Definition: Chemical resistance is a caster’s ability to withstand exposure to chemicals without degradation of wheels, bearings, seals, or frames.
Includes: Resistance to corrosion, swelling, softening, cracking, and lubricant breakdown.
Why chemical resistance matters
Chemical exposure can destroy casters long before load limits are reached.
- Causes wheel swelling or softening
- Strips bearing lubrication
- Accelerates corrosion of frames and fasteners
- Leads to sudden, unpredictable failures
Reality: Many “mysterious” caster failures are chemical compatibility issues.
Material compatibility overview
| Material | Chemical resistance | Notes |
|---|---|---|
| Rubber | Poor–moderate | Swells with oils and solvents |
| TPR | Moderate | Better than rubber, still limited |
| Polyurethane | Good | Formulation dependent |
| Nylon | Excellent | Resists most chemicals |
| Phenolic | Excellent | Strong against oils and solvents |
| Stainless steel | Excellent | Best for corrosive environments |
Design and bearing considerations
- Sealed bearings prevent chemical ingress
- Grease must be chemically compatible
- Stainless frames resist corrosion better than plated steel
- Open raceways allow drainage but expose internals
Rule: Chemical resistance is determined by the weakest exposed component.
Common engineering mistakes
- Assuming all polyurethanes resist chemicals equally
- Ignoring cleaning chemicals and sanitizers
- Using zinc-plated steel in corrosive environments
- Overlooking lubricant compatibility
Rule: Always specify the exact chemicals and exposure conditions.
FAQs
Are chemical resistance charts universal?
No. They vary by formulation and manufacturer.
Do cleaning chemicals count?
Yes. Cleaners and sanitizers are common causes of failure.
Is stainless always required?
Not always, but it is safest for corrosive exposure.
Can sealed bearings fully prevent chemical damage?
They reduce risk but are not immune to prolonged exposure.