Spare Wheels & Castors

Castor Wheels — More Than Just a Spare Part

A castor wheel does a lot of quiet work. Every time a trolley corners smoothly, a sack truck rolls straight, or a warehouse trolley glides across a floor without vibrating, the castors are doing their job perfectly.

When they're not — when a wheel starts to drag, wobble, or go flat — you notice immediately. The load feels harder to move, steering becomes imprecise, and in worst-case scenarios, a failing castor under a heavy load becomes a handling risk.

Replacing worn or damaged castor wheels promptly isn't just about convenience. It keeps your equipment performing as it should and keeps your team working safely.

Types of Castor Wheels — Which One Do You Need?

• Swivel castor wheels:  The most common type for sack trucks,  platform trucks, warehouse trolleys, and mobile equipment. A swivel castor rotates 360 degrees, giving full manoeuvrability in any direction. Swivel castor wheels are the standard choice for all four corners of a platform trolley, or the front wheels of equipment that needs to turn freely.
• Fixed castors:  Rotate in one direction only, forwards and back. These are often used in combination with swivel castors: fixed at the rear for directional control, and swivel at the front for steering. These are less common as a standalone replacement, but it is important to replace them when needed.
• Braked castors:  These are swivel castors with a foot-operated brake that locks the wheel in place. Essential for equipment that needs to stay stationary while loading — workbenches, medical trolleys, catering equipment, and any application where unexpected movement is a risk.
• Heavy duty castor wheels:  Built from thicker materials with reinforced housings and higher-rated axles. Heavy duty castor wheels handle loads that standard castors simply aren't rated for — industrial trolleys, heavy workshop equipment, and large & heavy duty trucks. If you're replacing castors on equipment that regularly moves loads of 200kg or more, heavy duty is the category you need.
• Small wheel castors:  Smaller diameter castors for lighter equipment —these are suitable for office furniture, display units or light-duty trolleys. A smaller wheel castor typically has a lower load rating but a more compact profile, suited to equipment with tight clearance.

Heavy Duty Castor Wheels — When Strength Matters

Standard castors are fine for most everyday applications. But put them under loads they weren't designed for, and they can wear quickly, deform, or fail outright.

Heavy duty castor wheels are built to a different spec:

• Thicker wheel cores: pressed steel or reinforced nylon that resists deformation under sustained load
• Higher axle ratings: the bolt or stem that attaches the castor to the frame is rated for greater shear force
• Wider wheel face: distributes the load across a greater contact area, reducing floor pressure and wear on both the castor and the surface
• Robust swivel housing: the bearing housing on a heavy duty swivel castor is designed to handle lateral forces as well as vertical load

If your current castors are wearing unevenly, cracking, or flattening at the contact point, it's often a sign they're underrated for the actual load. Upgrading to a correctly rated heavy duty castor wheel resolves this and typically extends service life considerably.

Swivel Castor Wheels — Manoeuvrability Where You Need It

A swivel castor wheel isn't just about turning — it's about how smoothly and responsively a piece of equipment handles. A good swivel castor should:

• Rotate freely through 360 degrees with no binding or resistance
• Return consistently to the direction of travel without dragging
• Maintain smooth rotation under load, not just when the equipment is empty

Worn swivel castors often show the first signs of failure as resistance or wobble in the swivel housing rather than the wheel itself. If a trolley or truck is becoming harder to steer even though the wheels look intact, the swivel bearing is often the culprit.

Replacing it with a quality swivel castor wheel restores full manoeuvrability and makes a noticeable difference to how easily the equipment handles.

Puncture Proof Tyres — Less Maintenance, More Reliability

Pneumatic (air-filled) tyres deliver a smooth, cushioned ride — but they’re prone to punctures, and a flat at the wrong moment can disrupt operations. That’s where puncture-proof options come in.

There are two main types to consider. Foam-filled tyres retain the structure and cushioning of pneumatic wheels but are filled with foam instead of air, eliminating the risk of punctures. Solid rubber tyres, on the other hand, contain no air at all — making them completely immune to flats and virtually maintenance-free.

Solid tyres handle moderate loads well and roll comfortably on smooth to semi-rough surfaces. The trade-off is slightly less cushioning than pneumatic or foam-filled options — but in most warehouse and commercial environments, that difference is minimal.

If your equipment currently runs on pneumatic wheels that frequently puncture, switching to a puncture-proof solution — whether foam-filled or solid — is a straightforward upgrade that removes a recurring maintenance headache.

How to Choose the Right Replacement Castor Wheel

Getting the right replacement is mostly about matching four things to your existing equipment:

1. Fitting type:  How the castor attaches to the frame — most commonly a bolt hole (plate fixing) or a stem (push-in or threaded). Check your existing castor before ordering.

2. Wheel diameter:  Measure the overall wheel diameter in millimetres. Changing the equipment's diameter alters the ride height, affecting stability and load balance.

3. Load rating:  Check the rated capacity per castor. If you're running four castors and the trolley is rated at 400kg, each castor needs to be rated for at least 100kg — ideally with a safety margin above that.

4. Wheel material

• Polyurethane — smooth, quiet, good for hard floors, leaves no marks
• Rubber — better grip, absorbs vibration, suits indoor and outdoor use
• Nylon — hard-wearing, suits clean environments, handles higher temperatures
• Cast iron — maximum load capacity, used in very heavy industrial applications

Match the wheel material to your floor type and environment for best performance and longevity.

FAQ’s

1. What is a castor wheel? 

A castor wheel is a wheeled unit that attaches to the base of trolleys, trucks, and mobile equipment. It can be fixed (moves in one direction) or swivel (rotates 360 degrees), and comes in a range of sizes and load ratings to suit different applications.

2. What's the difference between swivel and fixed castors? 

A swivel castor rotates 360 degrees for full manoeuvrability. A fixed castor moves in one direction only. Most trolleys use a combination of swivel castors at the front for steering and fixed castors at the rear for directional stability.

3. What are heavy duty castor wheels used for? 

Heavy duty castors are designed for equipment that regularly carries loads of 200kg or more. They have reinforced housings, stronger axles, and wider wheel faces compared to standard castors — built for industrial trolleys, heavy platform trucks, and workshop equipment.

4. What is the benefit of puncture proof tyres? 

Puncture proof tyres, solid rubber or foam-filled, eliminate the risk of flats entirely. They're lower-maintenance than pneumatic tyres and reliable for equipment used outdoors or on rougher surfaces, where puncture could be a recurring problem.

5. How do I know which castors to order? 

Check four things on your existing castor: fitting type (plate or stem), wheel diameter in mm, load rating, and wheel material. Match these to the product specifications listed on the page, and you'll get the right fit.

6. Can I upgrade to heavy duty castors on a standard trolley? 

In most cases, yes — as long as the fitting type and wheel diameter match. Upgrading a trolley's standard castors to heavy-duty castors when it's regularly overloaded is a practical fix that extends the equipment's life.

Browse the full range or get in touch if you'd like a hand choosing the right product for your setup at 0117 330 2277 or sales@sacktrucksdirect.co.uk,