with fixed <>> arrangement, composed of three bearing steel single units from identical batch. Optimized D-shaped raceway enhances contact stiffness, and the 25° contact angle balances radial load and bidirectional axial load capacity.

Open non-sealed construction eliminates seal friction loss and supports oil-air lubrication and high-speed grease lubrication. No lubricant pre-filled; lubricant filling shall be carried out during assembly.

The three bearings are sorted into fixed <>> triple arrangement at factory and cannot be rearranged into DB, DF or pure tandem layout. Adopting ultra-light preload design to suppress temperature rise under high-speed operation, ideal for spindles with continuous high speed and moderate cutting load. All matching parameters are calibrated as a complete set; splitting or mixing with external bearings is prohibited.

3 Core Performance Advantages

1. 25° contact angle + high-load D raceway: Excellent axial load capacity and high contact stiffness.

2. P4A ultra-precision grade: Strict control of rotary runout to maintain long-term spindle accuracy.

3. Factory fixed <>> triple set: No on-site layout adjustment required for direct assembly.

4. Preset ultra-light preload: Lower friction heat, suitable for long-time continuous high-speed operation.

5. Bearing steel material: Outstanding wear resistance and contact fatigue stability.

6. Open seal-free construction, compatible with all kinds of high-speed centralized lubrication systems.

4 Typical Application Scenarios

4.1 High-speed engraving & milling machines, graphite machine precision spindles: Equipment requiring temperature control under long-duration high-speed operation.

4.2 High-speed small cylindrical grinders and precision engraving machine spindles: Rotary supports with medium load, pursuing maximum rotational speed and low heat generation.

4.3 High-speed precision rotary modules for automation equipment: Applications demanding stable bidirectional axial positioning and continuous high-speed operation.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

P4A high-precision bearing sets must be assembled in dust-free clean workshops. Remove all burrs and metal debris on shaft and housing mating surfaces. Controlled thermal mounting is recommended; direct impact on bearing rings and raceways is prohibited. Do not split, reconfigure or mix the set with other bearings; use the complete original <>> triple unit.

5.2 Matching & Preload Instructions

The factory fixed layout is <>> triple arrangement, cannot be converted to back-to-back, face-to-face or pure tandem configuration. Preload level is ultra-light preload. Do not arbitrarily adjust spacers to change preload; full set re-calibration is necessary if preload modification is required.

5.3 Lubrication Matching Solutions

No pre-filled lubricant. Oil-air lubrication is recommended for continuous long-term high-speed operation; dedicated high-speed grease can be used for intermittent working conditions. Do not mix different types or brands of lubricants. Regularly inspect lubrication pipelines.

5.4 Speed Parameter Note

Obtain reference limiting speed data from SKF. Maintain proper safety margin according to working load; moderately reduce operating speed with increased load to control bearing temperature.

6 Daily Maintenance & Fault Troubleshooting

Carry out multi-stage low-speed progressive running-in after assembly. Raise speed to rated value only after temperature rise and vibration stabilize. Open bearings have no dust resistance; the machine must be equipped with labyrinth or contact dust seals.

Ensure continuous and stable lubricant supply to avoid raceway damage caused by dry friction. In case of abnormal temperature rise, increased vibration or noise, sequentially check lubrication supply, mounting coaxiality, preload status and whether actual load exceeds applicable range.