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Plastic Bearing Inserts


Plastic bearing inserts are designed to replace self-aligning ball or roller bearings with a spherical O.D. within the housing. Our precision plastic bearing inserts are available in UHMW and a high-temp acetal material capable of handling temperatures up to 600°F; we can also supply specific materials and specific sizes that are not listed in the charts below. Our stock sizes range from 1/2" up to 3" inside diameter. Being directly interchangeable with a broad spectrum of brands mean that these bearing inserts do not require a new or special housing. Plastic bearings are becoming more popular in many industries such as food and beverage, water treatment, FDA monitored applications, and many more! With superior wear, abrasion, and anti-corrosive characteristics, our plastic bearing inserts have become the top choice for many end-users, resellers, and OEMs alike. Contact our customer support team for pricing and availability.

High Temp Plastic Insert Bearings

Our standard UHMW plastic bearing inserts can handle temperatures up to 200°F; this is the standard for most industrial bearings. In standard circumstances, over 200°F and up to 500°F applications specific seals, greases, fittings, and housings are required. However, with our HT plastic bearing inserts, these additional costs and maintenance can be eliminated. Our high-temp bearings require no lubrication and can operate in applications exposed to temperatures up to 600°F and retrofit into standard housings. Precision machined from pure virgin high-temp material; these bearings produce a simple solution to a long-standing industry problem.

Plastic Insert Bearing Sizes


Part #
Bore Size
Diameter (A)
Width (B)
Part #
Bore Size
Diameter (A)
Width (B)
PI-12 1/2" 1.575" 1.024" PI-1-716 1-7/16" 2.835" 1.496"
PI-916 9/16" 1.575" 1.024" PI-1-12 1-1/2" 3.150" 1.732"
PI-58 5/8" 1.575" 1.024" PI-1-916 1-9/16" 3.150" 1.732"
PI-1116 11/16" 1.575" 1.024" PI-1-58 1-5/8" 3.346" 1.732"
PI-34 3/4" 1.850" 1.182" PI-1-1116 1-11/16" 3.346" 1.732"
PI-1316 13/16" 2.047" 1.182" PI-1-34 1-3/4" 3.346" 1.732"
PI-78 7/8" 2.047" 1.182" PI-1-78 1-7/8" 3.543" 1.732"
PI-1516 15/16" 2.047" 1.182" PI-1-1516 1-15/16" 3.543" 1.732"
PI-1 1" 2.047" 1.182" PI-2 2" 3.543" 1.732"
PI-1-16 1-1/16" 2.441" 1.418" PI-2-18 2-1/8" 3.937" 1.968"
PI-1-18 1-1/8" 2.441" 1.418" PI-2-316 2-3/16" 3.937" 1.968"
PI-1-316 1-3/16" 2.441" 1.418" PI-2-14 2-1/4" 4.331" 2.126"
PI-1-14 1-1/4" 2.835" 1.496" PI-2-38 2-3/8" 4.331" 2.126"
PI-1-516 1-5/16" 2.835" 1.496" PI-2-716 2-7/16" 4.331" 2.126"
PI-1-38 1-3/8" 2.835" 1.496" -- -- -- --

Plastic Bearing Insert Interchange Chart

The chart below shows the interchange data for our plastic insert bearings for the most common bearing manufacturers; this means the housing and associated components will not need to be replaced for additional interchange data on brands not listed below contact, our product specialists division for assistance.
Manufacturer
Series
*Exceptions (Bore Size)
BCA, Federal NPS RR, NPS RP, WPS GP, WPS GR, B -
Browning B100, B150,B200X, B220X, B250X -
Dodge SC, SL 1/2" - 11/16", 1-5/8", 2", 2-1/4"
Eagle Pitcher HC200, SA200, SB200, UC200 1/2" - 5/8"
Fafnir MUB, G KPPB, KLLB, KRRB, G KLLB, G KRRB, GRA PPB, GRA RRB, RA PPB, RA RRB -
Hoover-NSK RA BTT, RAG BTT, SGB, SB BFF, SBG BFF -
Lin-Belt (FMC) Y N, Y NL, U HL, W UL, WG UL 2"
McGill KMB25 1-3/16", 1-5/8", 2", 2-1/4"
Morse-Sealmaster 2, L, 2D, 2L 1/2" - 11/16"
SKF YAR, YET, YEL -

Plastic Bearing Insert Speed and Load Data

Determination of the bearing loads, drive factor, and PV value is imperative for new application bearing sizing and selection. The placement of a drive system concerning the bearing supporting it can significantly impact the lives of those bearings; the more even that a load is dispersed over a bearing set, the longer the bearings will last. Formulas for determining bearing loads are shown below.

Equations for Determining Bearing Loads:
L = Total shaft load on bearings (pounds)
N = Revolusions per minue
r = Radius at which load acts (inches)
T = Torque (inch-pounds or foot-pounds) (see below)
f = 'f' factor from Driven Factor Table (table below)

Drive Factor Table ('f')
Type of Drive
'f' Factor
Chain 1.0
Flat Belt - 180° Wrap 2.5
Flat Belt - Less Than 180 ° Wrap 3.0
V-Belt 2.0
Wire Rope - 45° Grooved Pulley 2.0
Wire Rope - 60° Grooved Pulley 3.0
After the approximate load has been determined (from known data or by using the above formulas), the PV value can be calculated.
Equations for Determining PV Value:
P = Bearing Load (psi)
A = Bearing Area (square inches)
L = Load on Bearing (pounds)
V = Velocity of The Shaft (surface feet/ minute = SFM)
RPM = Revolutions Per Minute of Shaft
D = Shaft Diameter (inches)
I = Length of Bushing Through The Bore (inches)

PV Value:
The operating PV of a bearing is actually a measurement of temperature. The maximum allowable PV for any situation will vary depending on the thermal and mechanical characteristics of the material selected for the bearing. Because of this, the ambient air temperature of the environment and the corresponding housing temperature is important. Since heat is a major factor in determining the life of a bearing, the ability to dissipate heat through the shaft with a lubricant or by operation in a spray or bath will reduce the bearing failure rate or increase bearing life. Another factor in reducing the life of any bearing is chemical action on a material not suited for such an environment. Any abrasives introduced to a bearing will wear away the bearing material and significantly reduce its life. Most plastic materials will absorb some abrasive particles to a much greater degree than a metal bearing and therefore reduce the damage done to both the shaft and the bearing. Still, it will not totally eliminate that wear.

Plastic Insert Bearing Speed and Load Rating Chart

The data on the below charts is about our UHMW self-aligning inserts in unlubricated conditions. Since the high-end range for operation temperatures on the standard bearings is 180°F to 200°F. Since this material has a low coefficient of friction and thermal conductivity, PV values must be carefully calculated.
The below chart shows information that is calculated as not to exceed the following limits for UHMW insert bearing applications:
  • Maximum Pressure (P) = 800 lbs/in
  • Maximum Velocity (V) = 50 surface feet/ minute
Note: for UHMW, the combination of PV may not exceed 3000; for PVs that exceed 3000, consult our customer support team for material options.
If ambient temperatures are low or the bearing is to be continually operated in water or other liquids and is sufficiently cooled, the PV limits may be increased as long as the bearing temperature is not exceeded. Lubrication can also increase the operating PV limits by providing a lower coefficient of friction on the bearing. It's important to note that our self-aligning plastic bearing inserts are designed to replace self-aligning ball and roller bearing inserts within the same conventional housing. Because our bearings are self-aligning to the same degree as their steel counterparts, no changes are necessary to utilise these bearings within the equipment or bearing housing.
Bearing Bore Size
Max Speed (RPM)
Max Radial Load (LBS)
1/2" 350 200
9/16" 300 216
5/8" 275 233
11/16" 250 266
3/4" 225 333
13/16" 200 366
7/8" 200 400
15/16" 175 433
1" 175 466
1-1/16" 150 600
1-1/8" 150 633
1-3/16" 150 665
1-1/4" 125 733
1-5/16" 125 766
1-3/8" 125 800
1-7/16" 125 833
1-1/2" 100 1033
1-9/16" 100 1066
1-5/8" 100 1100
1-11/16" 100 1166
1-3/4" 100 1200
1-7/8" 75 1266
1-15/16" 75 1333
2" 75 1566
2-1/8" 75 1666
2-3/16" 75 1700
2-1/4" 75 1900
2-3/8" 50 200
2-7/16" 50 2066

UHMW Bearing Material Data

The term UHMW its self stands for ultra-high molecular material. UHMW material possesses a unique combination of physical and mechanical properties that enable it to perform well under the most rigorous conditions of wear and environment. It has the highest known impact strength of any thermoplastic that is currently manufactured, plus very high resistance to abrasion against a wide variety of material. These properties make this material an exceptional option for industrial impact, wear surfaces, and sliding operations. UHMW is also FDA and USDA approved for direct contact in food processing applications. For Polyethylene to be certified as UHMW the molecular weight of the material must be at least 4 million (4 PPM). Our UHMW material is certified at 4-6 million molecular weight and any material with less than 4 million molecular weight is either high density to low density (HD or LD) polyethylene. These products are much less expensive to manufacture than UHMW, but the physical properties are correspondingly less. At USA Roller Chain we certify that only polyurethane grater than 4.2 million molecular weight is used in our plastic insert bearings for the best performance and wear life.
The below chart goes through the specific mechanical properties of our UHMW plastic bearing inserts
Property ASTM Test Units Metric (US) Typical Values
Specific Gravity D792 gm/cm° 0.926-0.934
Tensile Strength @ Yield D638 MPa (PSI) 21 (3100)
Tensile Strength @ Break D638 MPa (PSI) 48 (7000)
Elongation @ Break D638 % 350
Young's ("E") Modulus (23°C) D638 MPa (PSI 10 5) 690 (1.0)
Young's ("E") Modulus (-269°C) D638 MPa (PSI 10 5) 2970 (4.3)
Izod Impact Strength (23°C) D256(1) J/m (ft-LBS/in notch) 140 (30)
Izod Impact Strength (-40°C) D256(1) J/m (ft-LBS/in notch) 100 (21)
Hardness, Shore "D" D2240 - 62-66
Abrasion Resistance (2) - 100
Water Absorption D570 % Nil
Relative Solution Viscosity D4020 dl/gm 2.3-3.5
Density - (lbs./cubic in.) .034
1. Izod Impact Strength: Samples have two (15° +/- 1/2°) notches on the opposite sides to a depth of 5mm.
2. See description of test method - under sand-slurry test results.
Property ASTM Test Units Metric (US) Typical Values
Temperature Range - °F -269° to 160°
Crystalline Melting Range, Powder Polarizing Microscope °C (°F) 138-142 (280-289)
Coefficient of Linear Expansion: 20 to 100°C D696 K-1 ~2 10 -4
Coefficient of Linear Expansion: -200 to -100°C D696 K -1 ~0.5 10 -4

Property ASTM Test Units Metric (US) Typical Values
Volume Resistivity D257 Ohm cm > 5 1016
Dielectric Strength D149 KV/cm (V/mil) 900 (2300)
Dielectric Constant (Er) D150 - 2.30
Dissipation Factor (tan ð) at: 50 Hz D150 - 1.9 10 -4
Dissipation Factor (tan ð) at: 103 Hz D150 - 0.5 10-4
Dissipation Factor (tan ð) at: 105 Hz D150 - 2.5 10 -4
Property UHMW Nylon 6 Nylon 6/6 Nylon/MoS2 PTFE Acetal Copolymet
Dry .10-.22 .15-.40 .15-.40 .12-.20 .04-.25 .15-.35
Water .05-.10 .14-.19 .14-.19 .10-.12 .04-.08 .10-.20
Oilq.05-.08 .02-.11 .02-.11 .08-.10 .5-.05 .05-.10 -

Test Specimens: Dumb-bell type; Duration of Test: 30 days
A. Resistant: Mechanical properties not appreciably affected
B. Limited Resistance: Decrease in yield stress and ultimate tensile strength less than 20%
C. Not Resistant: Decrease in yield stress and an ultimate tensile strength greater than 20%
I. Inorganic Acids
Reagent 20°C 50°C 80°C
Chromic Acid (80%) A A B
Hydrochloric Acid (conc.) A A A
Hydrocyanic Acid A A -
Hydrofluoric Acid A A -
Nitric Acid (conc.) C C C
Nitric Acid (50%) B C C
Nitric Acid (20%) A A B
Phosphoric Acid (85%) A A A
Sulfuric Acid (conc.) A C C
Sulfuric Acid (75%) A B B
II. Alkalis
Reagent 20°C 50°C 80°C
Aqueous Ammonia A A -
Potassium Hydroxide Solution A A A
Sodium Hydroxide Solution A A A
III. IAqueous Solutions of Inorganic Salts
Reagent 20°C 50°C 80°C
Aluminum Chloride A A A
Ammonium Nitrate A A A
Bleaching Powder A A A
Calcium Chloride A A A
Sodium Carbonate A A A
Sodium Chloride A A A
Nitric Acid (20%) A A A
Sodium Hypochlorite A A A
Zinc Chloride A A A
IV. Organic Acids
Reagent 20°C 50°C 80°C
Acetic Acid (99%) A A B
Acetic Acid (10%) A A A
Butyric Acid A A -
Citric Acid A A A
Formic Acid A A -
Oleic Acid A A B
V. Hydrocarbons & Halogenated Hydrocarbons
Reagent 20°C 50°C 80°C
Benzene B B -
Carbon Tetrachloride B - -
Cyclohexane A A -
Dichloroethylene C C -
Diesel Oil A A B
n-Heptane A - -
Petroleum Ether A - -
Trichloroethylene B C -
Toluene B C -
White Spirit A B -
Xylene B B C
VI. Alcohol, Ketones, Ester and Amines
Reagent 20°C 50°C 80°C
Acetone A A -
Aniline A A B
Benzyl Alcohol A A A
Butyl Alcohol A A -
Cyclohexanol A A A
Ethanol A A -
Ethyl Acetate A A -
Ethylene Glycol A A A
Glycerin A A A
Lauryl Alcohol A A A
Propyl Alcohol A A A
VII. Miscellaneous
Reagent 20°C 50°C 80°C
Beer / Wine A A A
Detergents in Aqueous Solution A A A
Distilled Water A A A
Hydrogen Peroxide 30% (Perhydrol) A A -
Linseed Oil / Olive Oil A A A
Milk A A A
Sea Water A A A
*The information above and contained herein is, to our best knowledge, true and accurate, but all of the recommendations and suggestions are made without guarantee since the conditions of use are beyond our control. We disclaim any liability incurred in connection with the use of these data or suggestions. This publication is not to be taken as a license to operate under, or a recommendation to infringe any patents. The observance of all legal regulations and patents is the responsibility of the user.
The abrasion resistance of UHMW is illustrated in the sand-slurry diagram below. These tests were conducted for a period of 7.5 hours at a speed of 1750 RPM. Results for convention wear-resistant materials are expressed as a percentage based on the volume of material lost. A carbon steel standard was assigned a value of 100. The lower values represent an increased resistance to abrasion.
Sand-Slurry Test Results
IV. Organic Acids
UHMW 44 Medium Density Polyethylene 125
AR Steel 52 Phosphor Bronze 190
Polybutylene 56 Polypropylene 190
TFE 72 Phenolic Laminate L.E. 200
304 Stainless Steel 84 Polysulfone 300
Polycarbonate 96 Yellow Brass 400
Carbon Steel 100 Low Density Polyethylene 530
High Density Polyethylene 109 Maple Wood 690
Polyacetal 110 Hard Neoprene 800




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