The Ultimate Guide to Reali-Slim Thin Section Bearings

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The Ultimate Guide to Reali-Slim Thin Section Bearings

Reali-Slim thin-section bearings are a shining pearl among industrial bearings and are world-famous for their space and weight savings. This blog will comprehensively introduce the specifications, sealing, tolerances, lubrication, code identification, and how to choose the appropriate bearing for Reali-Slim thin-section bearings, and provide you with constructive suggestions.

Table of Contents

Reali-Slim thin section bearing overview

Kaydon Reali Slim thin section bearings are available in both inch and metric size standards. Inch size Kaydon Reali Slim thin section bearings are available in seven open series and five sealed series, with bore diameters ranging from 1 inch to 40 inches, and cross-sections ranging from 0.187×0 .187 inches to 1×1 inches. Kaydon thin section bearings can provide internal assembly, lubricants, cages and other features to meet the most demanding application requirements. If corrosion resistance is required, Kaydon stainless steel Reali Slim or Endura Slim series bearings are good options. The anti-corrosion performance of Endurakote-coated bearings is better than that of stainless steel bearings. Metric Kaydon also has several series, including Kaydon Reali Slim MM metric series bearings, Ultra Slim bearings, Reali Smim TT series turntable bearings, BB metric ball bearings, KT thin-section tapered bearings, etc.

If the bearing will not be exposed to a polluted environment, you can consider choosing an open bearing. If the bearing needs to be kept clean and well lubricated, you can choose a sealed bearing. To support various load conditions, Kaydon Reali Slim bearings are available in three basic types, radial contact (Type C), angular contact (Type A) and four-point contact (Type KC, etc.) Kaydon Reali Slim bearings are available with a variety of cage options to evenly space rolling elements and prevent contact between them. Available cage types include continuous ring “sleeve cages”, continuous ring circular cages, Molded cage, ring cage, PTFE cage, etc.

Specifications of Reali-Slim thin section bearings

The specifications of Reali-Slim thin-section bearings are extremely important for the traceability of bearing products. Specification control charts provide users with the characteristics and parameters of a specific bearing, as well as the ability to generate unique numbers and other options for the bearing. This allows you to identify bearings quickly and easily. Each series of Reali-Slim bearings is based on a cross-section that remains constant as the bearing’s bore diameter increases. The constant cross-section of Reali-Slim bearings is of particular value when designing products that will be manufactured in various sizes depending on shaft diameter and power requirements. Kaydon Reali-Slim® bearings can be optimized for specific applications and custom manufactured with non-standard materials, dimensions, tolerances, properties, and custom packaging and lubrication options. Standard commercial options include diameter clearance variations, preload, lubricants, packaging, high-point etching, and .

tem	Description	Reference specification
Material analysis
Races & balls	SAE-AISI 52100 type steel AISI 440C stainless steel	ASTM A-295 AMS-5630
Separators A bearings	R type—brass or non-metallic composite G type—nylon, fiberglass reinforced	ASTM B-36
Separators C, X bearings	P type—brass or non-metallic composite L type—nylon, fiberglass reinforced	ASTM B-36
Seals	Nitrile rubber
Heat treatment
Races & balls	Through hardened and dimensionally stabilized for use from -65°F to +250°F (-54°C to +121°C)
Precision
Race dimension	Kaydon Precision Class 1	ABMA ABEC-1F or better, per ABMA Standard 26.2
Race runouts	Kaydon Precision Class 1	ABMA ABEC-1F or better, per ABMA Standard 26.2
Balls	ABMA grade 10	ANSI/ABMA/ISO 3290
Diametral clearance & contact angle
Type A bearing	Diametral clearance for 30° contact angle in single unmounted bearing under light axial gaging load. Wide range of preload or running clearance for matched sets.
Type C bearing	Sufficient diametral clearance to provide small amount of running clearance after installation with recommended fits.
Type X bearing	Gothic arch form for two 30° contact angles under light radial gaging load. Sufficient diametral clearance to provide clearance after installation with recommended fits.
Separator design
R & G types A bearings	Circular ring, circular pockets, self retained
P & L types C, X bearings	Circular ring, snapped over balls for retention
Other
Quality control	Kaydon Quality Control procedures have been approved by major aerospace industries and agencies of the U.S. Government	ISO 9001, AS 9100
Identification	Marked on bearing O.D.: CAGE code, “Kaydon”®, part number and date code	MIL-STD-130
Cleaning	Multiple cycle immersion and agitation in solvents and/or aqueous cleaners
Preservative	Preservative oil
Packaging	Typically, smaller bearings are heat-sealed in a plastic bag and boxed; larger bearings are “tire-wrapped.”

Ultra-thin Reali-Slim bearings

Ultra-thin Reali-Slim bearings bring additional advantages in application design. The ultra-thin Reali-Slim bearings with large bore diameter and small cross-section allow the use of large diameter hollow shafts instead of small diameter solid shaft, main column designs. Components such as air and hydraulic lines or electrical wires and slip rings can then be accommodated within the hollow shaft, resulting in a cleaner, efficient design. In many applications, a single four-point contact Reali-Slim bearing can replace two bearings, shrinking the design and simplifying bearing installation. In addition to the obvious cost savings of eliminating one bearing, this arrangement creates space and reduces weight. The use of Reali-Slim bearings also provides a stronger structure by using a large diameter hollow tube instead of a solid shaft and supporting the rotating structure (table) on the periphery.

Reali-Slim Thin Section Bearing Code Identification

Position	1	2	3	4	5	6	7	8	9	10-13
Nomenclature	Material	Series	Size			Type	Separator	Precision	Internal fit	DFAR compliance
Example	J	B	0	2	0	C	P	0		-USA

Position 1—Material

Position 1—Material
Races/balls	Seals, shields
A	AISI 52100 Steel	One seal—PTFE
B	AISI 52100 Steel	Two seals—PTFE
D	AISI 52100 Steel	One shield
E	AISI 52100 Steel	Two shields
F	AISI 52100 Steel	One seal—Nitrile rubber Lami-seal®
G	AISI 52100 Steel	Two seals—Nitrile rubber Lami-seal®
H	AISI 52100 Steel	One seal—Nitrile rubber
J	AISI 52100 Steel	Two seals—Nitrile rubber
K	AISI 52100 Steel	No seals or shields
L	AISI 52100 Steel	Two seals & Endurakote® plating
M	M-50 Steel	No seals or shields
N	AISI 52100 Steel	No seals & Endurakote® plating
P	AISI 17-4PH Steel	Ceramic balls
Q	AISI 52100 Steel	No shields or seals
S	AISI 440C Stainless Steel	No seals or shields
T	AISI 440C Stainless Steel	One seal—PTFE
U	AISI 440C Stainless Steel	Two seals—PTFE
V	AISI 440C Stainless Steel	Two shields
W	AISI 440C Stainless Steel	Two seals—Nitrile rubber
X	AISI 52100 Steel	Ceramic balls
Y	AISI 440C Stainless Steel	Ceramic balls
Z	Other

Position 2—Standard series cross section (inches)

	Open bearings
			Radial thickness				Width
	AA		*.187			x	.187
	A		.250			x	.250
	B		.312			x	.312
	C		.375			x	.375
	D		.500			x	.500
	F		.750			x	.750
	G		1.000			x	1.000
Sealed bearings
		Radial thickness			Width
JHA		.187		x	.250
JA		.250		x	.250
JB		.312		x	.312
JU		.500		x	.375
JG		1.000		x	1.000
* Smaller section applies when position 3 is alphabetic—see following explanations of positions 3, 4, and 5.

Positions 3, 4, & 5—Size (bearing bore)

Numeric characters
Nominal bearing bore in inches multiplied by ten

Alphabetic characters
“A” in position 3 in combination with “A” in position 2
denotes .187 x .187 series
“A” in position 3 in combination with “H” in position 2
denotes .187 x .250 series
“A” in position 3 in combination with “S” in position 2
denotes .187 x .312 series

Examples
040 = 4.0″ bore
120 = 12.0″ bore
400 = 40.0″ bore
“10” following “AA” in positions 2 & 3 =
.187 x .187 series with 1.0″ bore
“15” following “HA” in positions 2 & 3 =
.187 x .250 series with 1.5″ bore

Position 6—Bearing type

A	Angular contact single bearing (not ground for universal duplexing)
B	Angular contact pair—duplexed back to back
C	Radial contact
F	Angular contact pair—duplexed face to face
T	Angular contact pair—duplexed tandem
U	Angular contact single bearing—ground for universal duplexing
X	Four-point contact
Z	Other

Position 7—Separator


C	Non-metallic composite, segmental, “snap-over” type
D	Phenolic laminate, one-piece ring “snap-over” type
E	Brass, segmental “snap-over” type
L	Nylon, one-piece ring “snap-over” type
N	Nylon, “snap-over” type
P	Standard formed ring “snap-over” type (material—brass or non-metallic composite)
T	Stainless steel, formed ring “snap-over” type
V	Brass, formed ring, “snap-over” type
X	PEEK, one-piece, “snap-over” pocket

G	Nylon one-piece ring, circular pocket
H	Phenolic laminate, one-piece ring with circular pockets
J	Nylon strip separator, circular pockets
K	Phenolic laminate, riveted two-piece ring
Q	PEEK, one-piece ring, circular pocket
R	Standard formed ring, circular pocket (material—brass or non-metallic composite)
U	Stainless steel, formed ring circular pockets
Y	Brass, formed ring, circular pockets

M	Formed wire, strip or segmental, “snap-over” type, ball in every pocket
W	Formed wire, strip or segmental, “snap-over” type

F	Full complement bearing—no separator
S	Helical coil springs
Z	Other (toroids, slugs, spacer balls or others available)

Position 8—Precision

(ABEC specifications are per ABMA standard 26.2)
0	Kaydon precision class 1 per ABEC 1F
1	Kaydon precision class 1 with class 4 runouts
2	Kaydon precision class 1 with class 6 runouts
3	Kaydon precision class 3 per ABEC 3F
4	Kaydon precision class 4 per ABEC 5F
6	Kaydon precision class 6 per ABEC 7F
8	Other

Position 9—Bearing internal fit

A	.0000 to .0005 clearance
B	.0000 to .0010 clearance
C	.0005 to .0010 clearance
D	.0005 to .0015 clearance
E	.0010 to .0020 clearance
F	.0015 to .0025 clearance
G	.0020 to .0030 clearance
H	.0030 to .0040 clearance
I	.0040 to .0050 clearance
J	.0050 to .0060 clearance
K	.0000 to .0005 preload
L	.0000 to .0010 preload
M	.0005 to .0010 preload
N	.0005 to .0015 preload
P	.0010 to .0020 preload
Q	.0010 to .0015 preload
R	.0015 to .0025 preload
S	.0020 to .0030 preload
Z	Other clearance or preload not specified above
Type X or C = diametral preload or clearance Duplexed type A = axial preload or clearance Note: Above internal bearing fits apply to unmounted bearings only. Mounting fits can greatly affect final internal bearing fit.

Position 10–13—DFAR compliance

All Reali-Slim® bearings requiring compliance with Defense Federal Acquisition Regulations (DFAR) “Specialty Metals” and “the Restrictions on Acquisition of Ball and Roller Bearings” clauses will contain ‘-USA’ in positions 10-13. If internal fit is not called out in position 9, it will also contain a dash.

Example #1: KG120XP0L-USA
Example #2: KG120XP0–USA

KAYDON thin section bearing precision tolerances

KAYDON type C thin section bearing, Precision class 1 (Ref. ABEC 1F)

Bearing size (inch series)	Bearing diameters		Radial & Axial runout		Rotating Shaftor Duplex DF Mounting		Stationary Shaftor Duplex DB Mounting				Bearing Diametral clearance* before installation
Bearing size (inch series)	Bearing Bore Nominal	Bearing O.D. Nominal	Inner Race	Outer Race	Shaft Diameter Nominal	Housing Bore Nominal	Shaft Diameter Nominal		Housing Bore Nominal		Bearing Diametral clearance* before installation
010	-0.0004	-0.0005	0.0005	0.0008	0.0004	0.0005	-0.0004	-0.0008	-0.0005	-0.001	0.001	0.0016
015	-0.0005	-0.0005	0.0006	0.0008	0.0005	0.0005	-0.0005	-0.001	-0.0005	-0.001	0.0012	0.0018
017	-0.0006	-0.0005	0.0008	0.001	0.0006	0.0005	-0.0006	-0.0012	-0.0005	-0.001	0.0012	0.0024
020	-0.0006	-0.0005	0.0008	0.001	0.0006	0.0005	-0.0006	-0.0012	-0.0005	-0.001	0.0012	0.0024
025	-0.0006	-0.0005	0.0008	0.001	0.0006	0.0005	-0.0006	-0.0012	-0.0005	-0.001	0.0012	0.0024
030	-0.0006	-0.0006	0.0008	0.001	0.0006	0.0006	-0.0006	-0.0012	-0.0006	-0.0012	0.0012	0.0024
035	-0.0008	-0.0006	0.001	0.0012	0.0008	0.0006	-0.0008	-0.0016	-0.0006	-0.0012	0.0016	0.0028
040	-0.0008	-0.0006	0.001	0.0012	0.0008	0.0006	-0.0008	-0.0016	-0.0006	-0.0012	0.0016	0.0028
042	-0.0008	-0.0008	0.001	0.0014	0.0008	0.0008	-0.0008	-0.0016	-0.0008	-0.0016	0.0016	0.0028
045	-0.0008	-0.0008	0.001	0.0014	0.0008	0.0008	-0.0008	-0.0016	-0.0008	-0.0016	0.0016	0.0028
047	-0.001	-0.0008	0.0012	0.0014	0.001	0.0008	-0.001	-0.002	-0.0008	-0.0016	0.002	0.0034
050	-0.001	-0.0008	0.0012	0.0014	0.001	0.0008	-0.001	-0.002	-0.0008	-0.0016	0.002	0.0034
055	-0.001	-0.001	0.0012	0.0016	0.001	0.001	-0.001	-0.002	-0.001	-0.002	0.002	0.0034
060	-0.001	-0.001	0.0012	0.0016	0.001	0.001	-0.001	-0.002	-0.001	-0.002	0.002	0.0034
065	-0.001	-0.001	0.0012	0.0016	0.001	0.001	-0.001	-0.002	-0.001	-0.002	0.002	0.0034
070	-0.001	-0.0012	0.0012	0.0016	0.001	0.0012	-0.001	-0.002	-0.0012	-0.0024	0.0024	0.0042
075	-0.0012	-0.0012	0.0016	0.0018	0.0012	0.0012	-0.0012	-0.0024	-0.0012	-0.0024	0.0024	0.0042
080	-0.0012	-0.0012	0.0016	0.0018	0.0012	0.0012	-0.0012	-0.0024	-0.0012	-0.0024	0.0024	0.0042
090	-0.0012	-0.0012	0.0016	0.0018	0.0012	0.0012	-0.0012	-0.0024	-0.0012	-0.0024	0.0024	0.0042
100	-0.0014	-0.0014	0.0018	0.002	0.0014	0.0014	-0.0014	-0.0028	-0.0014	-0.0028	0.0028	0.0048
110	-0.0014	-0.0014	0.0018	0.002	0.0014	0.0014	-0.0014	-0.0028	-0.0014	-0.0028	0.0028	0.0048
120	-0.0014	-0.0014	0.0018	0.002	0.0014	0.0014	-0.0014	-0.0028	-0.0014	-0.0028	0.0028	0.0048
140	-0.0016	-0.0016	0.0018	0.002	0.0016	0.0016	-0.0016	-0.0032	-0.0016	-0.0032	0.0032	0.0052
160	-0.0018	-0.0018	0.0018	0.002	0.0018	0.0018	-0.0018	-0.0036	-0.0018	-0.0036	0.0036	0.0056
180	-0.0018	-0.0018	0.002	0.002	0.0018	0.0018	-0.0018	-0.0036	-0.0018	-0.0036	0.0036	0.0056
200	-0.002	-0.002	0.002	0.002	0.002	0.002	-0.002	-0.004	-0.002	-0.004	0.004	0.006
210	-0.002	-0.002	0.002	0.002	0.002	0.002	-0.002	-0.004	-0.002	-0.004	0.004	0.006
220	-0.002	-0.002	0.002	0.002	0.002	0.002	-0.002	-0.004	-0.002	-0.004	0.004	0.006
250	-0.003	-0.003	0.002	0.002	0.003	0.003	-0.003	-0.006	-0.003	-0.006	0.006	0.008
300	-0.003	-0.003	0.002	0.002	0.003	0.003	-0.003	-0.006	-0.003	-0.006	0.006	0.008
350	-0.004	-0.004	0.002	0.002	0.004	0.004	-0.004	-0.008	-0.004	-0.008	0.008	0.01
400	-0.004	-0.004	0.002	0.002	0.004	0.004	-0.004	-0.008	-0.004	-0.008	0.008	0.01

*Diametral clearance after installation theoretically can range rather widely if all contributing bearing, housing, and shaft tolerances are at either of their extremes.

Listed shaft and housing diameters are for steel supports with standard bearing diametral clearance. Recommended shaft and housing diameters can change greatly based on orientation, temperature, speed, non-standard diametral clearances, and desired performance characteristics. Contact Kaydon for design assistance when required.

KAYDON type A thin section bearing, Precision class 1 (Ref. ABEC 1F)

Kaydon Bearing size (inch series)	Bearing diameters		Radial & Axial runout		Rotating Shaftor Duplex DF Mounting		Stationary Shaftor Duplex DB Mounting				Bearing Diametral clearance* before installation
Kaydon Bearing size (inch series)	Bearing Bore Nominal	Bearing O.D. Nominal	Inner Race	Outer Race	Shaft Diameter Nominal	Housing Bore Nominal	Shaft Diameter Nominal		Housing Bore Nominal		Bearing Diametral clearance* before installation
010	-0.0004	-0.0005	0.0003	0.0004	0.0004	0.0005	-0.0004	-0.0008	-0.0005	-0.001	0.001	0.0015
015	-0.0005	-0.0005	0.0004	0.0004	0.0005	0.0005	-0.0005	-0.001	-0.0005	-0.001	0.0012	0.0017
017	-0.0006	-0.0005	0.0005	0.0005	0.0006	0.0005	-0.0006	-0.0012	-0.0005	-0.001	0.0012	0.0022
020	-0.0006	-0.0005	0.0005	0.0005	0.0006	0.0005	-0.0006	-0.0012	-0.0005	-0.001	0.0012	0.0022
025	-0.0006	-0.0005	0.0005	0.0005	0.0006	0.0005	-0.0006	-0.0012	-0.0005	-0.001	0.0012	0.0022
030	-0.0006	-0.0006	0.0006	0.0006	0.0006	0.0006	-0.0006	-0.0012	-0.0006	-0.0012	0.0012	0.0022
035	-0.0008	-0.0006	0.0006	0.0006	0.0008	0.0006	-0.0008	-0.0016	-0.0006	-0.0012	0.0016	0.0026
040	-0.0008	-0.0006	0.0006	0.0006	0.0008	0.0006	-0.0008	-0.0016	-0.0006	-0.0012	0.0016	0.0026
042	-0.0008	-0.0008	0.0008	0.0008	0.0008	0.0008	-0.0008	-0.0016	-0.0008	.-00016	0.0016	0.0026
045	-0.0008	-0.0008	0.0008	0.0008	0.0008	0.0008	-0.0008	-0.0016	-0.0008	-0.0016	0.0016	0.0026
047	-0.001	-0.0008	0.0008	0.0008	0.001	0.0008	-0.001	-0.002	-0.0008	-0.0016	0.002	0.003
050	-0.001	-0.0008	0.0008	0.0008	0.001	0.0008	-0.001	-0.002	-0.0008	-0.0016	0.002	0.003
055	-0.001	-0.001	0.001	0.001	0.001	0.001	-0.001	-0.002	-0.001	-0.002	0.002	0.003
060	-0.001	-0.001	0.001	0.001	0.001	0.001	-0.001	-0.002	-0.001	-0.002	0.002	0.003
065	-0.001	-0.001	0.001	0.001	0.001	0.001	-0.001	-0.002	-0.001	-0.002	0.002	0.003
070	-0.001	-0.0012	0.001	0.001	0.001	0.0012	-0.001	-0.002	-0.0012	-0.0024	0.0024	0.0034
075	-0.0012	-0.0012	0.0012	0.0012	0.0012	0.0012	-0.0012	-0.0024	-0.0012	-0.0024	0.0024	0.0034
080	-0.0012	-0.0012	0.0012	0.0012	0.0012	0.0012	-0.0012	-0.0024	-0.0012	-0.0024	0.0024	0.0034
090	-0.0012	-0.0012	0.0012	0.0012	0.0012	0.0012	-0.0012	-0.0024	-0.0012	-0.0024	0.0024	0.0034
100	-0.0014	-0.0014	0.0014	0.0014	0.0014	0.0014	-0.0014	-0.0028	-0.0014	-0.0028	0.0028	0.0038
110	-0.0014	-0.0014	0.0014	0.0014	0.0014	0.0014	-0.0014	-0.0028	-0.0014	-0.0028	0.0028	0.0038
120	-0.0014	-0.0014	0.0014	0.0014	0.0014	0.0014	-0.0014	-0.0028	-0.0014	-0.0028	0.0028	0.0038
140	-0.0014	-0.0014	0.0014	0.0014	0.0014	0.0014	-0.0014	-0.0028	-0.0014	-0.0028	0.0028	0.0038
160	-0.0016	-0.0016	0.0016	0.0016	0.0016	0.0016	-0.0016	-0.0032	-0.0016	-0.0032	0.0032	0.0042
180	-0.0016	-0.0016	0.0016	0.0016	0.0016	0.0016	-0.0016	-0.0032	-0.0016	-0.0032	0.0032	0.0042
200	-0.0018	-0.0018	0.0018	0.0018	0.0018	0.0018	-0.0018	-0.0036	-18	-0.0036	0.0036	0.0046
210	-0.0018	-0.0018	0.0018	0.0018	0.0018	0.0018	-0.0018	-0.0036	-18	-0.0036	0.0036	0.0046
220	-0.0018	-0.0018	0.0018	0.0018	0.0018	0.0018	-0.0018	-0.0036	-18	-0.0036	0.0036	0.0046
250	-0.0018	-0.0018	0.0018	0.0018	0.0018	0.0018	-0.0018	-0.0036	-0.0018	-0.0036	0.0036	0.0046
300	-0.0018	-0.0018	0.0018	0.0018	0.0018	0.0018	-0.0018	-0.0036	-0.0018	-0.0036	0.0036	0.0046
350	-0.002	-0.002	0.002	0.002	0.002	0.002	-0.002	-0.004	-0.002	-0.004	0.004	0.005
400	-0.002	-0.002	0.002	0.002	0.002	0.002	-0.002	-0.004	-0.002	-0.004	0.004	0.005

* Diametral clearance after installation theoretically can range rather widely if all contributing bearing, housing, and shaft tolerances are at either of their extremes. Diametral clearances shown do not apply to Type A (angular contact) bearings.

KAYDON type C, X and A thin section bearing, Precision class 3 (Ref. ABEC 3F)

Bearing size (inch series)	Bearing diameters		Radial & Axial runout		Rotating Shaftor Duplex DF Mounting		Stationary Shaftor Duplex DB Mounting				Bearing Diametral clearance* (Type “X” and “C” only) before installation
Bearing size (inch series)	Bearing Bore Nominal	Bearing O.D. Nominal	Inner Race	Outer Race	Shaft Diameter Nominal	Housing Bore Nominal	Shaft Diameter Nominal		Housing Bore Nominal
010	–.0002	–.0003	0.0003	0.0004	0.0002	0.0003	–.0002	–.0004	–.0003	–.0006	0.0007	0.0011
015	–.0003	–.0003	0.0004	0.0004	0.0003	0.0003	–.0003	–.0006	–.0003	–.0006	0.0008	0.0012
017	–.0004	–.0004	0.0004	0.0005	0.0004	0.0004	–.0004	–.0008	–.0004	–.0008	0.0008	0.0018
020	–.0004	–.0004	0.0004	0.0005	0.0004	0.0004	–.0004	–.0008	–.0004	–.0008	0.0008	0.0018
025	–.0004	–.0004	0.0004	0.0005	0.0004	0.0004	–.0004	–.0008	–.0004	–.0008	0.0008	0.0018
030	–.0004	–.0004	0.0004	0.0006	0.0004	0.0004	–.0004	–.0008	–.0004	–.0008	0.0008	0.0018
035	–.0005	–.0004	0.0005	0.0006	0.0005	0.0004	–.0005	–.0010	–.0004	–.0008	0.001	0.002
040	–.0005	–.0004	0.0005	0.0006	0.0005	0.0004	–.0005	–.0010	–.0004	–.0008	0.001	0.002
042	–.0005	–.0005	0.0005	0.0008	0.0005	0.0005	–.0005	–.0010	–.0005	.–0010	0.001	0.002
045	–.0005	–.0005	0.0005	0.0008	0.0005	0.0005	–.0005	–.0010	–.0005	–.0010	0.001	0.002
047	–.0006	–.0005	0.0006	0.0008	0.0006	0.0005	–.0006	–.0012	–.0005	–.0010	0.0012	0.0022
050	–.0006	–.0005	0.0006	0.0008	0.0006	0.0005	–.0006	–.0012	–.0005	–.0010	0.0012	0.0022
055	–.0006	–.0006	0.0006	0.0009	0.0006	0.0006	–.0006	–.0012	–.0006	–.0012	0.0012	0.0022
060	–.0006	–.0006	0.0006	0.0009	0.0006	0.0006	–.0006	–.0012	–.0006	–.0012	0.0012	0.0022
065	–.0006	–.0006	0.0006	0.0009	0.0006	0.0006	–.0006	–.0012	–.0006	–.0012	0.0012	0.0022
070	–.0006	–.0007	0.0006	0.001	0.0006	0.0007	–.0006	–.0012	–.0007	–.0014	0.0014	0.0024
075	–.0007	–.0007	0.0008	0.001	0.0007	0.0007	–.0007	–.0014	–.0007	–.0014	0.0014	0.0024
080	–.0007	–.0007	0.0008	0.001	0.0007	0.0007	–.0007	–.0014	–.0007	–.0014	0.0014	0.0024
090	–.0007	–.0007	0.0008	0.001	0.0007	0.0007	–.0007	–.0014	–.0007	–.0014	0.0014	0.0024
100	–.0008	–.0008	0.001	0.0012	0.0008	0.0008	–.0008	–.0016	–.0008	–.0016	0.0016	0.0026
110	–.0008	–.0008	0.001	0.0012	0.0008	0.0008	–.0008	–.0016	–.0008	–.0016	0.0016	0.0026
120	–.0008	–.0009	0.001	0.0014	0.0008	0.0009	–.0008	–.0016	–.0009	–.0018	0.0018	0.0028
140	–.0008	–.0009	0.0012	0.0014	0.0008	0.0009	–.0008	–.0016	–.0009	–.0018	0.0018	0.0028
160	–.0009	–.0010	0.0014	0.0016	0.0009	0.001	–.0009	–.0018	–.0010	–.0020	0.002	0.003
180	–.0009	–.0010	0.0014	0.0016	0.0009	0.001	–.0009	–.0018	–.0010	–.0020	0.002	0.003
200	–.0010	–.0012	0.0016	0.0018	0.001	0.0012	–.0010	–.0020	–.0012	–.0024	0.0024	0.0034

KAYDON type C, X and A thin section bearing, Precision class 4 (Ref. ABEC 4F)

Bearing size (inch series)	Bearing diameters		Radial & Axial Runout				Rotating Shaft or Duplex DF Mounting		Stationary Shaft or Duplex DB Mounting				Bearing Diametral Clearance* (Type “X”and “C” only) Before Installation
	Bearing Bore Nominal	Bearing O.D. Nominal	Inner Race		Outer Race		Shaft Diameter Nominal	Housing Bore Nominal	Shaft Diameter Nominal		Housing Bore Nominal
	Bearing Bore Nominal	Bearing O.D. Nominal	Radial	Axial	Radial	Axial	Shaft Diameter Nominal	Housing Bore Nominal	Shaft Diameter Nominal		Housing Bore Nominal
010	-0.0002	-0.0002	0.0002	0.0003	0.0002	0.0003	0.0002	0.0002	-0.0002	-0.0004	-0.0002	-0.0004	0.0005	0.0009
015	-0.0002	-0.0002	0.0002	0.0003	0.0002	0.0003	0.0002	0.0002	-0.0002	-0.0004	-0.0002	-0.0004	0.0005	0.0009
017	-0.0003	-0.0003	0.0002	0.0003	0.0003	0.0004	0.0003	0.0003	-0.0003	-0.0006	-0.0003	-0.0006	0.0006	0.0012
020	-0.0003	-0.0003	0.0002	0.0003	0.0003	0.0004	0.0003	0.0003	-0.0003	-0.0006	-0.0003	-0.0006	0.0006	0.0012
025	-0.0003	-0.0003	0.0002	0.0003	0.0003	0.0004	0.0003	0.0003	-0.0003	-0.0006	-0.0003	-0.0006	0.0006	0.0012
030	-0.0003	-0.0003	0.0002	0.0003	0.0004	0.0005	0.0003	0.0003	-0.0003	-0.0006	-0.0003	-0.0006	0.0006	0.0012
035	-0.0003	-0.0003	0.0003	0.0004	0.0004	0.0005	0.0003	0.0003	-0.0003	-0.0006	-0.0003	-0.0006	0.0006	0.0012
040	-0.0003	-0.0003	0.0003	0.0004	0.0004	0.0005	0.0003	0.0003	-0.0003	-0.0006	-0.0003	-0.0006	0.0006	0.0012
042	-0.0003	-0.0004	0.0003	0.0004	0.0004	0.0005	0.0003	0.0004	-0.0003	-0.0006	-0.0004	-0.0008	0.0008	0.0014
045	-0.0003	-0.0004	0.0003	0.0004	0.0004	0.0005	0.0003	0.0004	-0.0003	-0.0006	-0.0004	-0.0008	0.0008	0.0014
047	-0.0004	-0.0004	0.0003	0.0004	0.0004	0.0005	0.0004	0.0004	-0.0004	-0.0008	-0.0004	-0.0008	0.0008	0.0014
050	-0.0004	-0.0004	0.0003	0.0004	0.0004	0.0005	0.0004	0.0004	-0.0004	-0.0008	-0.0004	-0.0008	0.0008	0.0014
055	-0.0004	-0.0005	0.0003	0.0004	0.0005	0.0006	0.0004	0.0005	-0.0004	-0.0008	-0.0005	-0.001	0.001	0.0016
060	-0.0004	-0.0005	0.0003	0.0004	0.0005	0.0006	0.0004	0.0005	-0.0004	-0.0008	-0.0005	-0.001	0.001	0.0016
065	-0.0004	-0.0005	0.0003	0.0004	0.0005	0.0006	0.0004	0.0005	-0.0004	-0.0008	-0.0005	-0.001	0.001	0.0016
070	-0.0004	-0.0005	0.0003	0.0004	0.0005	0.0006	0.0004	0.0005	-0.0004	-0.0008	-0.0005	-0.001	0.001	0.0016
075	-0.0005	-0.0005	0.0004	0.0005	0.0005	0.0006	0.0005	0.0005	-0.0005	-0.001	-0.0005	-0.001	0.001	0.0016
080	-0.0005	-0.0005	0.0004	0.0005	0.0005	0.0006	0.0005	0.0005	-0.0005	-0.001	-0.0005	-0.001	0.001	0.0016
090	-0.0005	-0.0005	0.0004	0.0005	0.0005	0.0006	0.0005	0.0005	-0.0005	-0.001	-0.0005	-0.001	0.001	0.0016
100	-0.0005	-0.0005	0.0005	0.0006	0.0006	0.0007	0.0005	0.0005	-0.0005	-0.001	-0.0005	-0.001	0.001	0.0016
110	-0.0005	-0.0005	0.0005	0.0006	0.0006	0.0007	0.0005	0.0005	-0.0005	-0.001	-0.0005	-0.001	0.001	0.0016
120	-0.0005	-0.0006	0.0005	0.0006	0.0007	0.0008	0.0005	0.0006	-0.0005	-0.001	-0.0006	-0.0012	0.0012	0.0018
140	-0.0006	-0.0006	0.0005	0.0007	0.0007	0.0008	0.0006	0.0006	-0.0006	-0.0012	-0.0006	-0.0012	0.0012	0.0018
160	-0.0006	-0.0007	0.0007	0.0008	0.0008	0.0009	0.0006	0.0007	-0.0006	-0.0012	-0.0007	-0.0014	0.0014	0.002
180	-0.0006	-0.0007	0.0007	0.0008	0.0008	0.0009	0.0006	0.0007	-0.0006	-0.0012	-0.0007	-0.0014	0.0014	0.002
200	-0.0007	-0.0008	0.0008	0.0009	0.0009	0.001	0.0007	0.0008	-0.0006	-0.0014	-0.0007	-0.0016	0.0016	0.0022

KAYDON type C, X and A thin section bearing, Precision class 6 (Ref. ABEC 7F)

Bearing size (inch series)	Bearing diameters		Radial & Axial runout		Rotating Shaftor Duplex DF Mounting		Stationary Shaftor Duplex DB Mounting				Bearing Diametral clearance* (Type “X” and “C” only) before installation
Bearing size (inch series)	Bearing Bore Nominal	Bearing O.D. Nominal	Inner Race	Outer Race	Shaft Diameter Nominal	Housing Bore Nominal	Shaft Diameter Nominal		Housing Bore Nominal
10	–.00015	–.0002	0.00015	0.0002	0.00015	0.0002	–.00015	–.0003	–.0002	–.0004	0.0004	0.0008
15	–.0002	–.0002	0.00015	0.0002	0.0002	0.0002	–.0002	–.0004	–.0002	–.0004	0.0004	0.0008
17	–.0002	–.0002	0.00015	0.0002	0.0002	0.0002	–.0002	–.0004	–.0002	–.0004	0.0004	0.001
20	–.0002	–.0002	0.00015	0.0002	0.0002	0.0002	–.0002	–.0004	–.0002	–.0004	0.0004	0.001
25	–.0002	–.0002	0.00015	0.0002	0.0002	0.0002	–.0002	–.0004	–.0002	–.0004	0.0004	0.001
30	–.0002	–.0003	0.00015	0.0002	0.0002	0.0003	–.0002	–.0004	–.0003	–.0006	0.0006	0.0012
35	–.00025	–.0003	0.0002	0.0002	0.00025	0.0003	–.00025	–.0005	–.0003	–.0006	0.0006	0.0012
40	–.00025	–.0003	0.0002	0.0002	0.00025	0.0003	–.00025	–.0005	–.0003	–.0006	0.0006	0.0012
42	–.00025	–.0004	0.0002	0.0003	0.00025	0.0004	–.00025	–.0005	–.0004	–.0008	0.0008	0.0014
45	–.00025	–.0004	0.0002	0.0003	0.00025	0.0004	–.00025	–.0005	–.0004	–.0008	0.0008	0.0014
47	–.0003	–.0004	0.0003	0.0003	0.0003	0.0004	–.0003	–.0006	–.0004	–.0008	0.0008	0.0014
50	–.0003	–.0004	0.0003	0.0003	0.0003	0.0004	–.0003	–.0006	–.0004	–.0008	0.0008	0.0014
55	–.0003	–.0004	0.0003	0.0003	0.0003	0.0004	–.0003	–.0006	–.0004	–.0008	0.0008	0.0014
60	–.0003	–.0004	0.0003	0.0003	0.0003	0.0004	–.0003	–.0006	–.0004	–.0008	0.0008	0.0014
65	–.0003	–.0004	0.0003	0.0003	0.0003	0.0004	–.0003	–.0006	–.0004	–.0008	0.0008	0.0014
70	–.0003	–.0004	0.0003	0.0004	0.0003	0.0004	–.0003	–.0006	–.0004	–.0008	0.0008	0.0014
75	–.0004	–.0004	0.0003	0.0004	0.0004	0.0004	–.0004	–.0008	–.0004	–.0008	0.0008	0.0014
80	–.0004	–.0004	0.0003	0.0004	0.0004	0.0004	–.0004	–.0008	–.0004	–.0008	0.0008	0.0014
90	–.0004	–.0004	0.0003	0.0004	0.0004	0.0004	–.0004	–.0008	–.0004	–.0008	0.0008	0.0014
100	–.0005	–.0005	0.0004	0.0004	0.0005	0.0005	–.0005	–.0010	–.0005	–.0010	0.001	0.0016
110	–.0005	–.0005	0.0004	0.0004	0.0005	0.0005	–.0005	–.0010	–.0005	–.0010	0.001	0.0016
120	–.0005	–.0005	0.0004	0.0005	0.0005	0.0005	–.0005	–.0010	–.0005	–.0010	0.001	0.0016
140	–.0005	–.0006	0.0004	0.0005	0.0005	0.0006	–.0005	–.0010	–.0006	–.0012	0.0012	0.0018

Reali-Slim sealed thin section bearings

In order to take full advantage of anti-friction bearings, it is important to keep them clean and well lubricated. Properly designed and installed seals and guards help achieve this.

Seal: A contact closure between a stationary and rotating part that retains lubricant within the bearing and prevents foreign matter from entering the bearing. The seal is fixed in the outer ring and in close contact with the inner ring.

Shield: A closure device that serves the same purpose as a seal, but without the positive contact.

The seal is effective, but requires turning force (torque), generates heat, and therefore has a lower speed limit than open or shielded Reali-Slim bearings. Reali-Slim bearings can be integrally sealed or externally sealed. Lubricant and lubrication system, torque requirements, speed and operating environment will influence selection. Integral seals and guards provide a very compact overall design and have the added advantage of protecting the bearings before, during and after installation. EA/EB bearings are used where a guard is sufficient or where a guard is required due to torque or speed limitations. When weight and space are at a premium and a seal or guard is required on only one side, single-seal or single-shield bearings are available as custom options. NOTE: Sealed Reali-Slim bearings are pre-lubricated with general purpose grease. Operating conditions (i.e. time, temperature, speed, environment) may cause premature degradation of lubrication. A variety of lubricants are available to meet your specifications.

Lubrication and maintenance

Lubricants in anti-friction bearings reduce friction and wear between moving parts, dissipate heat and prevent corrosion on critical surfaces. Kaydon recommends selecting the appropriate lubricant based on the system design engineer’s evaluation of operating conditions, including at a minimum: rotational speed, load type and size, and ambient temperature. The three commonly used lubricants are oil, grease and dry film or surface treatment.

Oil generally provides complete lubrication. Due to its liquid state, it provides better coverage of key surfaces and helps dissipate heat easily, the latter especially when providing circulation and cooling. Oil is necessary in high-speed applications where the heating effect is pronounced. Oil usually provides lower friction values when minimum torque is required.

Because grease is easily retained, the design of the bearing housing and seals is simplified. In many applications, the lubricant itself can act to exclude contaminants when used in conjunction with labyrinths or tight gaps between rotating and stationary structures. For higher speeds in the range suitable for grease lubrication, channel-type greases are usually chosen.

Dry film and surface treatments have been used as bearing lubricants in applications in extreme environments, especially where conventional lubricants cannot withstand or survive. Several types are available; options include tungsten disulfide, graphite, and molybdenum disulfide.

It is important to note that the amount of lubricant affects bearing performance under specific operating conditions. If a film of oil is maintained on all contact surfaces, only relatively small amounts of lubricant are needed to reduce friction and wear. At higher speeds, excess oil or grease can lead to higher operating temperatures, which can lead to early bearing fatigue. Typical grease fill levels range from 10% to 30% of the bearing’s available free space, depending on the bearing design and application.

Sealed bearings are equipped with an anti-corrosion oil coating to prevent corrosion during storage. Kaydon recommends using clean petroleum solvent to remove preservatives before lubrication. If the anti-corrosion oil is not removed, the compatibility of the lubricant with the anti-corrosion oil must be confirmed.

To realize the full potential of Reali-Slim bearings, Kaydon recommends that customers’ maintenance instructions and plans should take into account operating conditions and include procedures to ensure that the bearings are adequately protected against intrusion of all types of foreign matter, and that fresh oil or grease is introduced with sufficient frequency to Clean bearings and ensure adequate lubrication.