What Is A Durometer?

While looking at casters and caster wheels, you may have come across the terms “Durometer” or “Shore Durometer” and an associated number and letter. What do they mean? Where did they come from? Why are they there? Read on to find the answer to these life-changing questions.

Let’s get the confusing part out of the way first. Durometer is both a measurement and a tool for measuring. In other words, you measure the durometer of an item with a durometer.

But what exactly is a durometer measuring? The hardness of an item. There are many durometer scales represented by a letter(in the caster and wheel industry we use Shore A and Shore D)  ranging in numerical value from 0-100. The higher the number, the harder the item is on that particular scale. For instance, a rubber band has a durometer of 25 A. Skateboard wheels (or many of the polyurethane wheels we sell) might be between 85-95 A. This doesn’t mean that they are extremely hard, just that they are one of the hardest materials the Shore A scale can measure.

What happens when an item is harder than the Shore A Scale can measure? That’s when we move on to the Shore D scale. Any of our harder wheels, such as a phenolic resin wheel, will be measured on the D scale. A phenolic resin wheel has a durometer of 90 D. Another example of an item on the D scale would be a hard hat, which has a durometer of around 75 D.

Ultimately, the durometer of a wheel can help the user figure out how the wheel will react to its environment and the floor it is on.  Will it be durable enough? Will the wheel damage the floor? Will the floor damage the wheel? Will the wheel roll over debris? These questions can be answered (or at least approximated) through the use of durometer measurements.

Is Stainless Steel Non-Magnetic?



Over the years, we’ve had a few people contact us in regards to our stainless steel casters. “Hey!” They say, “You’ve sent me the wrong casters. These are supposed to be stainless steel, but they’re magnetic.” We understand the concern, but have no fear… magnetism and stainless steel are not mutually exclusive. For example, stainless steel kitchen knives are often magnetic.

There are various types of stainless steel with a range of magnetic properties based on the atomic structure of the steel. Without getting too complicated, chromium content is what gives the steel its stainless properties. Sometimes, other materials are added to give specific attributes to the steel such as malleability or hardness. One such added material is nickel, which when combined with the steel creates the non-magnetism.

Our most commonly sold stainless steel casters are made with ferritic stainless steel, and they are magnetic. Some applications, such as MRI machines or special lab equipment, must have non-magnetic steel. If this is the case for your application, please give us a call at 1-800-215-8220 to discuss more options.



Twin Wheel Casters VS. Single Wheel Casters

One question we get a lot here at SCC is, “Why choose a twin wheel caster instead of a single wheel caster?”

A twin wheel caster offers several distinct advantages over its single wheeled counterpart. Perhaps the most obvious advantage is weight handling capacity. If we take two casters with the same wheel diameter and material, but one is twin wheeled, it will handle more weight. Another way to look at this advantage is that we can use a smaller twin wheel caster to reach the same weight bearing capacity as a larger single wheel. This can be important if you need to maintain a lower load height within a specific weight capacity range.

Another great feature of twin wheel casters is their ability to turn easily. Where a single wheel caster must pivot on itself, a twin wheel caster’s wheels can rotate independently of each other, making turning or reversing direction much easier.

For more information on using twin wheel casters, give our customer service team a call at 800-215-8220 and we’ll be happy to help you out.

Chair Casters for Carpet

Carpet is very common and casters can be used on anything from low ply to shag carpets, but the types of casters used will vary.

For a low ply carpet, any hard wheeled caster will do the trick. Nylon, hard rubber, or other hard material will work well for the wheel. These materials will grip the carpet less than softer materials, making it easier to turn and roll. A rubbery material will grip the carpet, and feel like its sticking when they are moved.

For a shag or thick carpet, not only should a hard wheel material be used, but also the largest diameter caster wheel possible. Many times a large wheel is not desired, but the largest one possible should be used in this cast to prevent the caster from binding up in the carpet.

Many chair and furniture casters can meet these demands, so be sure to discuss your carpet type and options with a caster and wheel representative by calling us at 800-215-8220.

Caster Wheels for High Temperature Environments

Most casters and wheels for industry and commercial applications contain some ability for exposure to temperatures above the norm. Typically, temperatures to 180 degrees Fahrenheit are possible. For those environments where higher temperatures are expected, such as a bakery oven or autoclave, caster wheel composition must be considered.

Recommended exposures to high temperature and length of operation vary. Also, consideration to the type of heat is necessary. These factors, along with floor surface, determine the possible lifetime of the caster wheel.

For locations with a dry heat, high temperature Phenolic wheels perform optimally. A safe range for estimating usage would be temperatures up to 475° F for 30 minutes of continuous operation.

When moist heat is expected, a glass-filled nylon wheel for high temperatures is the favored option. Conservatively, 475° F for 30 minutes continuous use provides the best scenario for a prolonged wheel lifetime. It should be noted that glass-filled nylon wheels are not for use in dry heat.

For issues of high heat, high temperature Phenolic and glass-filled nylon wheels are a solution for most environs. As noted, usage is permitted beyond the given parameters, but life expectancy of the caster wheels might be greatly reduced.

Factors in Choosing An Industrial Caster Wheel

It might seem to be a simple task, choosing the appropriate wheel for a caster to be used in an industrial setting. In reality, though, the choice has many factors that should be considered for a lasting positive experience. Environment, workload, and capacity are just a few of the many considerations involved.

Industrial caster wheels need to be fitted not only to the device, but to the surroundings. Will the caster be exposed to weather, or extreme temperatures, such as an oven? Are there chemicals, oils, or other liquids that could be potentially harmful to certain wheel substances?  Is the surface with which the wheel will be in contact with smooth, rough, cracked, or have debris?

Of course, a caster wheel that can handle expected workloads and handling is a necessity. Is there chance of rough handling, or stress in a manner other than straight rolling? Perhaps the wheels are going to be static for long periods of time and only receive occasional use.  Not to be ignored is the power behind the wheeled device. Is that power to be supplied manually or by powered equipment?

Many times, the choice for wheels is made by weight capacity alone. However, consideration must be given to ergonomics. Will the wheel  begin to roll easily when engaged by a worker? Is the caster wheel going to give the least resistance when turning?

When choosing a caster wheel for industry, gather as many details as possible.  This data will be of great assistance when ordering casters. Service Caster sales reps are knowledgeable in all facets of wheel behavior, and will recommend the proper wheel for industrial usage.  Ready to order? Call us at 800-215-8220.

Choosing Pneumatic Wheels For Casters

Pneumatic wheels have two major benefits over many other caster wheels. In addition, they come in a variety of sizes, styles, and tread patterns. Read on to find out if a pneumatic wheeled caster would be useful for your application!

The first major benefit of pneumatic caster wheels is that they offer a very cushioned ride. This is useful for applications that need protection from excess vibration, or travel over rough surfaces such as rocks, concrete, dirt, or grass.

The second major benefit is that pneumatic wheeled casters provide an extremely quiet ride even on uneven and rough surfaces.  This is helpful in any environment where noise is an issue.

A variety of options are available for pneumatic wheels. Choose selections for tube and tubeless depending on application. Multiple bearing types as well as bearing sizes allow for pneumatic wheels to be used on many caster frames. Tread styles also vary greatly, and include smooth, ribbed, diamond, sawtooth, and knobby tread patterns.

Call Service Caster at 1-800-215-8220 to find out if Pneumatic Wheel Casters are appropriate for your application.

What Are Kingpinless Casters?

Kingpinless casters, as the name suggests, are casters that lack a kingpin. Is this a good thing or a bad thing? What is the purpose of the kingpin, and why would you remove it? Read on to find out.

The kingpin is a feature found in most light to heavy duty swivel casters, though it is generally not used in ultra-light duty casters such as chair casters. It is essentially a rivet, and its job is to hold the top plate and the fork of the caster together, allowing for a ball bearing housing between the two units that in turn allows the caster to swivel properly. The kingpin also tends to be a weak point in situations that put heavy stress on the caster, such as shock loading. In these cases, the kingpin can bend or even break, allowing the ball bearings to fall out and causing caster failure.

The answer to this caster failure is the kingpinless caster. Kingpinless casters are precisely engineered and machined to allow swiveling without a kingpin. The lack of the kingpin removes the casters’ typical weakest link, and provides a casters that can handle shock loading and heavy stress without failure.

Most kingpinless casters are only available at the heavy and extra heavy duty levels of casters, since the easier-to-produce a king pinned casters  can handle light and medium duty jobs with ease.

Need help choosing a kingpinless caster?  Give us a call at 800-215-8220 today.

How to Choose a Replacement Chair Caster

Did you know you’re not stuck with the cheap plastic casters that come with every office chair ever made? There are many options for replacing the casters, and, below we’re going to give a quick rundown on what information you’ll need to make an informed decision.

The first thing you will need to know is the stem size of your current casters. To find this out, you will have to remove the stem from the chair. From there, check out of our How to Measure Caster Stems page for more information. This is a very important step as casters may have several styles of stem as well as use either imperial or metric standards.

After that, determine the primary location of use. Will it be on a low pile carpet? Plastic or glass chair mat? Hardwood or tile floor? This information is critical for determining the right wheel material. On carpet, nylon or metal wheels are acceptable. On hard surfaces, especially damaging surfaces like hardwood, you want to get a soft wheel like neoprene, thermoplastic elastomer (synthetic rubber), or urethane. Soft rubber is also an option, but it may leave unsightly black marks on flooring where other soft treads will not.

From this point on, the choices are primarily aesthetic. Hooded or unhooded? If hooded, perhaps a color other than black, such as the windsor antique or bright brass? These choices won’t affect the functionality, but may be far more pleasing to the eye than the original casters.

Take a look at our online selection of casters online or give us a call at 1-800-215-8220 to speak with a sales person about all the available options.

Durometer Measurements Explained

While looking at caster wheels, you may come across the term “Durometer” and an associated number and letter. What do they mean?

Well, here’s the skinny: Durometer is both a measurement and a tool for measuring.

“But what exactly is a durometer measuring?” You wonder.

Well, it measures the hardness of an item.

There are many durometer scales represented by a letter (in the caster and wheel industry we use Shore A and Shore D) ranging in numerical value from 0-100. The higher the number, the harder the item is. For instance, a rubber band has a durometer of 25 A. Skateboard wheels (or many of the polyurethane wheels we sell) might be between 85-95 A. This doesn’t mean that they are extremely hard, just that they are one of the hardest materials the Shore A scale can measure.

The durometer of a wheel can help the user figure out how the wheel will react to its environment and the floor it is on.

What happens when an item is harder than the Shore A Scale can measure? We move on to the Shore D scale. Any of our harder wheels, such as a phenolic resin wheel, will be measured on the D scale. A phenolic resin wheel has a durometer of 90 D. Another example of an item on the D scale would be a hard hat, which has a durometer of around 75 D.

Still have questions? Give us a call at 1-800-215-8220.