Dual-wheel casters split the load across two wheels on a shared axle. Each wheel runs cooler under sustained load, the contact patch doubles, and the swivel raceway sees less deflection — the spec for towline carts, AGVs, dock operations, heavy industrial transport, and anywhere a single-wheel caster would deflect or fail under continuous duty. 228 dual-wheel configurations stocked across three capacity tiers, with Hamilton Nylast™ cast nylon and Duralast polyurethane leading the heaviest tiers.
One wheel carrying the full load. Simpler bearing assembly, lower cost, sufficient for cart applications under 1,500 lb per caster on smooth indoor concrete. Heat builds up in the wheel hub under sustained towline pulling because all load goes through one bearing race.
Failure mode: bearing race wear from continuous duty, wheel deflection under shock loads at the rated capacity edge.
Two wheels on a shared axle, each carrying half the load. Bearing race deflection drops by 60-80% at the same total caster capacity. The wider contact patch (2x wheel face) distributes load better on uneven floors. Required spec for towline operations above 2 mph and for any continuous-duty industrial cart above 2,000 lb per caster.
Failure mode: typically axle wear in 10+ years of daily towline use — dramatically longer service life than single-wheel.
Take total cart load (cargo + cart deck weight), divide by 4 casters, and add a 30% safety margin for shock loads. For continuous towline duty, add 50% instead of 30%. If your math gives you 1,500 lb per caster, the 2,000 lb tier covers you with headroom. 2,500 lb per caster lands in the 3,000 lb tier. Above 2,500 lb per caster, jump to the 7,000 lb super-heavy tier.
For towline applications, motorized carts, or anything that runs daily under continuous duty: yes. Hamilton’s Nylast cast nylon wheels and Duralast polyurethane formulations are designed for the heat that builds up under continuous duty — generic dual-wheel polyurethane will soften and flat-spot under the same conditions. For occasional-use carts and stationary applications, generic dual-wheel poly works fine at 30-50% lower cost.
Nylast™ is Hamilton’s cast-nylon wheel material. The nylon is cast (not injection-molded) which gives a denser, more impact-resistant wheel that resists chemical attack and won’t flat-spot under prolonged static load. Capacity ratings run 2,000-10,000 lb per wheel depending on size. Used on aircraft ground support, military equipment, and the heaviest industrial transport applications. The Nylast premium typically runs 40-60% over standard polyurethane on aluminum at the same size.
Towline operation pulls carts at sustained speed (2-5 mph) through high-cycle direction changes. Single-wheel casters fail in towline use because the kingpin and bearing race see continuous shock loading — the wheel deflects, the kingpin works back and forth, and after a few months the kingpin loosens or shears. Dual-wheel design (combined with kingpinless construction at the heaviest tiers) eliminates both failure modes. See our Kingpinless Casters collection for kingpinless dual-wheel variants.
Yes — better than single-wheel, actually. The dual contact patch bridges gaps and seams that would catch a single wheel. For outdoor or rough-surface work, also consider dual-wheel PNEUMATIC casters (separate Heavy Duty Dual Wheel Pneumatic collection) where the air-filled tire absorbs additional shock from gravel and expansion joints.
Kingpinless single-wheel handles shock loads better than standard single-wheel by eliminating the kingpin failure point. But for continuous towline duty at high capacities (3,000 lb+ per caster), dual-wheel is still preferred because the load-distribution advantage compounds with the kingpinless raceway. The heaviest applications (aircraft GSE, military transport) typically spec dual-wheel kingpinless — both benefits combined.
Stock dual-wheel casters ship same day from Mansfield, TX before 3 pm Central. The heavier 7,000 lb tier and Hamilton super-heavy variants typically ship LTL freight. For application specification, towline analysis, or capacity sizing on a cart that hasn’t been built yet, call 844-439-4335 or email info@casterhq.com — a real engineer responds, not a chatbot.
