Wheel Selection Tips




WHEEL BEARINGS

Precision Tapered Roller Bearings. Ideal for heavy duty and power-towed caster applications because their tapered faces will handle any combination of downward and side forces. Used in various Hamilton swivel assemblies as well as in wheels.

Two bearings are installed per wheel, one in each side of the hub, consisting of a cup (hardened and ground outer raceway) and cone (roller assembly). Spanner bushings are not employed since adjustment requires tightening caster legs against the bearing assembly. Tapered bearings extend overall hub length of the wheel itself by approximately 1/4". (Shown above with optional integral seal.)

Precision Ball Bearings. Best suited when rollability is important and side thrust is not a critical factor.  (Tapered bearings are best suited where side thrust is critical.) The bearings are pre-lubricated and sealed at the factory so greasing is not required, reducing maintenance costs.....  Double-sealed precision ball bearings (shown on left) incorporate steel reinforced rubber seals securely fastened to a groove on the ring of both sides of the bearings. They now replace straight roller bearings in the majority of our casters using polyurethane tread and solid urethane wheels and can be provided optionally on many other wheel types.  Shielded stainless steel precision ball bearings (shown on right) are used in our stainless steel and solid urethane wheels to prevent rust and improve rollability.  On special order we can supply additional sizes and configurations including flanged, sealed square bores, extended inner raceways, and wide inner raceways with self-locking collars.

Straight Roller Bearings. Most popular anti-friction bearing for industrial equipment. Consists of a cage-type roller assembly, and an outer race that may be separate or integral.  (Note: plastic retaining washers or other components may be used unless we are advised of a high-heat application.)

Oilless Sleeve Bearings. A sleeve, usually of sintered iron or oil-impregnated bronze, is press-fit into the wheel bore. Lacks the ease of movement anti-friction bearings provide, but practical for light loads or where re-lubrication is a problem. (A light application of oil or graphite improves rollability and extends bearing life.)

Plastic Bearings. For environments detrimental to metal bearings, acetyl resin bearings offer chemical and corrosion resistance. Delrin® (registered DuPont trademark) is a standard offering in certain wheels, as either a sleeve or flange type bearing. Plastic bearings can be custom machined and installed in most other Hamilton Wheels on request. Note: flange type bearings extend actual hub length of wheel approximately 3/16".

Non-Precision Ball Bearings. The standard ball bearings referred to in this catalog are the unground radial type, intended for light-to-medium duty service. On special order we can supply light or heavy-duty precision ball bearings for both radial and thrust loads, ln configurations including flanged, sealed, square bores, extended inner raceways, and wide inner raceways with self-locking collars.

Plain Bore. The term applied to running machine-bored wheels directly on an axle; hence, the absence of a bearing. Suitable for light or seldom moved loads, where ease of starting and rolling is not too important or where price is a dominant factor. Except for roller bearing bores, Hamilton normally machines "plain bore" wheels 1Ú64" oversize for good running fit. Closer tolerance machining available at extra cost.

Special Bearings. For most applications, the bearings discussed above work quite effectively. However, there is an occasional requirement for bearings with special features and characteristics.

For example, alloy bronze bearings and ferrous alloy bearings are designed for high heat applications. Teflon® impregnated bronze bearings eliminate the need for lubrication and operate effectively in hostile environments. Roller clutch bearings permit a wheel to roll in only one direction and square bearings allow wheels to roll on a square shaft. Ask for a Product Engineer to help you with any unusual requirements.




WHEEL CHARACTERISTICS-Comparative Ratings1
Ordering Symbol
Ease of Rolling2
Quiet Operation
Floor Protection3
Cushioing (Resilience)
Impact Resistance
Moisture and Water Resistance
Abration Resistance
Relative Cost
Temperature Range4
Forged Steel
-FS
High
Very High
No
Poor
Low
High
High
Very High
High
-30°-600°
Metal
-M
High
High
No
Poor
Low
Low5
High
High
Low
-30°-600°
Stainless
-S
High
High
No
Poor
Low
Med .
High
High
High
-30°-600°
Plastex
-P
High
High
No
Fair
Low
Med.
Low
Med.
Low
-50°-300°8
Nylast™  -NY  High High  Yes  Good  Low  Med.  High  Med.  High  -30°-200°
Aqualite®
-A
High
Med.
No
Fair
Med.
Med.
High
Med.
Low
-20°-200°8
Unilast ™
-UY
High
Med.
Yes
Good8
Low
Med.
High
Med.
Med.
-50°-180°
Duralast® XC  -D70  High  Med. Yes  Good Med. Med. Med. High  High -50°-200°
Superlast® XC  -SY70  High  High Yes  Good Med. High Med. High  High -50°-200°
Super Ultralast™  -STR  Highest  High Yes Best Highest Med. Med. Med.  Highest -50°-200°
Swivel-EAZ®  -SWF  High  Low Yes Best High  High Med. Med.  High -50°-200°
Ultralast™  -TR  Highest Med.  Yes  Best  Highest  Med.  Med.  Med.  Highest  -50°-200°
Superlast®
-SY
Med.
High
Yes
Good8
High
Very High
Med.
High
High
-50°-200°
Duralast®
-D
Med.
High
Yes
Good8
Med.
Med.
Med.
High
High
-50°-200°
Poly-Soft®
-SP
High
Med
Yes
Very Good
High
High
Med.
High
High
-50°-175°
Polylast
-AY
Med.
Med.
Yes
Good8
Med.
Low
Med.
High
Med.
-50°-180°
Poly-Tech®
-NF
Med.
Med.
Yes
Good
Med.
Med.
High
High
Med.
-30°-180°
Ebonite
-E
High
Med.
No
Fair
Low
Low
High
Med.
Low
0°-130°
HD Semi-Pneumatic  -SPRT  Low High Yes Good Highest Highest Med. Low  Highest  -30°-120°
Flexonite
-F
Low
Low
Yes
Good
High
Med.
High
Low
Low
-40°-120°
Super-Flex ™
-SU
Very Low
Low
Yes
Good
Very High
High
Med.
Low
High
-40°-120°
Moldon Rubber
-R
Low
Low6
Yes
Good
High
High
Med7
Low
Med.
-70°-160°
 Rubber on Aluminum  -RA  Low Med.  Yes   Good  High  High  Med.  Low  Med.  -70°-160°
Vulcalite ™
-AR
Low
Low
Yes
Very Good
High
Med.
High7
Low
Med.
-70°-160°
Versa-Tech®
-TE
Low
Low
Yes
Very Good
High
Med.
High7
Low
Med.
-40°-180°
Ace-Tuf®
-AT
Low
Low
Yes
Good
High
High
High
Low
Low
-10°-160°
Pneumatic
-PR
Low
Low
Yes
Good
High
High
Med.
Low
High
-30°-120°  

1 Chart is intended only as a general comparison, and not as a recommendation for any particular wheel in a specific application. Unusual conditions may require more detailed consultation with factory. 2 On smooth floors without obstructions. 3 Excluding marking or staining (depending on type floor). 4 Fahrenheit. The ranges shown should be used only as a guide since wheel life, capacity and/or performance generally decline at elevated temperatures depending on length of exposure, etc. Not all bearing types will be suitable throughout the ranges given. 5 Steeltest Ductile Alloy or Forged Steel are available for higher impact resistance. 6 Extra-hard 90-durometer compound for higher capacity available on special order. 7 Neoprene oil-resistant compound should be specified for oily conditions. 8 Special high-temp compound available-consult factory.