The yoke (also called the fork) is the metal frame that holds the wheel axle on either side and connects up to the swivel section, top plate, or stem. It's the structural piece that actually carries the wheel.
Yokes are stamped or forged steel on most industrial casters — forged yokes generally handle higher shock loads. The yoke width has to match the wheel width and hub, or the wheel will bind or wobble.
Mainly relevant when diagnosing a failed caster or replacing just the wheel — a bent or cracked yoke is a common failure point under overload or impact.
Reusing a bent yoke. A yoke that’s been overloaded once can be weakened even if it still looks straight — when in doubt, replace the whole caster rather than just the wheel.
Stamped vs. forged yoke — does it matter?
Forged yokes are generally stronger under shock and repeated heavy loads; stamped yokes are lighter-duty and more common on lower-capacity casters.
Can I replace just a wheel without replacing the yoke?
Yes, if the yoke is undamaged and the new wheel matches width and hub — but inspect the yoke for cracks or bending first.