What are the differences in maintenance methods for nylon and polyurethane trolley wheels?

Differences in Maintenance Methods for Nylon and Polyurethane Wheels

The core difference in maintenance methods for these two wheel materials stems from their characteristics (nylon is hard and brittle, resistant to temperature fluctuations, and susceptible to oil and dirt; polyurethane is soft and flexible, has a narrow temperature range, and is susceptible to chemical corrosion). Targeted maintenance strategies are required. The specific differences are as follows:

1. Daily Cleaning: Different Cleaning Agents and Tools

Nylon wheels:

They are resistant to general stains, but it's important to prevent oil and dirt from sticking to the wheel surface (long-term oil and dirt will penetrate the wheel surface and reduce wear resistance). For cleaning, use a neutral detergent (such as dishwashing liquid mixed with water) and slightly harder tools like a brush or a stiff cloth to remove food residue, pebbles, and other foreign matter from the crevices of the wheel surface (nylon's high hardness makes it less susceptible to scratches). If oil and dirt are present, soak them in warm water and wipe them repeatedly to remove any residue.

Polyurethane wheels:

The soft and flexible material easily attracts dust but is sensitive to chemical corrosion (solvent-based cleaners, alcohol, and strong acid and alkali solutions can cause the wheel surface to swell and crack). Clean with clean water or a mild neutral detergent (pH 6-8) and gently wipe with a soft cloth or sponge. Avoid using hard tools such as brushes and steel wool (they can scratch the wheel surface and damage the elastic structure). If foreign objects are embedded in the wheel surface (such as hair or thin wire), carefully remove them with tweezers to avoid pulling and damaging the wheel surface.

2. Wear and Condition Inspection: Focus on Different Dimensions

Nylon Wheel Body:
The key areas to inspect are **"cracks" and "uniform wear." Nylon becomes brittle at low temperatures, so check the wheel surface for radial cracks (especially in winter or after exposure to low temperatures, such as near supermarket cold storage) and for chipping of the wheel rim due to impact. Also, observe whether the wheel surface is evenly worn. If there is severe localized wear (such as thinning on one side), it may be due to axle misalignment. Adjust the axle position to prevent further uneven wear.

Polyurethane Wheel Body:
The key areas to inspect are **"deformation" and "bulging." Polyurethane is highly elastic but prone to aging and deformation. Check the wheel tread for dents and bulges (which can occur with prolonged load bearing or high-temperature environments), as well as any uneven wheel surfaces due to wear (such as flattened areas or warped edges). If the wheel is slightly deformed, immediately reduce the load to prevent further deformation. Severe deformation requires immediate replacement (deformation can cause lag and unusual noises).

3. Environmental Protection: Avoiding Risks in Different Scenarios

Nylon wheels:
Prevent damage from low temperatures. Avoid leaving trolleys in environments below 0°C (such as outdoors in supermarkets or in cold storage aisles) for extended periods. If used outdoors for short periods in winter, move them indoors (above 10°C) immediately after use to prevent cracking and embrittlement of the wheel tread. Additionally, avoid prolonged contact with strong alkaline solutions (such as strong alkaline floor cleaners used in supermarkets) to prevent accelerated aging.

Polyurethane wheels:
Prevent damage from high temperatures and UV rays. Do not place the cart near heat sources (such as supermarket ovens, heaters, and high-temperature shelves) to prevent the wheel tread from softening (temperatures above 50°C can soften easily, reducing its load-bearing capacity). Also, avoid prolonged direct sunlight (such as near glass doors at supermarket entrances). Ultraviolet rays can cause polyurethane to age, harden, and lose its elasticity. Regularly apply a small amount of silicone-based lubricant (non-petroleum-based to prevent corrosion) to the wheel tread to slow down aging.

4. Abnormal Noise and Troubleshooting: Different Solutions

Nylon Wheel Abnormal Noise:
This is usually caused by a lack of lubrication in the axle or a foreign object stuck. If a hard, grinding noise is heard while pushing, first check the axle for lack of lubrication (nylon axles require lithium-based grease for wear resistance) and relubricate. If a clacking sound is heard, check for hard foreign objects (such as small stones or metal fragments) stuck in the wheel tread. Remove them with tools and clean the wheel tread (nylon is hard, so foreign objects are less likely to become embedded too deeply).

Polyurethane Wheel Abnormal Noise:
This is usually caused by wheel deformation or foreign objects embedded in the soft surface. If a "friction and vibration" sound is heard, uneven wheel wear may be causing eccentricity. Check the wheel for deformation and replace it if necessary. If a "sizzling" sound is heard, hair or thin wire may be wrapped around the axle or embedded in the wheel tread. Clean the axle with a soft cloth and remove the embedded object with tweezers. Avoid pulling hard (to avoid tearing the wheel tread).

5. Determining the Replacement Period: Based on Different Wheel Types
Nylon wheels:
They have a longer lifespan (usually 1.5-2 years). Replacement is determined by **"tread thickness" and "cracks": When the wheel tread wears to less than 1/3 of its original thickness, or radial cracks exceeding 2 cm appear (which cannot be repaired), replacement is required. If the wheel is only slightly chipped, polish the rim to a smooth finish and continue use. Polyurethane wheels:
The lifespan is relatively short (typically 1-1.5 years). Replacement is based on **"degree of deformation" and "loss of elasticity."** Even if the wheel tread thickness does not meet the standard, if there are noticeable bulges or dents (impairing smooth propulsion), or if the wheel tread becomes hard and loses its springiness when pressed (due to aging), it must be replaced immediately. If the wheel is only slightly worn, it can be cleaned and continued to be used, but the inspection interval should be shortened.