1 Complete Model & Code Explanation

Model: 7016 ACDGA/P4AL

Code Definition

7016: Basic dimension of 70 series light-duty single-row angular contact ball bearing

ACD: 15° nominal contact angle, machined solid brass cage, optimized for high speed and radial load capacity

GA: Single independent bearing specification with finely machined end faces, no factory duplex matching mark, cannot be used as fixed set directly

P4AL: ISO P4 precision grade, upgraded single-unit tolerance standard with enhanced screening on end face parallelism, suitable for assembly with precision spacers

Supply form: Single independent bearing unit without matching serial number, various combinations can be realized by matching spacers

Important reminder: This model is single independent bearing without factory duplex lapping. Direct assembly of two same bearings cannot guarantee uniform preload. Precision spacers with necessary lapping adjustment are mandatory if stable matching accuracy is required.

Suffix Comparison within Series

7016 ACD/P4A: Basic single bearing P4 precision, standard end grinding

7016 ACDGA/P4AL: Single bearing P4AL precision, enhanced end face parallelism screening (this model)

7016 ACD/P4AQBCC: Factory DB duplex lapped matched bearing set

7016 CE GA/P4AL: 25° contact angle single bearing with upgraded end face P4AL precision

7016 ACD/HC GA/P4AL: 15° contact angle single bearing with hybrid ceramic balls, P4AL grade

Core Basic Dimensions

Bore d: 80 mm

Outer diameter D: 125 mm

Width B: 22 mm

Structure: Single-row open-type angular contact ball bearing, supplied as single unit

Rolling element: High-carbon chromium bearing steel balls (all steel construction)

Ring material: High-carbon chromium bearing steel, ultra-precision mirror grinding on raceway

Cage: Machined solid brass cage

Outer ring feature: Standard plain outer ring without integrated oil-air lubrication grooves

Pre-filled lubricant: None

Delivery form: Individually packed single bearing, no matching serial number

Note: Official dynamic load rating and limiting DN data can be requested from manufacturer.

Full Product Attributes

Contact form: Two-point contact

Number of rows: Single row, single unit without factory duplex matching

Pairing property: No factory end-face duplex lapping; customers can assemble DB/DF/DT combinations with self-prepared precision spacers

Precision class: P4AL single unit with enhanced end-face P4 super precision high-speed grade

Material: Inner & outer rings + rolling elements: high-carbon chromium bearing steel (all steel construction)

Seal structure: Open type, non-sealed

Special construction: High-precision ground end faces with upgraded parallelism indicators, optimized for spacer assembly

Note: The 15° contact angle of ACD delivers higher limiting speed and stronger radial rigidity compared with 25° CE model, while axial load capacity is lower. It fits operating conditions dominated by radial load requiring high rotating speed. Compared with basic P4A single bearings, P4AL tightens control standard of end face parallelism, achieving more uniform stress distribution after assembling with spacers. Open design is recommended to match oil-air lubrication or circulating oil lubrication. Long-term continuous high-speed grease lubrication is not advised. Single unit scheme provides excellent flexibility, ideal for non-standard spindles, multi-bearing layout and equipment requiring customized preload.

2 Structure & Operating Characteristics

Japan NMT 7016 ACDGA/P4AL is single-row open-type all-steel super precision angular contact ball bearing of 7016 series with 15° contact angle. Inner and outer rings adopt stabilized heat treatment to eliminate residual stress and reduce dimensional deformation risk during long-term operation. Raceways are processed via multi-stage ultra-precision mirror grinding with strictly controlled surface roughness to realize low vibration and stable rotational accuracy.

High-precision graded all-steel rolling elements ensure even load distribution. Machined solid brass cage maintains stable dimension under high temperature, offers good impact resistance and anti-creep performance, suitable for long-time continuous cutting of CNC equipment.

The bearing adopts open non-sealed design to avoid frictional heat from sealing components. Plain standard outer ring adapts to spindles equipped with built-in housing oil channels. As an independent single unit, spindle manufacturers can select DB back-to-back, DF face-to-face, DT tandem arrangement according to structural demands, and adjust preload magnitude via precision spacers to satisfy diversified spindle design solutions.

3 Core Performance Advantages

1. ACD 15° small contact angle: Excellent limiting speed and outstanding radial rigidity, applicable for high-speed light to medium radial cutting conditions.

2. P4AL enhanced end-face single unit precision: Upgraded screening standard for end face parallelism, more uniform force distribution when assembled with spacers and less local stress concentration.

3. Flexible single unit combination: No fixed matching limitation, freely form DB, DF, DT assemblies to adapt non-standard spindles and multi-section bearing layout.

4. Machined solid brass cage: Good heat and wear resistance, excellent dimensional stability under long-term high-speed continuous operation.

5. Open non-sealed construction: Eliminates seal friction loss, fully compatible with oil-air forced lubrication and circulating oil cooling lubrication systems.

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

P4AL super precision single bearings are suggested to be assembled in constant-temperature dust-free clean workshops. Fully remove burrs, metal chips and contaminants on shaft and housing surfaces. Controlled thermal mounting method is recommended; open-flame heating or direct striking of bearing rings are forbidden to prevent indentation and early fatigue failure.

Important reminder: This is independent single bearing without factory matching grinding. Direct butt assembly of two bearings is prohibited. Precision spacers of corresponding precision grade are required; spacer end lapping is necessary to guarantee uniform preload.

5.2 Assembly Combination & Preload Instructions

Supply status: Individually packed single bearing without matching serial number, flexible for combination

Optional layout: DB back-to-back / DF face-to-face / DT tandem

Selection tips:

Prioritize ACD 15° series for maximum rotating speed and radial load dominated conditions;

Select CE 25° contact angle series for heavy axial cutting load and higher axial rigidity;

Choose P4AQBCC factory matched bearing set for mass-produced standard spindles to simplify assembly and skip spacer lapping;

Prefer this model ACDGA/P4AL single bearing for non-standard design, prototype development, multi-bearing layout and independent preload adjustment.

Selection reference:

① Basic single unit, 15°, all steel balls, standard P4 →7016 ACD/P4A

② Single unit, 15°, all steel balls, enhanced end face P4AL (this model) →7016 ACDGA/P4AL

③ Factory DB duplex matched set, 15°, all steel balls →7016 ACD/P4AQBCC

④ Single unit, 25°, all steel balls, enhanced end face P4AL →7016 CE GA/P4AL

⑤ Single unit, 15°, hybrid ceramic balls, enhanced end face P4AL →7016 ACD/HC GA/P4AL

5.3 Lubrication Matching Scheme

No pre-filled grease inside bearing. Oil-air forced circulation lubrication is first choice; circulating oil cooling lubrication is also acceptable. Long-duration continuous high-speed grease lubrication is not recommended. Install high-precision filters on lubrication pipelines, hard impurities can easily scratch mirror raceway surfaces. Mixing lubricants of different brands or base oil types is prohibited. Replace filter elements regularly to keep lubricant clean and extend bearing service life.

5.4 Speed Parameter Note

ACD 15° contact angle design naturally adapts to high-speed applications, achieving higher continuous operating speed than 25° contact angle bearings of identical dimension. The whole machine should be equipped with sufficient cooling system and adequate speed safety margin. Open bearings have no built-in dust and cutting fluid resistance. Bearing housing must be equipped with complete external sealing structure to prevent abrasive wear caused by intrusion of dust and emulsion.

6 Daily Maintenance & Fault Troubleshooting

After bearing assembly, carry out multi-stage low-speed running-in, continuously monitor temperature rise and vibration data. Increase rotating speed to rated value only after all indicators stabilize. Focus on temperature variation during running-in period. Regularly inspect housing sealing status, lubrication pipeline pressure and flow rate to ensure stable oil supply.

When persistent abnormal noise, rapid temperature rise or increasing vibration occurs, check sequentially: lubricant cleanliness, coaxiality of shaft and housing, excessive preload force, parallelism of spacer end faces, external impact load, dust or cutting fluid entering bearing interior.

Common failure modes of precision single angular contact bearings include raceway fatigue spalling, abrasive wear caused by foreign particles, overheating seizure due to insufficient lubrication, edge loading from misalignment, accelerated fatigue under excessive preload, uneven force induced by low-precision spacers. Build regular monitoring system for temperature and vibration to detect early damage and avoid unexpected spindle shutdown.