SET TIMKEN 2MM9318WI DUM PRECISION BALL BEARING 2MM9318WIDUM

Description:

The Timken 2MM9318WIDUM (Manufacturing Part Number: 2MM9318WI DUM, World Part Number: 71918C-T-P4S-DUM) is a matched duplex set of super precision single-row angular contact ball bearings from the Timken Fafnir® 9300WI series. Factory matched with DUM (medium preload), this bearing set is designed for high-speed machine tool spindles requiring exceptional rigidity, low runout, and precise shaft positioning. It is commonly used in CNC machining centers, milling machines, grinding machines, jig borers, and other precision manufacturing equipment.

Applications:

The Timken 2MM9318WIDUM bearing set is engineered for high-speed spindle applications where accuracy, rigidity, and thermal stability are critical. Its duplex medium preload arrangement increases spindle stiffness and improves rotational accuracy, making it ideal for CNC machining centers, high-speed milling machines, precision lathes, grinding machines, machining spindles, and other industrial machine tools.

Technical Specifications:

• Manufacturer Part Number (MPN): 2MM9318WIDUM (Manufacturing Part Number: 2MM9318WI DUM)
• World Part Number: 71918C-T-P4S-DUM
• Manufacturer: Timken Fafnir
• Product Type: Super precision angular contact ball bearing set
• Bearing Type: Duplex matched single-row angular contact ball bearings
• Series: 9300WI (ISO 71918C)
• Bore Diameter (ID): 90 mm
• Outside Diameter (OD): 125 mm (4.921 in)
• Bearing Width (Single): 18 mm (0.709 in)
• Total Width (Duplex Set): 36 mm (1.417 in)
• Contact Angle: 15°
• Arrangement: Duplex matched pair
• Preload: DUM (Medium preload)
• Ball Material: Steel
• Cage Type: CR outer land riding cage
• Cage Material: MBR phenolic cage
• Precision Rating: ISO P4S (ABEC 7/9 equivalent)
• Static Radial Load Rating (C0): 39,200 N (8,810 lbf) per bearing
• ISO Dynamic Radial Load Rating (C1): 40,900 N (9,180 lbf) per bearing
• Limiting Speed (Grease): 12,360 rpm
• Limiting Speed (Oil): 24,720 rpm
• Maximum Shaft Fillet Radius: 1.0 mm (0.039 in)
• Maximum Housing Fillet Radius: 1.0 mm (0.039 in)
• Function: Supports combined radial and axial loads in high-speed precision spindle applications.
• Features: Factory-matched duplex set, medium preload, super precision construction, low runout, high rigidity, optimized for high-speed machine tool spindles, and excellent thermal stability.

Common Replacements:

• Timken 2MM9318WIDUM super precision bearing set
• SKF 71918 CD/P4A duplex bearing set
• NSK 71918CTYNSULP4 duplex bearing set