40TAC90BDBC9PN7A bearings ( 40 mm x 90 mm x 20 mm) have the advantages of High axial stiffness and load-bearing capacity, 60° contact angle design, pre-installed and pre-loaded for easy installation, optional sealing for maintenance-free operation, and are therefore widely used in the Machine tool ball screws, machining centers, automated equipment, robots, precision measuring devices.

| Part Number | 40TAC90BDBC9PN7A |
| Bearing Type | High precision Angular Contact Thrust Ball Bearings TAC B Series for Ball Screw Support |
| Application | Machine Tool |
| Interchangeable | NSK 40TAC90BDBC9PN7A |
| Internal design | B |
| Design | TAC |
| Preload | C9 = light preload |
| Arrangement row | Two |
| Series | TAC B series (..TAC..BDBC9PN7A) |
| Rows NO. | One |
| Arrangement | DB = Duplex set (<>) |
| Cage | molded polyamide resin cage |
| Seal | open type |
| Accuracy class | PN7A = ISO Class 4 |
| Recommended Grease Quantities - (cc) | 8.8 g/brg |
| Dimension and weight | |
| Inside - d φ [inch] | 1.5748 |
| Outside - D Φ [inch] | 3.5433 |
| Width - B [inch] | 0.7874 |
| Chamfer - r min [inch] | 0.0394 |
| Chamfer - r1 min [inch] | 0.0236 |
| d1 [inch] | 2.2441 |
| d2 [inch] | 2.6772 |
| D1 [inch] | 2.6772 |
| D2 [inch] | 3.0394 |
| Contact angle - α [°] | 60 |
| DB Bearing Mass - m [lb] | 2.9718 |
| Dynamic Axial DB - Ca [lbf] | 12812 |
| Limiting Axial Load DB [lbf] | 19794 |
| Speed ratings (grease) - nB [min–1] | 2890 |
| Speed ratings (oil) - nG [min–1] | 3921 |
The 40TAC90BDBC9PN7A Ball screw support bearings are typically composed of high-precision angular contact ball bearings paired back-to-back (DB) or in series (DT) configurations. They feature a small contact angle (15° or 20°) and high-rigidity cages (phenolic resin or brass) on both inner and outer rings, achieving a precision grade of P4 or higher. Some models integrate seals and lubrication holes, forming a preload unit.
Ball screw support bearings offer extremely high axial rigidity and load-bearing capacity, accurately withstanding bidirectional axial loads in screw drives. The back-to-back configuration provides anti-overturning moment capability, ensuring positioning accuracy. The preload design eliminates axial backlash, achieving backlash-free, low-friction operation with low heat generation, making them suitable for high-speed feed. They are factory-installed and ready to use, simplifying installation and adjustment.















