Bolt hole castors attach through a single central bolt rather than a plate, which makes them the fitting for tubular legs and frames with no flat surface. Everything on this page is our industrial grade: a pressed steel fork with a double ball race, a single M12 fixing, and four wheel materials in 100mm and 125mm sizes, rated from 70kg to 250kg per castor. All are available swivel or braked.
The majority of our wheels are moulded here in the UK using our own tooling, and we offer next day delivery when you order by 2pm.
It is a castor secured to the equipment by one bolt passing through a central hole in the swivel head, instead of the four fixing holes of a plate. That single bolt hole is what makes the fitting the usual choice for tubular steel trolleys, stands and frames: the head sits on the end of the tube, the bolt passes through, and there is no plate to accommodate.
Industrial versions are usually M12, with M16 and M20 at 150mm and above; institutional and medical are generally M10 or M12. Everything here takes an M12 bolt. One limitation applies to the whole fitting type: a bolt hole castor can be swivel or braked swivel, but never fixed. A single bolt through the centre would simply let a fixed castor spin, so if you need one that tracks in a straight line, look at our industrial plate fitting castors instead.
The fork and fitting are the same across the range. The choice is the wheel, and the material decides which floors it suits, how much noise it makes and how easily it rolls under load.
A white nylon wheel in 100mm rated to 70kg and 125mm rated to 100kg swivel and 250kg braked. Nylon is hard wearing with low rolling resistance and carries weight well, works in wet conditions and resists chemicals. Being hard it transmits more noise than a rubber tyre and can mark softer floors, so it is ideal for workshop and warehouse floors rather than finished ones. Commonly used on bakery frames, tool chests, tool stands and sack trucks.
A non marking grey rubber tyre in 100mm rated to 70kg and 125mm rated to 100kg. It gives low rolling resistance with smooth, quiet movement, and because it is non marking it is the one for finished and polished floors. Widely used in manufacturing and healthcare, on trolleys, bakery frames, tool stands and industrial refuse bins.
Commonly known as a flight case castor. The blue elastic tyre dampens vibration for quiet running, and combines the softness of rubber with easier rolling under load. Supplied in 100mm rated to 70kg, and used across manufacturing and medical equipment as well as flight cases, tool chests and refuse bins.
A black rubber tyre in 100mm rated to 70kg. It minimises vibration for quiet movement with low rolling resistance, and is widely used across manufacturing on trucks, trolleys and sack trucks. The one thing to check is the floor: black rubber can mark light floors, where the grey tyre will not.
Every 100mm castor on this page is rated to 70kg, and the 125mm castors to 100kg, with one exception: the 125mm nylon wheel braked castor is rated to 250kg. Add up the weight of the equipment plus its maximum load and divide by three, not four: on an uneven floor only three castors reliably carry the load at any moment, so dividing by three builds in a margin. On that basis a set of four 100mm castors is sized for a total loaded weight of 210kg, and a set of four 125mm for 300kg. Brakes should be rated for the same load as the wheel, and always size up when the load is heavy.
Castors are named by wheel diameter, not overall height. The 100mm size stands 130mm from the floor to the top of the fitting, and the 125mm size 155mm. If you are working to a set clearance, or matching a castor already on the equipment, measure the total castor height rather than the wheel.
Fitting is a single M12 bolt through the central hole and the end of the tube or frame. The bolt itself is chosen for the tube or frame it passes through.
Where a leg is a hollow tube with nothing to bolt through, the answer is an expanding adaptor. It grips inside the open end of the tube, in round or square profiles, most commonly 19mm and 22mm, so the castor can be fitted to a metal leg without drilling. Bolt hole castors can be supplied with solid stems or round and square expanding adaptors to suit different tube sizes. Stems and adaptors suit the 100mm and 125mm castors on this page; on larger wheels they are not strong enough for the load.
Replacing a worn castor is straightforward if you measure three things: the bolt hole size, the wheel diameter and the total castor height. If you are unsure, send us a photograph and a measurement and we will identify what you need.
Every castor here is a swivel castor: the head rotates through 360 degrees so the wheel turns to follow the push, giving easy mobility in a confined space. The braked version adds a brake to hold the castor when the equipment is loaded or parked. If the brake is the priority rather than the fitting, our braked and lockable castors page brings the braked options from every range together.
The industrial range is designed to cope with the more rigorous stresses in the workplace. Typical applications include trucks and trolleys, bakery frames, tool stands and tool chests, sack trucks, industrial refuse bins and flight cases, across manufacturing and healthcare. If the equipment stands on tubular legs and each castor will carry between 70kg and 250kg, this is the range.
Not every bolt hole fitting is industrial. Our budget bolt hole castors cover 50mm and 75mm grey rubber tyre wheels with M8 and M10 fittings, rated to 50kg and 60kg, for desks, mobile display cases and light trolleys. For hospital and care equipment, our medical castors include nylon body and twin wheel versions in M8, M10 and M12. Where height is the constraint, the 35mm low level castors give 120kg per castor on an M10 fitting at just 58mm overall height. And if the fork on your existing castor is sound and only the wheel is worn, we sell replacement castor wheels to fit existing brackets.
For larger orders we can tailor almost any aspect of a castor, including the bolt hole size, and volume pricing is available on trade and bulk purchases. We supply single castors as readily as full pallets. Contact us with quantities and specifications for a quote.
Every industrial castor on this page takes an M12 bolt. Industrial castors at 150mm and above are also made in M16 and M20, and institutional and medical castors are generally M10 or M12.
Use an expanding adaptor. It grips inside the open end of a hollow tube, round or square, and gives the castor something to be secured to without a hole being drilled through the leg. Measure the inside diameter of the tube first: 19mm and 22mm are the most common sizes.
No. The fitting is swivel or braked swivel, never fixed. Fixed castors are only made in plate fitting, and most trolleys use two of each: fixed at one end for tracking, swivel at the other for steering.
A plate castor uses a flat plate, secured through four fixing holes, to spread the weight across a wider area. It is the most rigid fitting and the strongest, which is why industrial castors are mostly plate. A bolt hole fitting suits tubular legs with no flat surface. If the equipment offers a flat surface, plate is the stronger choice; if it stands on tube, bolt hole is the practical one.
Both spellings describe the same product. Castor is British English; caster is American. UK suppliers, including QED, use castor.
Not sure which fitting or wheel you need? Talk to us - we help customers find the right castor every day.