What are the general requirements for casters used on cleaning carts?

Cleaning carts (such as property management vehicles, shopping mall cleaning carts, and hotel linen carts) are used in environments characterized by complex surfaces (dusty, water-stained, and littered), high-frequency movement (multiple round trips daily), diverse loads (cleaning agents, wastewater, tools, linens, etc.), and changing environments (both indoors and outdoors). Therefore, their casters must be designed around three core requirements: durability, adaptability, and stain resistance. Specifically, they must meet the following requirements:

1. Core Performance: Strong load-bearing capacity + durability to handle complex loads and floor conditions.

The load requirements of cleaning carts vary greatly depending on their use (e.g., a small tool cart can support 50kg, while a large linen cart/garbage cart can support over 200kg). Furthermore, these carts often operate in rough or debris-laden environments. Therefore, casters must first meet "basic durability":

High load-bearing capacity and structural strength.

The load capacity must be determined based on the type of cleaning cart:

Lightweight cleaning carts (such as handheld tool carts and small dust carts): Each caster must support a load of 20kg or more, with a 20% margin for the total load capacity (to avoid excessive loads caused by cleaning agents/garbage carts). Stacking tools together can lead to local overloading.

Medium-sized cleaning vehicles (such as shopping mall garbage trucks and hotel linen carts): A single caster must have a load capacity of 50 kg or more. A "double wheel set" (two wheels in a single mounting position) is preferred (this distributes the pressure and prevents axle bending).

Heavy-duty cleaning vehicles (such as industrial workshop sweepers and large sewage recycling trucks): A single caster must have a load capacity of 100 kg or more. The wheel frame must be made of thickened stainless steel (≥3 mm thick) or cast steel, and the axle must be equipped with heavy-duty needle roller bearings (impact and crush-resistant).

Impact-resistant structure: Cleaning vehicles often roll over thresholds, tile joints, and even small stones. Therefore, the wheels must be resistant to cracking (such as nylon wheels or high-hardness PU wheels), and the wheel frame welds must be secure (no risk of weld defects or cracking). Superior wear and impact resistance
Preferred wheel materials include modified nylon wheels (PA66 + glass fiber reinforcement) or high-hardness polyurethane wheels (PU hardness ≥ 90 Shore A):
Modified nylon wheels: Their wear resistance is 1.5 times that of ordinary nylon wheels, allowing them to withstand long-term friction on rough surfaces like concrete and asphalt. They are also heat-resistant (-40°C to 120°C, suitable for outdoor exposure in winter and summer).
High-hardness PU wheels: They offer both wear resistance and shock absorption, preventing them from getting stuck when rolling over small debris (such as paper scraps and sand), and are quieter than nylon wheels (suitable for noise-sensitive indoor environments like shopping malls and hotels).
Avoid ordinary rubber wheels (which are easily corroded by cleaning agents and scratched by sharp objects) and cast iron wheels (which are heavy and prone to rust, suitable only for extremely heavy-duty industrial applications).

2. Environmental Adaptability: Anti-fouling, Anti-rust, and Anti-corrosion to meet the unique characteristics of cleaning environments.
Cleaning carts are frequently exposed to cleaning agents (acidic and alkaline), water stains, and debris. Therefore, casters must be dirt-resistant, corrosion-resistant, and easy to clean.
Corrosion-resistant: Resistant to cleaning agents and water stains.
The wheel frame must be made of 304 stainless steel (ordinary galvanized frames rust after 1-2 years, while 304 stainless steel can withstand neutral detergents and small amounts of acidic detergents, such as white vinegar descaling agents).
The wheel body must be chemically resistant: Avoid ordinary plastic wheels (which swell easily with strong alkaline detergents). Choose nylon wheels (resistant to most acids and alkalis) or PU wheels (resistant to neutral and weak acids and alkalis, but avoid long-term contact with highly corrosive detergents such as oxalic acid).
Bearings must be sealed to prevent dust and hair from being caught in motion. Double-sided sealed bearings (such as sealed ball bearings) are recommended to prevent dust from entering, causing seizures and wear, thereby extending bearing life. Anti-fouling and easy to clean: No dead corners, no dirt traps.

Choose a one-piece solid wheel or a honeycomb wheel. Avoid hollow wheels or spoke wheels (garbage and hair can easily get stuck in the gaps, requiring disassembly and labor for cleaning).

The wheel edge should be smooth and burr-free to prevent it from catching on garbage bags or rags. It can be easily rinsed clean with a damp cloth or a high-pressure water gun; no additional scrubbing is required.

3. Practical Functionality: Flexible, Stable, and Safe, Suitable for Frequent Mobility Needs
Cleaning carts require frequent daily movement (e.g., property management staff pushing carts up and down stairs or through shopping malls). The flexibility and stability of the casters directly impact work efficiency:
Steering and Mobility: Flexible and Stable
Preferably choose a combination of "4 universal wheels" or "2 universal wheels + 2 fixed wheels":

4 universal wheels: Suitable for situations requiring 360° steering (e.g., narrow shopping aisles, elevator adjustments), especially models with a "locking universal wheel function" (locks the universal wheels when pushing in a straight line, preventing deviation and saving effort and efficiency);
2 universal wheels + 2 fixed wheels: Suitable for long-distance straight-line movement (e.g., cleaning residential hallways). The fixed wheels enhance stability and prevent the cart from spinning when pushing uphill. Universal wheels should have minimal steering resistance: no noticeable jerk during rotation and be easily pushed with one hand (especially for female cleaners, who should reduce manual effort). The steering shaft should be well lubricated (pre-installed with long-lasting grease to avoid frequent maintenance).

Braking and stability: Safe and non-slip.

A dual brake system is required (locks both the wheel's rolling motion and the steering shaft's rotation), not a single brake (locks only the wheel, but the steering shaft may still shift).

Cleaning trucks are often parked on slopes (such as in hallways or near shopping mall escalators) or slippery surfaces (such as bathroom entrances). Dual brakes secure the vehicle and prevent it from sliding, potentially spilling cleaning agents or dropping trash.

The brake pedal should be wide and non-slip (easy to apply even with gloves). There should be a noticeable "click" after braking, with no looseness or rebound (if the rear caster still rolls slightly after being pressed, it should be replaced immediately). Obstacle Crossing and Height: Adapt to Scenario Requirements
Select a wheel diameter of 4-6 inches. A wheel diameter too small (≤3 inches) can easily get stuck on thresholds and tile joints (cleaning carts often cross elevator thresholds, which are about 2-3 cm high). A wheel diameter of 4-6 inches allows for easy crossing and reduces rolling effort (the larger the diameter, the less rolling resistance).
The caster mounting height must be adapted to the vehicle's base: Ensure the base of the vehicle is at least 8 cm above the ground (to facilitate dust removal and accommodate a robot vacuum). However, it should not be too high (to avoid shifting the center of gravity upward and causing tipping when loaded).

4. Summary: The "Golden Standard" for Cleaning Cart Caster Selection
Core Logic: Sufficient load-bearing, wear-resistant and durable (for complex surfaces) → Rust-resistant and corrosion-resistant (for cleaning agents and water stains) → Flexible dual brakes (for frequent movement) → Easy to clean (reduced maintenance time).
Recommended combinations:
Light-duty cleaning carts: Modified nylon/PU wheels + 304 stainless steel frame + 4 swivel casters (with dual brakes) + 4-5 inch diameter;
Medium-duty cleaning carts: Dual wheel set (modified nylon wheels) + thickened 304 stainless steel frame + 2 swivel casters + 2 fixed casters (with dual brakes) + 5-6 inch diameter.
Casters selected according to these criteria are suitable for frequent use and complex environments of cleaning carts, reducing the frequency of replacement and the intensity of cleaning work.