Castor wheels or casters are smaller wheels that one can mount under a piece of equipment or an apparatus to make the object movable. This alteration is done for the workers’ convenience or improving a particular work area’s productivity and time effectiveness. One can affix castor wheels onto beds, furniture and shopping carts; the cart being the most common. Casters usually don’t move unless driven and commonly consists of a single wheel and bracket. They consist of rubber, or plastic compounds with nylon and industrial-grade casters are made of metals like stainless steel and aluminium to increase strength and longevity.
Types Based on Fixtures
Plate Fixture: Consists of a castor wheel mounted with a flat multi-holed plate’s help and can be screwed onto another flat surface.
Stem Fixture: Consists of a threaded projection that one can attach to the object or a clip that can be locked into the surface with a screw or a clasp.
Based On Mobility
Swivel Type: The design of these casters aid the wheel in rotating to any direction under a certain weight. This rotational movement allows the caster’s centre to move clockwise or anticlockwise, making the equipment or object to turn fairly quickly.
Fixed Type: These rigid castor wheels don’t employ rotating brackets. There is only a wheel inside an immovable frame, and thus, these types of casters are most suited for translational movement of the equipment, and no turning is possible. Since there is no strength loss in the addition of a movable joint, fixed type casters can handle a much higher weight than swivel types.
Applications
- Shopping carts
- Types of Furniture
- Heavy Equipment for industrial applications
- Aerospace Industries
- Hospital beds
Types Based on Design of Castor Wheel
Plain Surface: These types of castor wheels have a plain surface and allow smooth movement.
Rounded Surface: The casters’ surface is curved or rounded to resemble the surface of a ball. One can usually find these in Omni-directional casters.
Flanged Surface: Consists of an inner groove and regularly used on top of steel tracks for heavyweight loads; usually made of stainless steel or aluminium.
Based on Material
Steel: Stainless steel, semi-steel, forged and ductile steel are some of the steel casters’ variants. One can use steel casters in areas with high temperatures, and where increased physical strength is required. These castors also have higher load capacity, which can withstand more load than other materials.
Rubber: They are either made with a whole rubber wheel or rubber coating the aluminium or cast steel wheel. Since rubber is more resistant to chemical corrosion and other agents, it allows smooth movement. Rubber fixed on metal surfaces offers more friction on plain surfaces and at the same time, the strength to withstand heavy loads.
Nylon: They are the most common of all castor wheels. They are used either with glass or other packing materials and are employed in rotating chairs or furniture brackets.
Phenolic: These wheels offer higher resistance to temperatures and are more affordable for industrial applications than most metals.
Polyurethane: These wheels are fused with polymers like polyolefin to provide further chemical resistance and more durability than most metals. Pneumatic and Semi-Pneumatic: These wheels either contain regular air or a mixture of air with other compounds which lends more strength to the wheel. These wheels can roll over most obstacles and are used extensively in aerospace.