1 Complete Model & Code Explanation

Model: 7012 CDGB/P4A

Code Definition

7012: Light series precision angular contact ball bearing basic dimension

CD: 15° contact angle, small contact angle design for ultra-high limiting speed

GB: Premium Single Sorting, each bearing individually inspected for face height and clearance, ready for flexible on-site matching

P4A: P4A ultra-precision grade

Note: CD(15° high speed)＜CE(18° balanced)＜ACE(25° heavy axial load); GB = single selected unit for field assembly; DBB = factory pre-matched set; HC means hybrid ceramic insulated type, no HC stands for all steel bearing; Distinguished from 7012 CDGB/HCP4A (hybrid ceramic version)

Key Dimensions

Bore d: 60 mm

Outer diameter D: 95 mm

Width B: 18 mm

Contact angle: 15°

Structure: Single row open bearing, supplied as single GB selected unit

Rolling element: High-carbon chromium steel ball

Ring material: High-carbon chromium bearing steel with ultra-precision mirror grinding

Supply form: Single GB selected bearing, customers can assemble DB/DF/DT arrangement on site according to demands

Pre-filled lubricant: None

Coating: None

Note: Contact SKF for official load ratings and limiting speed data.

Full Product Attributes

Contact form: two-point contact

Number of rows: single row single bearing

Matching mode: Individually GB sorted unit, flexible for on-site DB/DF/DT combination

Precision class: P4A ultra-precision grade

Material: All-steel precision bearing (steel rings + steel rolling elements)

Seal: Open type, no seal

Note: The 15° CD small contact angle reduces rolling resistance and delivers excellent limiting DN speed, suitable for long-term high-speed light & medium load applications. Axial rigidity and overturn resistance are inferior to large contact angle ACE series.

This all-steel bearing has no electrical insulation property. It is not recommended for built-in motor spindles with shaft current, and is preferred for belt-driven spindles.

GB premium sorting means each bearing is independently screened on face height and clearance. Users can flexibly configure back-to-back DB, face-to-face DF or tandem DT layout, more flexible than fixed factory pre-matched DBB sets. Open structure eliminates seal drag; continuous oil-air lubrication is mandatory. Long-term high-speed operation with grease is not recommended. No built-in dust shield; labyrinth or air curtain dust-proof device must be equipped.

2 Structure & Operating Characteristics

Japan NMT 7012 CDGB/P4A is size 7012 ultra-precision all-steel single angular contact ball bearing with 15° contact angle and GB premium sorting. Inner/outer rings and steel balls are made of high-carbon chromium bearing steel with mirror ultra-precision grinding. Every single bearing is independently sorted to control face height and clearance range for stable batch consistency.

The 15° small contact angle geometry generates low heat at high speed with outstanding limiting speed. Compared with hybrid ceramic bearings of the same size, it provides better cost performance, widely used in belt-driven high-speed engraving milling and machining center spindles without shaft current risk.

3 Core Performance Advantages

1. 15° CD small contact angle: Low friction loss, excellent limiting DN speed, suitable for long-term continuous high-speed operation.

2. P4A ultra-precision grade: Superior dimensional and rotational accuracy to minimize spindle runout under high RPM.

3. GB single sorting + open construction: Freely combinable DB/DF/DT; eliminates seal friction loss, ideal for oil-air lubricated high-speed spindles.

4. Mature all-steel design: Stable and reliable material, prominent cost advantage for belt-driven applications without shaft current.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

P4A ultra-precision all-steel bearing should be assembled in constant-temperature dust-free clean environment. Remove all burrs, dust and metal debris on shaft and housing mating surfaces. Adopt controlled thermal mounting and limit heating temperature; never strike the bearing to avoid permanent raceway damage. Assemble bearings from the same production batch preferentially.

5.2 Matching & Preload Instructions

Supplied as independent GB selected single bearings without fixed pairing relation; DB, DF, DT arrangement can be configured on site. Select layout based on spindle maximum speed and load; light preload is recommended for high-speed applications, accurately adjusted via spacers. ⚠️Heavy preload is forbidden under ultra-high speed conditions to prevent thermal seizure.

Selection guide: ①Built-in motor spindle with shaft current →hybrid ceramic type 7012 CDGB/HCP4A; ②Continuous high-temperature machining environment →high-temperature series 7012 CDGATP/P4B; ③Heavy cutting requiring high axial rigidity →7012 ACE series; ④Ready-to-use factory matched set →7012 CDGB/P4A DBB.

5.3 Lubrication Matching Solutions

No pre-filled lubricant. Oil-air forced circulation lubrication is mandatory for long continuous high-speed operation. Special high-speed spindle grease is only allowed for short intermittent low-speed operation. Install high-precision filters on oil circuit and strictly control lubricant cleanliness; do not mix lubricants of different brands.

5.4 Speed Parameter Note

Excellent limiting DN value. Sufficient safety speed margin must be reserved under continuous heavy load; avoid prolonged operation near limiting speed.

6 Daily Maintenance & Fault Troubleshooting

Carry out multi-stage low-speed extended running-in after assembly; gradually raise to working speed only after temperature and vibration stay stable. Open bearings have no built-in dust shield; front spindle dust sealing cannot be omitted.

Maintain continuous supply of clean lubricant and avoid dry friction without oil. In case of abnormal heating, continuous noise or sharp vibration increase, sequentially check: oil supply & lubricant cleanliness, excessive preload, assembly coaxiality, dust seal integrity and cutting overload.