Industrial Casters & Caster Wheels

Types of Industrial Casters

Plate Casters

When shopping for plate casters, there are two main types to keep in mind: swivel casters and rigid casters. Each type of caster has its pros and cons.

Both fixed and swivel casters have bearings in the wheel that let them move the wheel back and forth along a path. This movement can be used to turn the wheel or put force on the load to move it up or down. On fixed casters, this force is applied by a bearing that is mounted on the inside of the caster. In a swivel caster, a ball bearing is mounted to the outside of the wheel within the “raceway.”

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There are many ways in which rigid and swivel casters are not the same. On the one hand, both are very easy to move even though they are heavy, but a rigid caster can only move in a straight line.  Also, the wheels on a fixed caster can’t turn in a direction that is parallel to the wheel path. To their credit, though, they do have locking mechanisms that make them very safe. So, in this case, rigid casters have a slight edge over swivels. A swivel caster is a way to go if you want to move something with a heavy load.

Swivel Casters

There are a few things to think about when deciding between a rigid caster and a swivel caster:

  1. What’s the size of your equipment?
  2. Does it only have to go in a straight line?
  3. How much does it weigh?
  4. Does it need a way to lock it?
  5. How wide is the equipment and how big is the size it’s in?

As was already said, swivel casters offer things easier to move around. Because of this, people who need casters for industrial or commercial uses may find them easier to use. But not every need is the same. Each of these designs is easy to carry in a different way. When choosing casters, you should offer sure they will fit in the space you have and that they are flexible enough to meet your specific needs. You can shop for thousands of casters online, both for industrial and home use. When you find something you like, we’ll send it right to your door.

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Stem Casters

On our website, you can find a wide variety of heavy-duty casters. The stem caster is a great choice if you want casters that are easy to install and replace. It does, however, come in different kinds that depend on your needs and how you want to use it. Stem casters have a long stem that can be inserted into a table, chair, or any other object with enough space to insert a hole for the stem.

There are many kinds of stem casters: threaded stem casters, grip ring stems, grip neck stems, expanding rubber stems, and square and round stems with cross holes for your wire shelving.  If you need help finding the right casters for your job, we can help you.

Get in touch with our support team if you need more help finding the right casters. We have dedicated experts with years of experience who will give you the best advice in the industry.

Threaded Stem Casters

With a threaded stem caster, there are two ways to install it: either you need to install a threaded insert so you can screw the threaded stem caster into the insert, or you can tap a hole into the equipment.

If you can get to the other side, you can also drill through something. Then, you can put a lock washer and lock nut on the threaded stem caster and tighten it with a wrench. This is a good choice if your base isn’t too thick, and you don’t have a place to install the threaded insert for your heavy-duty casters.

Pipe or tubing frames are one of the most common ways to use threaded-stem casters. The lock nut makes it very useful because you don’t have to install it in any kind of insert. Instead, you can just drill a hole where you need it.

Determine what your requirements are so you can use them to find the right casters for your job.

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Grip Ring Stem Casters

Grip ring stem casters can be used for a lot of different things are mostly used for chair and furniture applications.You should use grip ring stem casters when you won’t be picking up furniture or other equipment and gravity will keep everything in place.  If a force were to pull on the caster it could come loose from the socket.

When you can’t get to the back of furniture or piece of equipment where you want to install casters, like on long wooden legs or thick plastic, grip ring stem casters are the best choice.

Inserts for the grip ring stem caster can be made from almost any material, like wood, welded inserts, PVC, metal, or plastic. If you need a heavy-duty caster but can’t reach the back to put on a lock nut, a grip ring stem caster is your best bet.

You’ll need to figure out your requirements and then use those to determine the right casters for your job.

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Measuring the Stem

If you have a caliper, measure the Grip Ring Stem in the part below the ring that is closest to the caster body. If it measures .437 + or –, the diameter is 7/16″. If it measures between .375 + or -, it has a diameter of 3/8″. You don’t need to use another way to measure!

People often have trouble measuring the grip ring stem (also called the mounting post) on their chairs or furniture casters accurately. The “grip ring” is the c-shaped metal clip that fits into the holes on the bottom of the chair and squeezes together. It keeps the caster in the hole. If you want to replace a caster that has a “grip ring stem,” first try measuring it with a ruler. Place the ruler across the middle of the length of the stem (not near the top of the ring). Most casters with a grip ring stem have a 7/16′′ stem diameter. If your caster’s stem is 7/16′′ in diameter, it will be just under the 1/2′′ mark on the ruler. The only other diameter of the grip ring stem is 3/8′′. On a ruler, 3/8′′ is in the middle between 1/4′′ and 1/2′′. If your Grip Ring Stem is 3/8″ in diameter, we’re sorry, but we can’t help you. We only sell chair and furniture casters with Grip Ring Stems that are 7/16″ in diameter.

Second, you should try one of the following to double-check your work:

Please use two of our methods to measure the stem diameter. Remember, measure twice – order once.

Now that you know how big the stem is, you only need one more diameter: how deep the hole is. For the replacement caster to work, the hole in the chair must be the same length as or longer than the stem of the caster. A pencil is an easy way to measure how deep the hole is. Insert off an old caster, put the pencil in the chair’s hole, and mark the depth with your thumb. Take the pencil out and measure.

How To Install Stem Casters ?

If you need to replace a caster, take it off first so you can measure its length and diameter. That way, you can use the same stem without having to make any changes. You don’t have to try to install a new caster insert again, which will make your life much easier.

Installing Grip Ring Stem Casters :-

  • Remove the old caster, determine its size and diameter, and put on a new heavy-duty caster with a grip ring in its place.
  • You might need pliers to get the old caster out of the socket or insert.
  • Take your new caster and push it with some force into the grip ring insert or socket. If the sizes are right, it should just snap into place. If needed, use a small amount of lubrication on the stem.
  • Make sure that a light pull or shake on the grip ring stem caster doesn’t cause the caster to fall off.

Installing Threaded Stem Casters :-

There are two ways to install threaded-stem casters. You can either screw them into a threaded insert or put them through a hole and use a lock nut to hold them in place.

Stem casters are easy to install on and take off. You can easily replace the caster without having to replace the insert, which helps keep your equipment in good shape or if something breaks. If you did everything right when you first installed the stem casters in place, the job can be done quickly.

Threaded Stem Casters with Lock Nuts :-

  • Take off your lock nut, lock washer, and threaded stem caster. Determine the diameter because the length shouldn’t be a big deal unless something is going to go over the top.
  • Put your new threaded stem caster through the hole, then put the lock washer and lock nut on top and screw them in. You can tighten the threaded stem caster into place with a wrench or another tool.

Industrial Caster Parts & Pieces

There are several working parts to an industrial caster including:

  • Top Plate/Stem
  • Inner raceway
  • Outer raceway
  • Ball Bearings
  • Fork
  • Axle Bolt
  • Top Hat Bushings
  • Axle Nut
  • Lock
  • Wheel

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If you need a new part, or you’re looking for spare parts, contact us and we can help you find the right ones.

Caster Wheels

Polyurethane

The tires on these caster wheels are made of polyurethane and were injected into a polyolefin center. They don’t leave marks. They are especially suited for use in research labs, hospitals, schools, bakeries, and other institutional applications. On smooth floors, these wheels are easier to move than Gray Rubber wheels. They can handle being around a lot of chemicals and solvents. They can be used in industrial applications that don’t involve shock, overloading, abuse, obstructions, bad floors, or storage (standing) loads.

Nylon

Nylon caster wheels are made with solid nylon material. Black Nylon Caster Wheels are reinforced with glass fiber to increase capacity and reduce friction when rolling. Select Nylon Wheels can come with either stainless bearings or a plain bore for applications in which wheels are exposed to:

  • Wash Down
  • Steam Cleaning
  • Salt
  • Brine
  • Blood
  • Chemicals
  • Cleaning Solutions
  • Organic Solvents
  • Oil
  • Grease

Even though these wheels are very light, they can carry about the same capacity of load as most metal wheels and will not flat spot. Nylon wheels are a better choice for use in wet and corrosive applications where chemical resistance and a higher load capacity are needed.

Not recommended if your solution has more than 10% acidic content.

Rubber

The tires on rubber caster wheels are made of grey thermoplastic rubber that was injected and then mechanically bonded to a polyolefin (an industrial plastic) center. They are often used on equipment in Pharmaceutical Laboratories, Hospitals, Food services, and other Institutional applications. These caster wheels are softer than polyurethane and offer a quieter ride.  They can be used in industrial applications that don’t involve shock, overloading, abuse, obstructions, bad floors, or storage (standing) loads.  The RH wheels can hold a little more capacity than our other grey soft rubber wheels.

No other wheel material works better than soft rubber when it comes to how it moves. Our soft grey rubber wheels don’t leave marks, are quiet, absorb shock (which protects cargo and extends the life of the equipment), can roll over small objects, protect expensive floors, and reduce vibration. They are not perfect because they are not easy to roll when they are full.

Ratings of load capacity don’t consider how hard it is to move a load by hand (drawbar pull measured in pounds). If you want to move things by hand with these grey soft rubber caster wheels, cut the capacity ratings in half and choose the largest wheel diameter you can. You shouldn’t leave these caster wheels standing with a load on them for long periods, because the tires may “set” or get flat spots. Almost any dry factory floor can be used with them. The glue that holds the rubber tire to the polyolefin center can break down if it is exposed to certain chemicals, hit, overloaded, or heat builds up.

Metal ( Iron & Steel )

Iron

These grey iron wheels are cheaper than wheels made of ductile or forged steel. They are useful for carrying light loads on wood blocks or smooth, hardened concrete in applications where they won’t be abused. On concrete floors that haven’t been treated, they tend to damage the floor quickly. Ductile, Forged, or Machined Steel wheels are the only ones we recommend for applications that might be rough on the wheels. Abuse includes things like shock loads, impact, bad floors or floor obstructions, overloading, and using it with mechanically powered equipment.

Steel

When loads are too heavy for floor-protecting wheels or when service conditions are unusually harsh, forged steel and ductile steel caster wheels will do the job. Most of the time, the user won’t think of floor wear as a big problem in these applications because of the work that is being done. Most factory floors can’t handle forged steel caster wheels, so they are usually used on steel plates, in channels, or as V-groove wheels on an angle iron track.

Caster wheels made of forged steel and ductile steel have high ductility and tensile strength, so they can take shocks and hits without breaking. In normal use, these solid (no spokes) wheels can’t be broken. Their load ratings are only limited by how much capacity they can hold.

Caster wheels made of solid hot-rolled steel bars are called “machined steel.” They can handle shock loads very well and have a high capacity, durability, and performance. You can choose between a 3/4-inch ID bronze bearing or a 3/4-inch ID roller bearing. Both wheels come with a 1/2′′ ID Spanner Bushing so that they can be put on a 1/2′′ caster axle.

Depending on the use, these steel wheels can handle temperatures up to 700° F. Steel roller bearings and spanner bushings can start to anneal at temperatures above 400°F that stay the same for a long time. For applications where temperatures are higher than 400° F, please talk to our engineering department.

2″ wide Roller Bearing wheels come with Combo washers that make the Hub Length 2 7/16″ so that it can fit into a caster bracket.

Polyolefin

Polyolefin Caster Wheels are made by injecting a mixture of thermoplastic polymers into a mold to make a solid, sanitary design that is all one piece. Like Nylon wheels, these Polyolefin wheels are especially suited for wet and corrosive applications. They are very resistant to most liquids you might come across. Except for our extra heavy duty polyolefin wheels, Polyolefin wheels can’t carry as much capacity and can only be used in a smaller range of temperatures than Nylon wheels (prefix RK). Polyolefin wheels can break if they are kept in a cold, dry place, like a cold storage room. They shouldn’t be used in a freezer or with intermittent heat above 180°F, like in a rack washer.

Our Extra Heavy Duty Polyolefin Caster Wheels (prefix RK in the part number) are reinforced with glass fiber to increase their capacity. The load capacity of these Extra Heavy Polyolefin wheels is the same as that of Nylon wheels. They also work well in wet and corrosive environments. Extra Heavy Duty Polyolefin wheels come standard with Non-Stainless Precision Sealed Ball Bearings (PS) and Stainless Precision Sealed Ball Bearings (SPS).

Industries

Automotive

  • The Extra Long Lead (offset) is standard. Reduces vibration and noise in a power towed application and allows the swivel caster to turn more easily when moved manually.
  • For slow-speed manual or power towed applications on smooth floors with no obstructions or shock loads.
  • Non-marking polyurethane tires with high performance.
  • Ergonomically designed to reduce the force required to start and maintain the equipment.
  • Easier rolling and turning improves safety by lowering the risk of employee injury.

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RV & Motorhomes

  • Secure to the back to protect your equipment.
  • Designed to roll slowly even on curves.
  • To extend caster life, creep slowly until the wheel contacts the ground.
  • We recommend only rigid casters for this application because swivels are prone to breaking if not facing the direction of travel.
  • When making a turn on a curve, there may be a scraping action that will harm the tire.
  • Tires degrade over time. Replacing just the wheel is less expensive than replacing the entire caster.
  • Use a ductile steel wheel that will slide along the top of asphalt versus gripping and ripping the wheel off of the caster bracket

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Science & Medical Labs

  • Our casters are built to withstand the high impact forces of cage and rack washdown machines.
  • Polyurethane provides floor protection and long life when used with wash down flooring or grating.
  • Solid Delrin bearings, Stainless Steel Precision Sealed Ball Bearings, or Stainless Roller Bearings are available for wheels.
  • A wide range of stem options to suit your application.
  • High-polish stainless steel casters are available; please call for availability.
  • If your stem caster capacity requirements exceed 300lbs per caster, please contact us for a recommendation.
  • We manufacture stainless steel casters that can support up to 5000 pounds each – contact us by phone or email for more information.
  • Only 4″ and 5″ diameter Welded Disc Polyurethane Wheels are available.

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Choosing the Right Caster

Determining Load Capacity

There are a wide variety of industrial casters available, each with a different load capacity. That load capacity is a measurement of how much weight the wheel can handle while rolling. If you overload your casters, it can result in premature failure of the industrial product or damage to floors.

How To Determine Load Capacity of Your Industrial Casters?

When purchasing industrial strength casters, the exact load capacity per caster should be examined and documented for future reference.

For industrial casters, there are three standard capacity levels:

  • Light duty casters can support loads of up to 500 lbs.
  • Industrial casters begin to support loads of up to 2000 lbs.
  • Heavy-duty industrial casters are required for loads weighing more than 2000 lbs.

Individual load capacity for your casters isn’t what needs to be calculated; you need to determine the maximum load you want to move, add it to the weight of the cart or equipment doing the moving, and then add 33 per cent on top of that for a safety buffer.

Once you’ve determined your total weight, divide it by the number of casters that will be on your equipment to determine the minimum load capacity for each caster you’ll need to purchase.

If you want to move 2000lbs on a 100lb cart with four wheels, you’ll need four casters that can handle 699lbs each, and if there aren’t any casters that can handle that exact figure, you’ll need to buy up to the next highest caster load capacity.

Why Add a Load Capacity Buffer for Industrial Casters?

Adding a 33% safety buffer to the load capacity of your industrial casters may incur additional costs, particularly if rounding up relatively high.

One issue with determining caster load capacity is that it is the maximum in ideal conditions. Non-continuous operation or load on smooth floors at speeds under 3 mph are ideal environments for industrial casters.

If your environment and caster usage aren’t ideal, the safety buffer is a low-cost way to ensure worker and product safety. If this is the case for you, please contact us directly and we will assist you in deciding.

What Factors Determine Load Capacity on Industrial Casters?

The load capacity of industrial casters can be determined by a variety of factors; understanding what and how each component determines the load capacity will help you determine the right caster for your job.

You’ll see below that each factor can have a significant impact on load capacity on its own, which means you can factor in your requirements and find the right caster that gives you the most benefits rather than just picking one factor to increase load capacity.

If you’re unsure about the requirements or which casters will be best for your project, give us a call and we’ll be happy to assist you! All casters sold by our in-house team of specialists are guaranteed.

Caster Wheel Diameter

The diameter of the caster wheel is an important factor in caster load capacity. The larger the diameter of the caster wheel, the more weight a caster can support overall.

For example, if everything else is equal on the same branded caster, the load capacity increases nominally with the caster wheel diameter as follows:

In general, a 2″ increase in caster wheel diameter results in a steady increase in additional load capacity. You also get larger diameter wheels, easier maneuverability, and the ability to handle rough surfaces more easily.

However, you should check on specific products because there may be other differences that impact load capacity.

Caster Tread Width

A wider caster wheel tread has a larger load capacity than a thinner caster wheel tread. If you take the heavy-duty casters with a 3″ tread width and reduce it to 2.5″, the load capacity decreases.

  • The load capacity of 6″ heavy-duty casters with 2.5″ tread is 1,500 lbs.
  • The load capacity of 8″ heavy-duty casters with 2.5″ tread is 2,000 lbs.
  • The load capacity of 10″ heavy-duty casters with 2.5″ tread is 2,500 lbs.
  • The load capacity of 12″ heavy-duty casters with 2.5″ tread is 3,000 lbs.

As you can see, even a small decrease in caster tread width has a significant effect on caster load capacity. This also allows you to work around height restrictions by increasing caster tread rather than caster wheel diameter to increase load capacity.

Caster Tread Profile

A caster tread profile can impact load capacity; you can choose between a rounded or flat tread profile. Casters with a flat tread profile will last longer and support a higher load capacity by distributing the load over a larger surface.

Casters with rounded tread profiles, on the other hand, have superior maneuverability and roll much easier. So, depending on your future budgets and maneuverability requirements, you’ll need to select the best caster tread profile for your requirements.

For example, using the same industrial-strength casters, the load capacity varies significantly between flat and rounded tread:

  • The load capacity of 6″ heavy-duty casters with rounded tread profiles is 450 lbs.
  • The load capacity of 6″ heavy-duty casters with a flat traditional profile is 600 lbs.

Another significant difference in load capacity with the same type of casters.

Soft Industrial Casters vs. Hard Industrial Casters

Soft casters are typically quieter and more maneuverable when made of materials such as polyurethane but have a much lower load capacity when compared to hard casters made of materials such as steel.

Most manufacturers will use hard material for extreme industrial strength casters and soft caster materials for lighter and more delicate environments.

If you want to check more about casters, you can do so by visiting our blog.

Tips on Choosing the Right Caster Wheel

In our opinion, you are not purchasing a simple wheel or caster. You are purchasing a product that must function properly for you. Internal material handling is an expense. Wheels and casters that are properly designed can help to reduce this cost.

Productivity

The productivity of equipment and the people who use it is affected by wheels and casters. Selecting the right wheel or caster ensures maximum productivity, lowers long-term costs and provides the best return on investment.

The heart of any piece of rolling equipment is its wheels. Bearings propel wheels, influencing production. Low-grade tires and bearings do not provide profitable performance, particularly when adapted to heavier loads or powered operation. Their use necessitates costly maintenance, out-of-service equipment, and multiple manpower to move when no power is drawn.

Safety and Ergonomics

The high drawbar or resistance of equipment to move causes injury and health hazards when using manual equipment. Select casters and wheels that, to the greatest extent possible, eliminate the possibility of injury and health complaints associated with excessive strain.

When selecting a wheel or caster, keep your employees’ safety and well-being in mind. A human must move the equipment in a manual application. The larger the diameter of the wheel, the easier it is to roll. The proper tire design and composition also have an impact on your employees’ performance and health.

Ergonomic casters and wheels reduce the possibility of work-related injuries. They reduce absenteeism while increasing worker productivity and efficiency. Ergonomically designed features reduce sources of physical stress and tension, allowing any employee to work comfortably and safely. Swivel casters with precision swivel bearings are one example. This feature allows a swivel caster to turn more easily while under load, reduces starting effort and fatigue, and allows for more consistent output. When you consider safety and ergonomics, you reduce lost time due to accidents.

Floor Protection

Repairing or replacing floors is an expensive endeavor.  Poor floors harm castered equipment, reduce productivity, and endanger personnel. Selecting the most appropriate floor protective wheel for your application will protect good floors and reduce the rate of wear on floors that are already deteriorating. Only wheels with a soft rubber tread protect the floor and cargo. These include PREMIUM, SUPER CUSHION, Conventional Mold-on, Pneumatics, and Gray Rubber wheels. A common mistake is to think polyurethane wheels are floor protective. Although under load they are capable of some tire deflection, actual “tire give” is rarely noticeable. Most polyurethane wheels have a hardness comparable to “hard tread” wheels (phenolic, polyolefin, hard rubber), but are not as noisy. The “Jack Hammer” action of hard tread wheels is destructive to most floors with time. However, even metal wheels fill an important need when the operating environment or capacity prohibits the use of anything else.

Rollability

Remember that a human being must move the load, so select the largest wheel your application will allow. Load capacity ratings do not consider the effort required to manually move the load. Conventional mold-on rubber wheels are not easy to roll. We recommend you reduce the weight to no more than 50 per cent of their rated capacity if the load is to be moved manually on soft rubber wheels. Polyurethane and “hard tread” wheels are only easy rolling if you do not exceed the load capacity of the same size rubber wheel, and then only if the floors are smooth. They are not easy rolling when loaded to their full rated capacities. PREMIUM rubber wheels when loaded to full capacity can be moved manually. As long as your loads do not exceed the rated capacity of PREMIUM rubber, its selection means you will not have to give up the benefits of resiliency (floor and cargo protection) to get rollability.

Capacity

Selection should never be made based on capacity alone. Capacity ratings on this website are based on intermittent use at a speed not exceeding 3 mph over smooth floors in a manual operation under ideal conditions. Your conditions are seldom ideal, so select a wheel or caster with much higher capacity than the weight you require. Always consult us first for a reduced capacity rating if the wheel or caster is to be used in a mechanically powered application. Capacity ratings are offered as an idea of what the wheel or caster will carry without failure. They are not absolute, but rather depend on the usage and service. Capacity ratings shown do not allow for shock loads, overloading, abuse, obstructions, or poor floors. Proper maintenance requires all bearings to be relubricated on a regular schedule, and all bolts and nuts to be kept tightened. Conditions of excessive temperature, dirt or other contaminants will reduce capacity and minimize performance. The temperature range shown for wheels in this catalog is the range of the wheel material. Operation near either end of the temperature range may require a substantial reduction in capacity or cause a wheel to be unsuitable for the application.

Floor Obstructions and Operating Environment

Sometimes obstructions must be tolerated. Examples may include expansion joints which are not level, track, dock plate, or brick floors. There simply may not be an ideal solution. However, generally, resilient wheels roll over floor obstructions better than hard tread wheels. Obstructions require selecting larger wheels and stronger casters than the application would require if the floors were smooth. Metal shavings can become embedded in rubber and polyurethane tires. Steel plates can cut resilient tires, and chip or break hard tread wheels. Always keep floors clear of debris. Harmful substances or chemicals may require using special wheels or bearings. The bonding agent which holds rubber and polyurethane tires to their metal centers can be affected by exposure to some chemicals, impact, overloading, and the buildup of heat. Stainless Steel casters are made with 304 Stainless Steel which is rust-resistant. In some severe applications over time, Stainless Steel 304 may rust.

Cost/Value Analysis

Too often the purchase of wheels and casters is based on criteria far removed from the essential purpose – “Will they move the load smoothly and easily?” A piece of equipment purchased to carry and move a 2,000 lb. load is costly when it is loaded with only 1,000 lbs. to roll. Most people will load equipment only to a weight they can move easily and without injury. Equipment that requires two men to move it, when one should suffice, is also an expensive unit, regardless of acquisition cost.

Old style casters and wheels are usually built to a price, with no consideration of their investment value for profitable operation and payback in productivity. Our products are competitively priced but look beyond the price tag. The initial cost is a factor in a purchase decision, but it is only one factor.

Consider making a value analysis, it may bring out some other factors worthy of consideration. Value rate the product. A human being must push or pull castered equipment. Ease of rolling and wheel life are the two important elements of an efficient and economical manual operation. Sometimes a certain caster or wheel may not be the least expensive choice if you are looking at only the initial cost of acquisition. However, if it is the right caster or wheel for a particular application, the cost will be commensurate with the value and the payback.

Ask yourself to what extent will a caster or wheel require maintenance? The cost of acquiring a product should be weighed against the cost of keeping it in operating condition. Bearings and their service generally are the largest factor in maintenance. The cost of systematic lubrication and replacement can be a drain on profits; if one is neglected, the other increases.

Will the caster or wheel further dependable operation? With an easier rolling wheel and easier turning swivel, employees tire less, there are fewer accidents and productivity increases.

Our Staff can give you valuable assistance in the selection of the right combination of wheels and casters for your needs. They are knowledgeable, qualified, and experienced in caster usage.