What are the shortcomings of rubber casters?

The shortcomings of rubber casters are highly related to their material properties, particularly in wear resistance, weather resistance, and load-bearing capacity. These shortcomings directly limit their applicability (e.g., long-term use outdoors or in high-wear environments). These shortcomings can be categorized into the following five main categories:

1. Poor wear resistance and short service life (core shortcoming)
Rubber (especially natural rubber and common synthetic rubber) has a low surface hardness (Shore A50-70), far lower than common industrial caster materials such as nylon (Shore D70-80) and polyurethane (Shore A85-95), resulting in extremely poor wear resistance:

Susceptible to wear from rough surfaces: On surfaces that are not perfectly smooth, such as concrete and tile, fine sand, gravel, and metal debris can directly scratch the rubber wheel surface. Within a short period of time (1-3 months of frequent use), the wheel surface will dent, wear away grain, and even create "flat areas."

High replacement frequency: Under the same intensity of use, the service life of rubber casters is only one-third that of polyurethane casters, and reinforced nylon casters are only one-third that of polyurethane casters. 1/5. If used in frequently moving equipment (such as workshop turnover vehicles), frequent replacement is required, increasing maintenance costs and downtime.

2. Poor weather resistance and prone to aging and deterioration (a fatal flaw for outdoor applications).
Rubber's molecular structure is extremely sensitive to UV rays, temperature fluctuations, and humidity. Long-term exposure to non-indoor environments causes rapid aging, which is the core reason it cannot be used outdoors:

Susceptible to cracking and hardening due to UV exposure: UV rays in outdoor sunlight damage the rubber's molecular chains, causing the wheel tread to become brittle in 1-2 months, and visible cracks in 3-6 months (especially for natural rubber). In severe cases, the wheel body can break, losing its support capacity.

Temperature and humidity fluctuations accelerate damage: At low temperatures (≤0°C), rubber loses its elasticity, becomes hard and brittle, and can break with even the slightest impact. High temperatures (≥35°C) and high humidity can cause rubber to mold and delaminate (separation between the wheel tread and the core). Rain and dew can also cause hydrolysis of the rubber, further shortening its lifespan.

3. Weak load-bearing capacity, unsuitable for heavy equipment.
Rubber has limited physical strength (tensile and compressive strength), making it unable to withstand heavy loads and prone to permanent deformation when bearing weight.
Low upper limit for single wheel loads: Ordinary rubber casters typically have a single wheel load capacity of 300kg or less, far lower than nylon casters (500-2000kg) and cast iron casters (≥1000kg). If forcibly overloaded, the wheel surface will be compressed into a flattened shape and unable to return to its original shape, causing equipment to lag and uneven load distribution.
Poor impact resistance: The rubber wheel surface is easily squeezed and deformed by bumps or minor impacts, and may even cause the wheel core to shift, making it difficult to ensure stable movement of equipment. Therefore, it is not suitable for applications with high load requirements, such as heavy tool carts and mold transfer carts.

4. Easy to pick up impurities, making cleaning and maintenance difficult.
Rubber casters have a certain degree of stickiness (especially at high temperatures), which easily attracts dust, debris, hair, and other impurities from the floor. This creates two major problems:
Increased resistance to movement: Adherent impurities increase friction between the wheel surface and the floor, making previously easy-to-move equipment feel heavy and even "stuck" (impurities become trapped between the axle and the wheel body);
Frequent cleaning required: If used in environments with high cleanliness requirements (such as food processing facilities and electronics workshops), adherent impurities may fall off and contaminate products, requiring regular wiping of the wheel surface with a damp cloth, resulting in high maintenance costs. Nylon and polyurethane casters, on the other hand, have smooth surfaces that resist pick-up, reducing cleaning frequency by over 50%.

5. Limited Chemical Resistance and Susceptibility to Corrosion
Ordinary rubber has poor tolerance to oil, solvents, and acids and alkalis, and its performance deteriorates easily after contact:
Swelling and Softening in Contact with Oil: If used in oily environments such as machine shops and auto repair shops, the rubber wheel tread will absorb the oil, causing the wheel to swell, lose elasticity, and even experience "swelling cracking," shortening its service life to less than one month.
Acid and Alkali Attack: In environments with acidic and alkaline reagents, such as laboratories and electroplating workshops, rubber will be corroded by chemicals, resulting in surface spots and damage, making it unusable. (Only specially modified rubbers, such as nitrile rubber and chloroprene rubber, can withstand mild oil/acid/alkali conditions, but these are more expensive.)

In summary: The shortcomings of rubber casters determine their application limitations.

The shortcomings of rubber casters (poor wear resistance, poor weather resistance, weak load-bearing capacity, and easy staining) make them suitable only for narrow applications: indoor, low-frequency movement, light loads, chemical-free operation, and high demands for shock absorption, quiet operation, and floor protection. (For example, office carts, hospital ward transfer vehicles, and temporary turnover of precision instruments). They are completely unsuitable for outdoor applications, high wear and tear, high load-bearing capacity, and chemically contaminated industrial applications. When selecting a caster, prioritize whether the application matches its shortcomings to avoid frequent damage caused by mismatched materials.