QHDC Australia appreciates that everyone has a different level of understanding when it comes to wheels and castors. So we thought we’d create a simple guide to illustrate the different terminology used in the industry. Below are a list and breakdown of common wheels and castors terminology.
Wheel
Wheels consist of tread/tyre, wheel centre/rim, and a wheel bearing. Depending on their nature, the wheels have different load capacities, rolling resistance and rolling qualities. The special characteristics of the individual wheel will depend on the series of the wheel.
Designations:
1 = Tread/tyre
2 = Wheel centre/rim
3 = Hub
4 = Wheel bearing
Dimensions:
D = Wheel diameter
d = Axle bore diameter
T1 = Hub length
T2 = Wheel width
Swivel Castor
Swivel castors are vertically rotatable and make appliances, etc. maneuverable. A fork (swivel fork) is fitted to the fitting element by a swivel head (swivel bearing). To enable a smooth swivel motion of the fork, the wheel is generally fitted with a horizontal distance between the axis of the swivel bearing and the wheel (offset). If correctly dimensioned, the offset allows a smooth swiveling of the castor without additional tools as well as directional stability. Swivel castors can be equipped with brake systems to lock:
– the rotary motion of the wheel
(wheel brake)
– the rotary motion of the wheel and the
swivel motion of the fork
(wheel and swivel head brake)
– the swivel motion of the fork
(directional lock).
Designations:
1-3 = Swivel bracket
1 = Top plate fitting
2 = Swivel head (swivel bearing)
3 = Swivel fork
4 = Wheel
5 = Wheel axle
Dimensions:
H = Total height/mounting height
F = Offset
A,B = Plate dimensions
a,b = Bolt hole spacing
d = Bolt hole diameter
Fixed Castor
Fixed castors provide directional stability for appliances, etc. and cannot be swivelled.
Designations:
1 = Fixed bracket
2 = Wheel
3 = Wheel axle
Dimensions:
H = Total height/mounting height
A,B = Plate dimensions
a,b = Bolt hole spacing
d = Bolt hole diameter
Press-on band/tyre
Press-on bands/tyres consist of different elastomers and are equipped with a steel ring or a steel insert. Depending on their nature, press-on bands/tyres have different load capacities, rolling resistance, and rolling qualities.
Designations:
1 = Tread/tyre
2 = Steel-band
Dimensions:
D = Outer diameter
d = Inner diameter
T2 = Width