1 Complete Model & Code Explanation

Model: 7012 FE/HCP4AH1DGA

Code Definition

7012: Light series precision angular contact ball bearing basic dimension

FE: 21° contact angle, medium-heavy load design between 18° CE and 25° ACE, balancing axial load and high-speed capability

HC: Hybrid Ceramic, silicon nitride ceramic balls + steel inner & outer rings

P4A: P4A ultra-precision grade

H1: Special wear-resistant anti-scuff coating on raceways to improve seizure resistance under boundary lubrication

DGA: GA General Selected sorting grade with controlled face height deviation, standard selected single unit

Note: CD(15° high speed)＜CE(18° balanced)＜FE(21° medium-heavy load)＜ACE(25° heavy axial load); GA general selected ＜ GB premium selected; H1 = raceway functional coating; HC = insulated hybrid ceramic, non-HC = all steel bearing; Comparative models:7012 CE/HCP4A (18° ceramic without coating),7012 ACE/HCP4A (25° heavy-duty ceramic)

Key Dimensions

Bore d: 60 mm

Outer diameter D: 95 mm

Width B: 18 mm

Contact angle: 21°

Structure: Single row open bearing, supplied as single DGA (GA general selected) unit

Rolling element: Silicon nitride (Si₃N₄) ceramic ball

Ring material: High-carbon chromium bearing steel with H1 wear-resistant coating on inner & outer raceways, ultra-precision mirror grinding

Supply form: Single independent bearing, DB/DF/DT arrangement configurable on site

Pre-filled lubricant: None

Surface treatment: H1 functional coating on raceways, no coating on rolling elements

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: GA general selected unit, freely combinable DB/DF/DT on site

Precision class: P4A ultra-precision grade

Material: Hybrid ceramic bearing (H1 coated steel rings + silicon nitride ceramic rolling elements)

Seal: Open type, no seal

Note: The 21° FE contact angle delivers higher axial load capacity than 18° CE series and better limiting speed than 25° ACE heavy-load series, ideal for alternating heavy milling and continuous high-speed finishing. HC ceramic rolling elements provide insulation to block shaft current and avoid raceway electric corrosion. H1 raceway coating greatly improves wear resistance under start-stop and fluctuating load boundary lubrication conditions, reducing micro-scuffing risk. GA selected batch controls face height deviation for easy pairing, more cost-effective than GB premium selected version.

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 structure must be equipped.

2 Structure & Operating Characteristics

Japan NMT 7012 FE/HCP4AH1DGA is size 7012 ultra-precision hybrid ceramic single angular contact ball bearing with 21° contact angle, H1 raceway coating and GA selected grade. Inner & outer raceways are mirror ultra-precision ground and treated with H1 wear-resistant coating; rolling elements adopt silicon nitride ceramic balls. GA sorting reduces batch face height difference. The 21° FE angle creates a balanced window for load and rotational speed, supporting medium-heavy cutting and sustained high-speed operation.

Designed for medium machining centers, large engraving & milling machines, mold high-speed heavy-cut equipment equipped with built-in motor spindles. Suitable for machines with heavy load fluctuation, frequent start-stop, shaft current risk and without willingness to sacrifice excessive maximum speed.

3 Core Performance Advantages

1. 21° FE medium-heavy contact angle: Higher axial load capacity than 18° CE series, superior speed performance versus 25° ACE series, adapts to alternating heavy milling and high-speed finishing.

2. HC hybrid ceramic insulation: Blocks shaft current and prevents electric pitting to extend service life for built-in motor spindles.

3. H1 raceway wear-resistant coating: Enhances anti-scuffing and anti-seizure performance under boundary lubrication, tolerating frequent start-stop and load impact.

4. GA general selected sorting: Controlled face height deviation ensures good consistency during multi-bearing pairing with obvious cost advantages.

5. P4A ultra-precision grade: Excellent rotational accuracy reduces spindle runout and guarantees surface finish for mold curved surface machining.

6. Open non-sealed construction: Zero seal friction loss, fully compatible with oil-air lubrication system for long continuous high-speed operation.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

P4A coated hybrid ceramic ultra-precision bearing shall be assembled in constant-temperature dust-free clean workshop. Remove all burrs, dust and metal debris on shaft and housing mating surfaces. Adopt controlled thermal mounting with limited heating temperature; open flame heating is forbidden. Never strike the bearing; impact may cause ceramic ball chipping, coating peeling and permanent raceway damage. Bearings from the same GA selected batch are preferred for paired assembly.

5.2 Matching & Preload Instructions

Supplied as independent GA selected single bearings without factory pre-matching; DB back-to-back, DF face-to-face, DT tandem layout can be arranged on site. Medium preload is recommended for alternating medium-heavy load conditions. Light preload is suitable for sustained ultra-high speed light cutting. Heavy preload under long-term high-speed running is prohibited to avoid overheating.

Selection guide: ①Pure high-speed light cutting & engraving →15° 7012 CDGB/HCP4A; ②Balanced general medium load →18° 7012 CE/HCP4A; ③Medium-heavy cutting & heavy load fluctuation →7012 FE/HCP4AH1DGA; ④Continuous heavy cutting, rigidity priority →25° ACE series; ⑤Belt spindle without shaft current →corresponding all-steel series.

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 running. Install high-precision filters on oil circuit to maintain lubricant cleanliness; hard contaminants will scratch coating and ceramic ball surfaces. Do not mix lubricants of different brands or specifications.

5.4 Speed Parameter Note

Limiting DN speed is lower than 18° CE hybrid ceramic series and obviously higher than 25° ACE heavy-duty hybrid ceramic bearing. Reserve sufficient speed safety margin under continuous medium-heavy load; avoid prolonged operation near limiting speed.

6 Daily Maintenance & Fault Troubleshooting

Carry out multi-stage low-speed running-in after assembly; gradually increase to rated speed only after temperature rise and vibration stabilize. Open bearings have no built-in dust shield; front spindle dust sealing cannot be omitted.

Maintain continuous supply of clean lubricant to prevent dry friction caused by oil shortage. In case of abnormal heating, continuous noise or sudden vibration change, inspect sequentially: oil supply & lubricant cleanliness, over-limit preload, assembly coaxial accuracy, dust seal condition, cutting load impact. Strictly control impurity content in lubricant to avoid abrasion damage to H1 coating and ceramic rolling elements.