31 mm OD Bearings | McMaster-Carr

Steel balls and washers allow these bearings to handle higher loads than bearings with stainless steel components. With an open design, they dissipate heat more efficiently than one-piece thrust ball bearings.

Bearings with steel cage and with bronze cage handle higher loads and speeds than bearings with a plastic cage.

For technical drawings and 3-D models, click on a part number.

					Thrust Load Cap., lbs.
For Shaft Dia.	OD	Thick.	Cage Material	Washer Material	Dynamic	Static	Max. Speed, rpm	Lubrication	Temp. Range, °F	Includes		Each
Open
15mm	31mm	12mm	Steel	Steel	2,300	3,700	8,500	Required	-40° to 240°	Two Washers	0000000	000000

Crossed-Roller Bearings

With a considerably larger ID than our Face-Mount Crossed-Roller Bearings, use these to run hydraulic lines, electrical wiring, and other components through the inside of the bearing. The rollers face in alternating directions to allow for rigid, accurate motion under any combination of radial, thrust, and moment (twisting) loads. Use in applications where highly accurate motion is necessary, such as machine tools and industrial robots.

Open bearings dissipate heat more efficiently than sealed bearings.

For technical drawings and 3-D models, click on a part number.

				Combined Load Cap., lbs.
For Shaft Dia., mm	For Housing ID, mm	Wd., mm	Ring Material	Dynamic	Static	Max. Speed, rpm	Lubrication	Temp. Range, °F		Each
Open
20	31	5	Steel	310	290	2,900	Required	0° to 230°	0000000	0000000

Needle-Roller Thrust Bearings

Thinner rollers allow these bearings to fit in tighter spaces than tapered-roller thrust bearings. Because of the large contact area between the rollers and washers (not included), these bearings are great for medium to heavy duty, low-friction jobs. For use on hardened and ground surfaces.

Washers allow you to use the bearing on unhardened and unground surfaces.

For technical drawings and 3-D models, click on a part number.

Bearings

Bearing

			Thrust Load Cap., lbs.
For Shaft Dia.	OD	Thick.	Dynamic	Static	Max. Speed, rpm	Lubrication	For Shaft Surface Smoothness (Ra), microns	Temp. Range, °F		Each
Steel Rollers
Open
18mm	31mm	2mm	2,140	5,480	10,000	Required	0.2	0° to 240°	0000000	00000

Washers

Washer

For Shaft Dia.	OD	Thick.	Washer Material		Each
18mm	31mm	1mm	Steel	0000000	00000

Washers for Needle-Roller Thrust Bearings

Washer

Adapt needle-roller thrust bearings to use on unhardened, unground surfaces.

For technical drawings and 3-D models, click on a part number.

For Shaft Dia.	OD	Thick.	Washer Material		Each
18mm	31mm	1mm	Steel	0000000	00000

Linear Bearings for Spline Shafts

With a grooved inner diameter, these bearings are designed to work with splined shafts. Together, they transmit rotary power while allowing the bearing to move freely along the length of the shaft. All are for use where shaft misalignment is unlikely.

Also known as ball splines, ball bearings run with less friction than plain bearings, so they're smoother and more precise, even at high speeds. However, they don't transmit as much torque as plain bearings. They're commonly used for robotic systems and other automated applications that require complex, fast movements. Bearings with stainless steel balls are more corrosion resistant than bearings with steel balls.

For technical drawings and 3-D models, click on a part number.

Steel Ball Bearings

Ball Bearing with Steel Balls

For Four Splines

Fixed Alignment
For No. of Splines	For Shaft Dia., mm	Overall Lg., mm	OD, mm	Max. Torque, in.-lbs.	Max. Temperature, °F		Each
4	16	50	31	531	176°	00000000	000000

Stainless Steel Ball Bearings

Ball Bearing with Stainless Steel Balls

For Four Splines

Fixed Alignment
For No. of Splines	For Shaft Dia., mm	Overall Lg., mm	OD, mm	Max. Torque, in.-lbs.	Max. Temperature, °F		Each
4	16	50	31	531	176°	00000000	0000000

Steel Spline Shafts

Splined on Both Ends

Four Splines

4 Splines
Dia., mm	Lg., mm	Spline Lg., mm	End Type		Each
16	200	200	Splined End × Splined End	000000000	000000
16	500	500	Splined End × Splined End	000000000	000000
16	700	700	Splined End × Splined End	000000000	000000
16	1,000	1,000	Splined End × Splined End	000000000	000000
16	1,500	1,500	Splined End × Splined End	000000000	000000

Mounted Linear Bearings for Spline Shafts

A flanged housing with mounting holes connects these bearings directly to your system. They have a grooved inner diameter that's designed to work with spline shafts. Together, they transmit rotary power while allowing the bearing to move freely along the length of the shaft. Wide and flat, the flange is especially useful for lifting and lowering loads on vertical shafts. All are for use where shaft misalignment is unlikely.

For technical drawings and 3-D models, click on a part number.

Steel Ball Bearings with Steel Housing

Steel Ball Bearing with Steel Housing

For Four Splines

								Mounting Holes
For No. of Splines	For Shaft Dia., mm	Overall Lg., mm	Flange OD, mm	Bolt Circle Dia., mm	OD, mm	Max. Torque, in.-lbs.	Max. Temperature, ° F	No. of	Thread Size		Each
Fixed Alignment
4	16	50	50	40	31	531	176°	4	M4 × 0.7	000000000	000000

Stainless Steel Ball Bearings with Aluminum Housing

For Four Splines

								Mounting Holes
For No. of Splines	For Shaft Dia., mm	Overall Lg., mm	Flange OD, mm	Bolt Circle Dia., mm	OD, mm	Max. Torque, in.-lbs.	Max. Temperature, ° F	No. of	Thread Size		Each
Fixed Alignment
4	16	50	50	40	31	531	176°	4	M4 × 0.7	000000000	0000000

Steel Spline Shafts

Splined on Both Ends

Four Splines

4 Splines
Dia., mm	Lg., mm	Spline Lg., mm	End Type		Each
16	200	200	Splined End × Splined End	000000000	000000
16	500	500	Splined End × Splined End	000000000	000000
16	700	700	Splined End × Splined End	000000000	000000
16	1,000	1,000	Splined End × Splined End	000000000	000000
16	1,500	1,500	Splined End × Splined End	000000000	000000

Metric Press-Fit Drill Bushings

Also known as jig bushings, these metric drill bushings fit inside fixture plate holes to guide drill bits, counterbores, reamers, and other cutting tools. They improve accuracy so that your drilled holes and cuts are consistent from part to part. Known for their versatility, drill bushings are also used as spacers, shims, and machinery bushings. These bushings are made of hardened, ground steel that holds its shape and resists wear, so they last for many cycles without needing to be replaced.

All bushings have a chamfer on the outside that centers the bushing as you place it into the hole. Press into place with a manual or hydraulic press. They also have internal chamfers, so it's easier to insert bits, pins, and punches into the bushing. DIN 179 bushings meet dimensional and material standards that make sure they're compatible with other parts and tools. Although DIN 179 is no longer an active standard, it's still a common reference point for designers.

Don't see the size you need? Additional sizes are available.

For technical drawings and 3-D models, click on a part number.

				Tolerance								Each
OD, mm	Lg., mm	Internal Chamfer	For Drill Bit Size	ID, mm	OD, mm	Lg., mm	Drill Bushing Type	Material	Hardness	Specifications Met		1-5	6-11	12-Up
25 mm ID
31	15	One End	25 mm	0.02 to 0.041	0.017 to 0.033	-0.2 to 0.2	PM	Steel	Rockwell C61	DIN 179	000000000	000000	000000	000000
31	50	One End	25 mm	0.02 to 0.041	0.017 to 0.033	-0.3 to 0.3	PM	Steel	Rockwell C61	DIN 179	000000000	00000	00000	00000
31	60	One End	25 mm	0.02 to 0.041	0.017 to 0.033	-0.3 to 0.3	PM	Steel	Rockwell C61	DIN 179	000000000	00000	00000	00000

About Linear Bearings

About Ball and Roller Bearings

Thrust Ball Bearings

Crossed-Roller Bearings

Needle-Roller Thrust Bearings

Washers for Needle-Roller Thrust Bearings

Linear Bearings for Spline Shafts

Mounted Linear Bearings for Spline Shafts

Metric Press-Fit Drill Bushings