What environmental factors should be avoided when maintaining polyurethane casters?

When maintaining polyurethane casters, it's important to avoid four environmental factors that can accelerate material aging, damage the structure, or affect performance. These factors are as follows:

1. Extreme Temperature Environments: Preventing Physical Property Loss
High Temperature Environments (>80°C)
The typical upper temperature tolerance limit for polyurethane materials is approximately 80°C. Prolonged exposure to high temperatures (such as around ovens/boilers, in exposed outdoor areas during summer, and in high-temperature drying workshops) can cause the wheel to soften, become sticky, and deform. It can even cause material degradation and emit an odor. This not only reduces load-bearing capacity but can also affect mobility due to the wheel tread sticking to the ground. Temperatures exceeding 120°C can also cause partial carbonization of the wheel, rendering it useless.

Low Temperature Environments (<-20°C)
At temperatures below -20°C, polyurethane gradually loses its elasticity, becoming stiff and brittle. Rolling resistance increases significantly, completely negating its original shock-absorbing properties. Frequent pushing or heavy loads at this temperature can cause the wheel tread to crack or even shatter from bumps. This makes the wheel particularly unsuitable for cold storage or outdoor use in northern winters, where the wheel is exposed to low temperatures.

2. Highly Corrosive Chemical Environments: Avoid Material Degradation
Avoid direct contact with strong solvents, strong acids, and strong bases. These include:

Strong solvents such as gasoline, acetone, banana oil, and thinner can dissolve the molecular structure of polyurethane, causing swelling, peeling, and stickiness on the wheel tread, ultimately leading to complete damage in a short period of time.

Strong acids/bases such as industrial hydrochloric acid, sulfuric acid, and sodium hydroxide solution (caustic soda) can chemically react with polyurethane, damaging the wheel surface structure, causing cracking, discoloration, and reduced strength. They can also corrode the caster bracket (such as a standard steel bracket), furthering overall damage. Even with weak acid and alkaline cleaners used in food/pharmaceutical applications, avoid prolonged soaking and wipe dry promptly after cleaning.

3. High-Abrasion and Sharp Impurity Environments: Prevent Physical Damage to the Wheel Surface

Rough and hard surfaces, such as unpolished concrete floors, gravel-covered floors, and workshop floors with accumulated metal debris, can subject the wheel surface to constant friction and impact, accelerating wear, fuzzing, and cracking. They can even cause sharp impurities to pierce the wheel (especially with non-solid polyurethane casters).

Frequently running over obstacles, such as raised metal strips, uncleaned screws/nails, and gaps in door sills, can cause excessive stress on the wheel surface, leading to dents and deformation, and even loosening the connection between the bearing and the wheel, affecting overall stability.

4. Humidity and Highly Polluted Environments: Avoid Structural Corrosion and Performance Degradation. Long-term humidity and water accumulation, such as in the washrooms of food processing plants or in open, rainy environments, can cause poorly sealed caster bearings to allow water to seep into the bearings, leading to rust and seizure. Humidity also accelerates the aging of polyurethane wheels (especially those that are not waterproof), reducing their service life.

High dust/oil accumulation, such as in flour mills and machinery lubrication workshops, can clog bearing gaps, causing lubrication failure and stalling. Oil adheres to the wheel surface for extended periods, penetrating the polyurethane and affecting its elasticity. Dirt accumulation can also increase rolling resistance and worsen wear.