Which scenarios are not suitable for polyurethane casters?

Although polyurethane casters are widely used, due to their material properties (limited high-temperature resistance, poor corrosion resistance, etc.) and performance limitations, they are prone to damage, failure, or safety hazards in the following scenarios. Casters made of other materials (such as metal, special rubber, nylon, etc.) should be preferred:

1. Long-term High-temperature Operation
When ambient temperatures consistently exceed 120°C, polyurethane will gradually soften, become sticky, or even melt, completely losing its load-bearing and rolling capacity. Therefore, they are not suitable for:
Industrial Applications: Molten Steel Transfer Areas in Metallurgical Plants, High-Temperature Forming Lines in Glass Factories, and Fixed Handling Stations around Ovens/Kilns;
Special Applications: Extremely High-Temperature Environments such as High-Temperature Sterilization Workshops (such as dry heat sterilization areas with temperatures exceeding 150°C), and volcanic geological surveys.
For these scenarios, cast iron casters, high-temperature-resistant ceramic casters, or special alloy casters that can withstand temperatures exceeding 200°C are recommended.

2. Long-term contact with highly corrosive media
Polyurethane cannot withstand long-term corrosion from strong solvents, concentrated acids, and concentrated alkalis. Continuous contact with highly corrosive substances can easily cause the tread to swell, decompose, and crack. These are not suitable for:
Chemical industry: Material handling vehicles in acid and alkali storage areas (such as those transporting concentrated hydrochloric acid and sodium hydroxide solutions), and organic solvent production workshops (such as those storing acetone, toluene, and xylene).
Laboratory: Carts frequently handling highly corrosive reagents (such as nitric acid and sulfuric acid), or mobile equipment used for chemical waste treatment.
For these applications, use perfluoroelastomer casters, polytetrafluoroethylene (PTFE) casters, or metal casters with an anti-corrosion coating.

3. Extremely Cold Environments
When the ambient temperature remains below -30°C for an extended period, the mobility of polyurethane molecules decreases significantly, causing the tread to become hard and brittle, completely losing its elasticity. This leads to a dramatic increase in pushing resistance and a tendency to crack due to impact. These applications are unsuitable for:
Outdoor applications: Outdoor logistics handling during northern winters (temperatures below -35°C), and for moving parts of polar research equipment;
Warehousing applications: Deep-freeze cold storage below -40°C (such as those storing liquid nitrogen-frozen food and biological samples), or material transfer in cryogenic laboratories.
For these applications, we recommend using cold-resistant rubber casters (such as neoprene), nylon casters, or special plastic casters with added cold-resistant additives.

4. Ultra-High-Frequency, Ultra-Lightweight Applications

Polyurethane casters, due to their thick tread and often paired with steel hubs, weigh 30%-50% more than plastic casters of the same specification. This can increase labor burden in applications with strict weight restrictions and high movement frequency. They are not suitable for:

Portable Equipment: Portable medical carts (such as emergency carts and mobile monitors) that require frequent manual handling, and small household folding carts.

Lightweight Applications: Lightweight material transfer in the aerospace industry (where weight accuracy is critical) and fast-moving stage prop carts (where a single person must easily push them).

For these applications, lightweight casters such as nylon casters and polypropylene (PP) casters, or weight-reducing casters with a hollow hub design, should be selected.

5. Long-term Use on High-Abrasion, Rough Surfaces
Although polyurethane offers superior wear resistance to ordinary rubber, long-term use on extremely rough, high-friction surfaces (such as unhardened gravel or areas with accumulated steel slag) can cause the tread to rapidly wear due to constant friction, significantly shortening its service life. These casters are not suitable for:
Outdoor projects: gravel transport trucks on construction sites and ore transfer carts in mining areas;
Special surfaces: scattered steel shavings in machinery plants and rough concrete surfaces (with sharp objects) at waste disposal sites.
For these applications, we recommend using cast iron casters, all-steel casters, or special wear-resistant rubber casters with a steel wire reinforcement layer on the tread.

6. Applications requiring frequent, high-intensity impacts
Although polyurethane offers some shock absorption, its impact resistance is weaker than that of metals and specialty elastomers. Frequent, high-intensity impacts (such as frequent climbing and descending high steps, or repeated impacts of heavy objects against the casters) can easily lead to tread cracking and wheel hub deformation. Therefore, it is not suitable for:

Loading and unloading applications: In warehouses without ramps, where carts need to be frequently moved on and off loading and unloading platforms (height difference > 10cm);

Heavy equipment: Mobile support casters for heavy machinery (such as small machine tools) (moving equipment is prone to impacts caused by uneven surfaces).

For these applications, steel casters, shock-absorbing casters with buffer springs, or impact-resistant casters with treads made of highly elastomer materials should be used.