Caster Wheel Materials for Industrial Dollies: Rubber, Polyurethane, and Nylon

Rubber, polyurethane, and nylon caster wheels differ in hardness, resilience, rolling resistance, and floor interaction, but the material names alone do not set a universal ranking. Soft rubber compounds can cushion a load, and hard nylon deforms little on smooth floors. Polyurethane spans a wide hardness range, so the wheel’s specification, floor, load, and environment decide the comparison.

Comparisons here rely largely on one caster seller’s published guidance, named below. Check any selection against the data sheet for the specific wheel.

What Determines Caster Wheel Behavior?

Material is one of seven variables.

• Wheel material: sets compliance, wear, and chemical behavior
• Diameter: a larger wheel rolls over obstacles more easily
• Load: what each wheel actually carries
• Floor: its hardness, smoothness, and debris
• Speed: push speed or tow speed
• Bearing: its type affects swivel and rolling friction
• Duty cycle: occasional moves or continuous operation

CasterHQ, an industrial caster seller, describes rolling behavior in its rolling resistance guide as a system property: same wheel, different floor, different coefficient. A material ranking without a floor attached is therefore incomplete.

Rubber Caster Wheels

Rubber deforms at the contact patch. Compliance is its main benefit, and it is the source of its main drawback. The tread conforms to small irregularities, passes less vibration to the load, and grips well when starting and stopping.

The same softness absorbs energy as it rolls. CasterHQ warns against specifying soft rubber for “ergonomic feel” on cart casters, since it has higher rolling resistance than industrial polyurethane, and push force can rise rather than fall. Its materials matrix also lists solid rubber at 200 to 500 lb per typical 5 in wheel, the lowest of the materials listed.

That load band describes typical products from one seller. It is not a rating for any wheel you might buy.

Polyurethane Caster Wheels

Polyurethane is a family rather than one material, with formulations that vary between suppliers. CasterHQ lists durometer options from 75A, which it calls soft and shock absorbing, to 95A or more, which it calls hard and low rolling. For its 95A wheels, it cites a coefficient of 0.03 on average, from its own customer data.

The seller’s matrix rates polyurethane’s floor protection as excellent and gives it a temperature band of −20°F to 180°F. Two wheels both labeled polyurethane can behave very differently, so request the durometer and tread specification. One seller’s listings show how wide the label runs at the same 5 in diameter: a Colson 5 in by 1-1/4 in tread wheel at 300 lb with a 45 Shore D tread, and a Duralast 5 in by 2 in wheel at 1,360 lb with a 70 Shore D tread. Tread width, hardness, and construction all differ, so this shows a range rather than the effect of any one factor. A wheel-only rating also cannot be compared directly with the rating of a complete swivel caster. Confirm any rating with the manufacturer’s current data.

Nylon Caster Wheels

Nylon is hard, and that shapes its behavior. Little deformation at the contact means low rolling resistance on a smooth surface, and CasterHQ’s matrix lists glass-filled nylon at 800 to 2,500 lb per typical 5 in wheel.

The floor pays for that. A hard wheel sends more stress into the slab, and CasterHQ rates nylon’s floor protection as poor. It also transmits cracks and joints to the load and into the room. Nylon has its own chemical resistance profile too, which is worth checking against the chemicals in use.

Debris matters more with hard treads, since a small stone can stop a hard wheel in a way that a softer tread might roll over or absorb.

How Wheel Hardness Is Described

Shore hardness comes in scales. Shore A covers softer elastomers such as rubber and softer urethanes. Shore D covers harder materials such as hard urethanes and plastics. Blickle, a wheel and caster manufacturer, lists standard solid rubber at 80 Shore A, polyurethane grades at 75 and 92 Shore A, and nylon at 70 Shore D in its wheel-series guide, and it describes those values as reference figures. A polyurethane wheel can therefore be softer than a rubber one.

The scales should not be casually interchanged. ASTM D2240, listed as D2240-15(2021), says indentor geometry and applied force influence the measurements such that no simple relationship exists between readings from one type of durometer and another. A wheel at 95 Shore A and one at 95 Shore D are very different, because the numbers belong to different instruments. A number without its scale letter is not a specification. Ask for both, and note that hardness alone does not define rolling behavior, since a compound’s resilience also matters.

Rolling Resistance and Startup Force

Starting a dolly and keeping it rolling are two separate forces.

• Force required to start movement: CasterHQ says breakaway force is 1.5 to 3 times higher than steady-state rolling resistance
• Continuous rolling resistance: it gives a coefficient of 0.01 to 0.08 for industrial casters, meaning pounds of push per pound of load
• Wheel radius: larger wheels reduce the effect of floor deformation and small obstacles
• Load: more load means more force at a given coefficient
• Floor condition: a softer or rougher floor increases the coefficient

A worked example shows the range, using a hypothetical 600 lb dolly and coefficients within the seller’s stated range.

Assumed coefficient	Rolling force	Breakaway at 1.5 times	Breakaway at 3 times
0.02	12 lb	18 lb	36 lb
0.05	30 lb	45 lb	90 lb
0.08	48 lb	72 lb	144 lb

These are estimates of pushing effort based on one seller’s coefficients. Measure actual push force with a gauge on the actual floor. Ergonomic acceptability is a separate assessment.

Floor Conditions and Wheel Material

Floor	Consideration
Smooth concrete	Harder treads can roll easily here; check for marking
Uneven surfaces	Softer treads and larger diameters absorb more shock
Floor debris	Hard treads can stop on or crush small debris; soft treads can pick it up
Wet environments	Check traction and the moisture behavior of the material
Sensitive floors	Softer, non-marking treads protect better, at some cost in rolling force

CasterHQ’s advice runs in the same direction: never specify a caster on rolling resistance alone, because a wheel with ultra-low resistance can trade away floor protection, shock absorption, or capacity.

Environmental Factors

• Chemicals: oils, cleaners, and solvents attack materials differently, so check by chemical name
• Temperature: CasterHQ’s matrix gives each material a band, and a freezer or an oven room can rule out a candidate immediately
• Moisture: some materials absorb water, which can change dimensions and properties
• Cleaning methods: washdown areas expose wheels and bearings to water and chemicals

Bearing and mounting choices may fail in these environments before the tread does.

Other Industrial Wheel Materials

Three materials are compared above, but they are not the only options. Phenolic, cast iron, and steel serve high-load or high-temperature uses, with lower floor protection. CasterHQ’s matrix lists phenolic for use up to 325°F, and rates cast iron and forged steel as very low rolling but very poor in floor protection. TPR (thermoplastic rubber) is another soft option that seller groups with rubber.

How to Read a Wheel Manufacturer’s Data

• Rated load: at what speed, and on what floor? A rating has conditions
• Wheel diameter: is the rating tied to this size?
• Tread: material, hardness, and scale
• Bearing type: its rating may be lower than the wheel’s, and then it governs
• Duty conditions: continuous running, temperature, and impact allowances

Manufacturers also publish their own scoring schemes. Hamilton Caster’s wheel rating system is one to read directly if you are comparing its wheels, and scores from one maker’s scheme should not be carried over to another’s.

Estimating Load per Wheel

Assume a hypothetical dolly with 600 lb total: load plus dolly weight, on four wheels.

• Ideal average: 600 / 4 = 150 lb per wheel
• If one wheel is off the floor: 600 / 3 = 200 lb per wheel

CasterHQ tells buyers to match capacity per caster to total load divided by 3, because one caster may be airborne. Neither of these lines is a safe caster rating calculation. Uneven loading, floor irregularity, shock, and the manufacturer’s rating conditions all have to be considered.

Comparing the Three Materials

Material	Relative compliance	Floor sensitivity	Noise	Rolling behavior	Environmental considerations
Rubber	Highest	Gentle on floors	Quiet	Higher effort under load	Check oils and temperature band
Polyurethane	Varies by compound	Gentle, compound dependent	Quiet to moderate	Low to medium	Check heat limit, and moisture for the compound
Nylon	Lowest	Harder on floors, can mark	Louder on rough floors	Low on smooth floors	Check moisture and chemical data

The Next Handling Question

A dolly moves by hand on wheels. Moving a metal rack by forklift involves a different interface, and forklift entry clearance on transport racks deals with that one. Lifting a loaded crate by hand adds yet another set of limits, explained in how crate handle design affects manual handling.

Caster Material FAQ

Why can a hard caster wheel be easier to push on one floor and worse on another?

Rolling resistance depends on the wheel and floor together. On smooth, hard concrete, a hard wheel deforms little and rolls easily. On a rough or cracked floor, the same wheel has to climb every irregularity, and it may stop at debris. A softer wheel flexes over those features, so its relative performance improves there.

Does using a larger-diameter wheel always solve rolling-resistance problems?

No. A larger wheel can help with floor irregularities, and CasterHQ treats diameter as a factor that reduces push force. But it raises deck height, adds cost, and does nothing about a bearing problem or a wheel that is simply too soft for the load. Compare options at the actual floor and load.

Making the Selection

No single material wins, and the choice comes down to which limit binds first. Temperature and chemistry can remove candidates outright, so they come before any comparison of feel. A finished or sensitive floor points to softer treads, while a rough or dirty one points to softer treads or larger diameters. Load is judged on the worst-case wheel rather than the average, then confirmed against the manufacturer’s rating and bearing limits. Published coefficients can narrow the list, but only a force gauge on the real floor, reading both breakaway and rolling force, settles how hard the dolly is to push. If that effort is high, a harder compound or a bigger wheel is the next thing to try, before a choice that damages the floor.