Specialty Casters
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Keyed Drive Wheels
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Skid Wheels & Casters for RVs
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Shopping Cart Wheels & Casters
Band Equipment Casters & Wheels
Low Profile Casters
Cart Wheels & Casters
Toolbox Caster Sets
Bakery & High Temperature Casters
Kitchen Prep Table Caster Sets
Wire Shelving Casters
Silent Glide Casters
Extreme-duty casters carry 10,000 to 40,000 lb per caster — the load class of turbine generators, large press frames, aerospace fixtures, shipyard sections, and steel-mill transfer. Every build is kingpinless, dual-row tapered roller, forged construction, and matched to an engineered floor. This is procurement, not an off-the-shelf purchase.
Extreme duty casters carry 10,000 lb and up per caster, on wheel diameters from 8" to 36", and are specified when a single caster is a structural member of the load path rather than a mobility accessory. CasterHQ stocks 254 Hamilton configurations in this class, from 2,200 lb dual-wheel rigs up to 40,000 lb per caster on Ultra Maxi-Duty and Extreme Maxi-Duty forgings. Above roughly 10,000 lb the failure mode moves off the tread and onto the raceway, the fork weldment, and the mounting plate, which is why series and rig matter more here than wheel material. For the broader 1,000 to 16,000 lb range, start from heavy duty casters.
Capacity at a fixed envelope changes with tread and with the ULTRA rating on the same Hamilton casting. These are stocked configurations, not catalog maximums.
| Wheel Size | Tread / Series | Capacity Per Caster |
|---|---|---|
| 10" x 3" dual | Duralast | 5,400 lb |
| 12" x 5.5" dual | Rubber | 4,600 lb |
| 12" x 5.5" dual | Polyurethane | 9,000 lb |
| 12" x 5.5" dual | Polyurethane ULTRA | 10,800 lb |
| 13.5" x 5.5" dual | Rubber | 6,200 lb |
| 13.5" x 5.5" dual | Polyurethane | 10,200 lb |
| 13.5" x 5.5" dual | Polyurethane ULTRA | 15,600 lb |
| 16" x 5" dual | Polyurethane ULTRA | 15,600 lb |
| 18" x 9" kingpinless | Polyurethane / Black Rubber | 15,600 lb |
| 8" x 4" dual | Forged Steel (EMD2) | 40,000 lb |
| 18" x 5" dual | Nylast (UMD2) | 40,000 lb |
| 22" x 16" / 28" x 12" / 36" x 20" | Polyurethane (Ultra Maxi-Duty) | 40,000 lb |
Read that table sideways, not down. At 13.5" x 5.5" the same rig carries 6,200 lb on rubber, 10,200 lb on polyurethane, and 15,600 lb on ULTRA polyurethane. Tread choice moves capacity by a factor of 2.5 at identical mounting dimensions. Conversely, an 8" x 4" forged steel dual reaches the same 40,000 lb as a 36" x 20" polyurethane. When overhead or under-deck clearance is the constraint, forged steel buys capacity in a fraction of the envelope, at the cost of floor finish and noise.
Divide by three, then apply a dynamic factor. Total static weight plus payload divided by three, not four, because one caster leaves the floor during a floor-joint or dock-plate transition. Then multiply by 1.5 to 2.0 for tow speed, shock, and off-center loading. A 60,000 lb rig on four casters needs 20,000 lb per caster before the dynamic factor, and 30,000 to 40,000 lb after it.
Push force, not capacity, decides whether it moves. Rolling resistance scales with load and falls with wheel diameter. Doubling the wheel from 12" to 22" at the same load cuts required push force substantially, which is why the Maxi-Duty range runs large diameters even where a smaller wheel would carry the weight.
Kingpinless above 10,000 lb, without exception. A kingpin is a single shear member. At this class the raceway carries the load through a hardened, sealed path instead. All Hamilton Maxi-Duty and Extreme Maxi-Duty rigs in this range are kingpinless.
Confirm the plate and bolt pattern before the wheel. Extreme duty top plates run far larger than standard industrial plates, and the mounting structure often needs reinforcement to accept them. Send the equipment drawing and we will confirm plate fit before the order ships.
Sizing a rig above 10,000 lb per caster? Contact CasterHQ with total weight, floor condition, tow method, and duty cycle.
Forged steel holds the highest capacity in the smallest envelope and tolerates weld spatter, chips, and debris. It marks concrete, transmits shock into the load, and is loud. Polyurethane, including the DuraGlide, Duralast and UltraGlide series, protects the floor, lowers push force, and covers most of the 9,000 to 40,000 lb range. Nylast carries the highest point load of the polymer treads on smooth hard floors and reaches 40,000 lb in the UMD2 dual rig. Black rubber gives the quietest roll and the most shock absorption, at roughly 60 percent of the polyurethane rating in the same envelope.
254 Hamilton configurations held in Mansfield, TX: 127 swivel and 127 rigid, 88 of them dual-wheel, across the Maxi-Duty, Ultra Maxi-Duty and Extreme Maxi-Duty series. Wheel diameters run 8" to 36". Our application engineers cross OEM part numbers, verify plate and bolt pattern against the equipment drawing, and confirm dynamic rating for towed applications before the order ships. Most in-stock configurations leave the same business day.
