# Timken 3MM9121WI SUH Super Precision Angular Contact Ball Bearing, Triplex Set, Medium Preload, ABEC 7 P4S - MROSupply.com

***Timken 3MM9121WI SUH super precision angular contact ball bearing, triplex set with medium preload (SUH). ABEC 7 (P4S) precision class for high-rigidity machine tool spindles, jig borers, and precision grinding applications requiring maximum stiffness and runout control. Triplex configuration provides axial location in both directions.***



## Product details:

- Catalog number: 3MM9121WI SUH
- SKU: 5081561
- Call for Pricing - 888-671-2883
- Shipping: ***FREE SHIPPING***  ON ORDERS OVER $100
- Typically Ships in: 1 day
- Brand: [Timken](https://www.mrosupply.com/brands/timken/)
- Category: 
    - [Single Row Angular Contact Bearings](htts://www.mrosupply.com/bearings/ball-bearings/angular-contact-ball-bearings/single-row-angular-contact-bearings/)
    - [Angular Contact Ball Bearings](htts://www.mrosupply.com/bearings/ball-bearings/angular-contact-ball-bearings/)
    - [Ball Bearings](htts://www.mrosupply.com/bearings/ball-bearings/)
    - [Bearings](htts://www.mrosupply.com/bearings/)
- Unit of measure: each
- Weight: 3.565 lb
- Returns: Yes


## Product images:
- https://static.mrosupply.com/images/noimage.webp


## Product attributes;

  
- 1.0236 in C0 - Static Radial Rating (per row): 84500 N
  

  
- 1.0236 in World part number: 7021E-T-P4S-SUH
  

  
- 18900 lbf Cage type: CR - Phenolic Outer Land Riding Cage Contact angle:25 Design units:Metric Inner ring backing diameter:115.7 mm
  

  
- 19000 lbf C1 ISO - Dynamic Radial Rating (per row): 84000 N
  

  
- 4.560 in Limiting Speed (Grease) (per row): 7100 RPM Limiting speed (oil):14200 rpm Manufacturing part number:3MM9121WI SUH O.D. (in):160 mm 6.2992 Outer ring backing diameter:150 mm
  

  
- 5.910 in Precision rating: ISO P4S (ABEC 7/9) Rows per set:Single Total width:26 mm
  

  
- Ball type: Steel Bearing width:26 mm
  

  
- Ball Type: STEEL
  

  
- Bearing Width: 26 mm 1.0236 in
  

  
- Bore: 105 mm
  

  
- C0 - Static Radial Rating (per row): 84500 N 19000 lbf
  

  
- C1 ISO - Dynamic Radial Rating (per row): 84000 N 18900 lbf
  

  
- Cage Type: CR - Phenolic Outer Land Riding Cage
  

  
- Ce - Dynamic Radial Rating (per row): 92100 N 20700 lbf
  

  
- Contact Angle: 25 º
  

  
- d - Bore: 105 mm
  

  
- D - Outer Diameter: 160 mm 6.2992 in
  

  
- da - Inner Ring Backing Diameter: 115.7 mm 4.560 in
  

  
- Da - Outer Ring Backing Diameter: 150 mm 5.910 in
  

  
- Design Units: Metric
  

  
- DOuter Ring Backing Diameter: 150 mm 5.910 in
  

  
- Dynamic Radial Rating (per row): 92100 N 20700 lbf
  

  
- I.D.: 105 mm
  

  
- Inner Ring 'To Clear' Radius: 2 mm 0.079 in
  

  
- Inner Ring Backing Diameter: 115.7 mm 4.560 in
  

  
- Limiting Speed (Grease) (per row): 7100 rpm
  

  
- Limiting Speed (Oil): 14200 rpm
  

  
- Manufacturing Part Number: 3MM9121WI SUH
  

  
- Outer Diameter: 160 mm 6.2992 in
  

  
- Outer Ring 'To Clear' Radius: 2 mm 0.079 in
  

  
- Precision Rating: ISO P4S (ABEC 7/9)
  

  
- R - Inner Ring "To Clear" Radius: 2 mm 0.079 in
  

  
- r - Outer Ring "To Clear" Radius: 2 mm 0.079 in
  

  
- Rows per Set: Single
  

  
- Static Radial Rating (per row): 84500 N 19000 lbf
  

  
- Total Width: 26 mm 1.0236 in
  

  
- World Part Number: 7021E-T-P4S-SUH
  
## Product documents / software:

- [Catalog](https://documents.mrosupply.com/product_documents/50/60/5060627/Machine-Tool-Applications-Catalog_R9rBZA3.pdf)

## Product's reviews:
- Best company to buy from - I always buy from MRO is a very reliable company to work with




## FAQ:

- How do I choose the right type of bearing for my application?: Start with the load and how it’s applied. You need to know if you’re dealing with radial loads, axial loads, or a mix of both. Then look at speed, operating environment, and space constraints.
For example, ball bearings are great for high speed and lighter loads, while roller bearings handle heavier loads but usually at lower speeds. If there’s contamination, moisture, or heat involved, you may need sealed bearings or specific materials.
In most cases, the right choice comes down to matching load type, speed, and environment to the bearing design.


- What is the difference between deep groove and angular contact ball bearings?: Deep groove ball bearings are the most common type. They’re designed to handle mainly radial loads, but they can also take some axial load in both directions. They’re simple, versatile, and used in everything from motors to conveyors.
Angular contact ball bearings are built for combined loads, especially where there’s significant axial force in one direction. They’re often used in pairs and are common in higher precision or higher load applications like pumps and gearboxes.
If your load is mostly radial, go deep groove. If axial load matters more, angular contact is usually the better choice.