What is a Caster and where are they used?

Look around casters are every where there is rarely a industry that doesn't used casters and wheels in some aspect. Hospitals, grocery stores, offices, industrial plants, delivery and warehouses, laboratories, industrial plants & your home, just to name a few. 

A caster (or castor) is an un-driven (non motorized), single, double, or compound wheel attached to a swivel or rigid caster fork. They are designed to be mounted to the bottom of a larger object, like a cart, dolly, display, furniture or equipment, so as to enable that object to be easily moved. They are available in various sizes, and are commonly made of steel, rubber, polyurethane, plastic, nylon, aluminum, or stainless steel.
Casters are found in numerous applications, including shopping carts, office chairs, and material handling equipment. High capacity, heavy duty casters are used in many industrial applications, such as platform trucks, carts, assemblies, and tow lines in plants. Generally, casters operate well on smooth and flat surfaces. There are options like pneumatic casters that are air filled that will work well on all surfaces and absorb bumps and cracks.

There three most common casters types are as followed...

Rigid Caster                             Swivel Caster 

Rigid Casters: A wheel mounted to a stationary fork with an axle and nut that allows the cart or equipment to roll but will restrict lateral movement.

Swivel Casters: Similar to the rigid in that it is a wheel mounted to a fork, but the swivel will have a pivot to allow the wheel to rotate freely to help with movement and steering.

Locking Caster: Locking casters are usually but not always swivel. These casters are equipped with a brake mechanism to prevent the wheel from rolling when activated.

Anatomy of a Caster

Purchasing the proper casters and wheels can sometimes
be daunting. Are you looking for swivel casters or industrial casters is there a stem or a top plate. There are certain terms used by the  industry to describe parts of the caster itself. So whether you are replacing you casters on your carts and dollies or you shopping carts or equipment, or have a new project that needs casters and wheels, Buy Casters can help and hopefully this blog will be educational.
This guide is designed to help you with those terms and hopefully this can help you make a good decision on the caster that is right for you.

Pictured is a caster "Yoke or Rig" with a top  plate mounting style. 

1. King Bolt
2. Rivet or Kingpin 
9. Thrust Race
12. Thrust Bearings
13. Button
14. Nut
These attach the caster legs to the top plate.
For a stronger option there is a kinpinless model.
3. Mounting Bolt Holes
Holes for the bolts to mount the casters.
You will need to know the spacing of these to determine proper fit.
4. Top Plate
The top plate it the mounting bracket, there are various sizes and styles, stem mounted is another option, 
which is a post. Threaded stems, grip ring stems and 
expandable adapters are the most common styles.
5. Load Race
6. Load Ball Bearings
7. Yoke Base
These are all components of the swivel mechanism, better components here will allow for greater weight capacity and smoother swivel action.
8. Zerk Fitting
A zerk is required for greasing the bearings in the race way higher quality casters and heavy duty casters would have a zerk fitting.
10. Legs
The size of the legs determine the size wheels that can be used in the caster, also the legs will be fitted with a slot for mounting a brake to turn it into a locking caster.
11. Axle Hole
The axle hole on the caster legs are specific sizes determined by if the caster is light duty, medium duty or heavy duty. 1/2 " axle is the most common but other sizes are available.

These are just a few of the common terms used when describing a caster. Interested in learning more or finding casters to aid in your project? Visit buycasters.com or contact us at 1855-WHEEL11.