There are a few things to know before you begin shopping for casters. First, you’ll want to consider the bolt-hole spacing. This is the distance between the bolt holes, typically 1 3/4″ to 2 7/8″ apart. These measurements are not adjustable, so you’ll want to know them before purchasing a caster. Next, you’ll want to consider the wheel size, determined by two measurements: the wheel’s diameter and the hub’s width.
Material of Caster
Casters come in many sizes, depending on the application. Typical applications include medical, food service, and manufacturing. Each caster has a top plate that fastens to the object intended to move. When buying new caster wheels, measure the top plate to determine its exact size. Or, to get a central idea of what size to buy when replacing an old caster, measure the top plate that is already there.
Another factor in determining caster size is the type of floor. For example, soft carpets require larger-diameter casters, while smaller ones can roll smooth feet. While smaller casters can carry the same load as larger models, they can also be more challenging to move continuously. Other factors to consider when choosing casters include the category. For example, soft tread casters are better suited for smooth surfaces, while rigid tread casters work better on hard surfaces.
Choosing the proper casters for your application will require some considerations. Firstly, you need to know how heavy your equipment is and its weight. Then, you need to know how much load your casters can safely handle. You can also choose between different load capacities and finishes for your casters. For example, a low-load capacity caster will be easier to steer than a high-load capacity one.
Next, you should measure the wheel diameter of the casters. The diameter of the wheel should be about three-quarters of the height of the load. Again, you can measure this with a caliper.
Hub width refers to the width of the part of the hub that is in contact with the wheel’s frame. The width of the fork and the structure should correspond to this measurement. Offset hubs extend over the side of the wheel and have a wider width on one side. Hand trucks and other equipment with axle bars frequently have offset hubs. In either case, the wheel will protrude over the side.
Hub length is the distance between the outer edge of the wheel and the hub bore. The proper length is essential in ensuring that the wheel fits without too much play. The right length also helps ensure the wheel fits appropriately onto the frame or fork. In most cases, a tape measure will not fit through the bore, but you can use a dowel or pencil to get a close estimate of the length of the hub bore.
When purchasing casters, you’ll need to know the swivel radius of the objects you’re moving. This measurement is made by placing a straight edge against the measuring device. If the radius exceeds the required number, the casters can only complete a partial 360-degree rotation.
Swivel radii are measured from the center of the kingpin to the trailing edge of the wheel. This measurement is easiest to measure if the caster is lying on its side. First, line up a straight edge with the edge of the wheel and hold it up to the measuring device.
You can also measure the diameter of the stem of the caster with an adjustable wrench. Again, use a twist without brass bands or wire rings. The gap between the jaws should be at least three-eighths of an inch.
To find out what size casters you need, calculate the weight of your moving equipment. Then, divide that total weight by the number of casters. Each caster should be able to hold at least 250 lbs. of load. This calculation is necessary because the load capacity of your casters may be affected by uneven load, shifting, and impacting objects. Load capacity is a measurement of the total weight of the transport equipment and the load it carries. The bag’s total weight is divided by the number of shipment-bearing casters. For example, if you have four casters, subtract one from each. However, this data is based on standardized test conditions, so it may not hold up on uneven floors or extreme temperatures.