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.