Many of our customers face a common challenge: PU and PVC wheels look remarkably similar, and it’s not always easy to tell them apart. This guide provides three reliable methods you can use to identify which material you’re working with.

Why Correct Identification Matters?

Using the right material for your application is crucial for optimal performance and longevity. PU and PVC have different properties that make them suitable for specific environments and load requirements:

• PU (Polyurethane) offers superior durability, higher load capacity, and better floor protection
• PVC (Polyvinyl Chloride) provides excellent chemical resistance and lower initial cost

Misidentifying these materials can lead to premature wheel failure, unexpected maintenance costs, and potential operational disruptions. Let’s look at how you can accurately tell them apart.

Method 1: Visual Inspection

Start with a careful visual examination. Look for these distinguishing characteristics:

PU Wheels:

• Have a glossier, sometimes slightly translucent appearance
• Typically available in more vibrant colors (those bright oranges, reds, and blues are often PU)
• Show a uniform, dense interior structure if cut or damaged
• Tend to develop slight yellowing after extended UV exposure
• Display a more defined edge at the tread/core boundary
• Generally have a higher quality finish, especially in premium models

PVC Wheels:

• Feature a more matte or semi-gloss finish
• Usually come in more conservative colors (grays, blacks, and muted tones)
• Reveal a more grainy internal structure when damaged
• Maintain color better under UV exposure but may become brittle
• Often have a less distinct boundary between tread and core
• Surface typically appears slightly less refined than premium PU

Visual inspection can give you initial clues, but isn’t always conclusive on its own, especially with high-quality materials or new wheels that haven’t been subject to wear.

Method 2: The Definitive Burning Test

When you absolutely need to know with certainty, this test provides conclusive results—but should only be performed with proper safety precautions:

Sample Preparation

• Remove a small piece (about the size of a grain of rice) from an inconspicuous area
• Use metal pliers or tweezers to hold the sample—not your fingers

Testing Procedure

• Find a well-ventilated area (outdoors is best)
• Hold the sample to a flame using the pliers
• Watch the burning characteristics carefully

PU Identification Markers

• Burns with a bright yellow-orange flame
• Produces black smoke
• Gives off a surprisingly sweet, almost vanilla-like odor
• May drip when burning
• Self-extinguishes when removed from flame
• Leaves a soft, charred residue

PVC Identification Markers

• Burns with a yellow flame with distinctive green edges (this green color is your definitive clue)
• Produces thick, black smoke
• Emits a sharp, acidic chlorine smell
• Self-extinguishes when removed from flame
• Leaves a harder, brittle ash

Important Safety Note: The burning test should only be done in properly ventilated areas. The smoke from burning PVC contains hydrogen chloride gas, which is hazardous to inhale. Consider this test a last resort when other identification methods aren’t conclusive.

Common Misidentification Scenarios

Case 1: Aged Wheels

Over time, both materials can change in appearance and properties:

• PU often yellows but maintains structural integrity
• PVC may retain color better but become more brittle
  The physical tests become more important for aged wheels.

Case 2: Hybrid or Specialized Formulations

Some manufacturers produce proprietary blends or specialized formulations that combine characteristics of both materials. In these cases, the burning test may be the only definitive method of identification.

Conclusion

For most situations, the visual inspection and physical tests will give you enough information to identify your wheel material confidently while keeping your wheels intact. The burning test should be reserved only for cases where absolute certainty is required.

Understanding what material your caster wheels are made from is the first step in ensuring you’re using the right wheel for your specific application. If you’re still uncertain after performing these tests, our technical team at Wheelsway is always available to help with identification and selection of the optimal caster wheels for your requirements.

For more information about selecting the right caster wheels for your application, read our comprehensive guide on PU vs PVC Caster Wheels: The Ultimate Guide for Industry Professionals.