Heavy duty caster wheels, specified like it matters.

Ask three suppliers for heavy duty caster wheels and you will receive three different products wearing the same photograph. One quotes a 2.2 mm fork where another quotes 4 mm. One fits a plain bore where the drawing showed a precision ball bearing. One rates capacity on a static test and the other on a dynamic rolling test. The prices differ because the casters differ — and the difference only shows up six months later, on a warehouse floor, under load. CASTOVELLA's heavy duty line exists to remove that ambiguity: the specification is locked in writing first, samples are tested against it, and only then is a price attached.

The heavy duty range

The line is built around polyurethane tread on a cast iron core — the combination that carries heavy loads without destroying finished floors. Configurations cover swivel, rigid and swivel-with-brake, on top plate mountings, in the sizes US equipment actually uses:

Every size is available across the swivel / rigid / brake matrix; the product pages show the lead configurations importers order first. If your equipment needs a stem or bolt-hole mounting instead of a top plate, say so in the RFQ — mounting is part of the locked specification, not an afterthought.

Why polyurethane on cast iron carries this line

The cast iron core gives the wheel its load-bearing spine and its heat path under sustained rolling; the polyurethane tread gives floor protection, quiet running and cut resistance that a plain iron or hard rubber wheel cannot match. Tread hardness is the dial: softer compounds grip and cushion, harder compounds roll easier and carry more. We quote hardness as a stated Shore range and check the sample against it, because a heavy duty caster wheel that arrives two hardness grades softer than quoted will flat-spot under standing load — a failure buyers often blame on the floor.

Bearings, raceways and forks: where heavy duty is decided

• Bearings. Precision ball bearings for equipment that must start rolling under load with one hand; roller bearings where brute capacity matters more than start-up effort; plain bore only where the buyer explicitly accepts it.
• Swivel raceways. The raceway is the part nobody photographs. We state whether it is a single or double ball race and whether it is hardened — an unhardened raceway brinells under shock load and the caster starts to steer like a shopping cart with a bent wheel.
• Forks and plates. Fork leg and top plate thickness are stated in millimetres on the quotation. On an 8 inch extra heavy duty caster, fork thickness is the difference between a five-year wheel and a five-month one.

A note on US import duty for this line

Most heavy duty caster wheels do not classify under HTS 8302.20: Chapter 83 Note 2 limits that heading to casters of 75 mm diameter or less, or wider wheels under 30 mm width. A 100–200 mm wheel of 40–50 mm width falls under 8716.90.30 as the residual heading — at the same 5.7% MFN rate, and with the same China additional-duty stack. Any supplier quoting you a duty advantage from the heading alone is quoting fiction. Our full caster tariff guide walks through the rule, the rulings and the current stack.

Who buys this line

US caster distributors building a private-label heavy duty range; material-handling and equipment OEMs who need a repeatable wheel across production runs; scaffold and racking suppliers pairing wheels with their own frames. What they share is a specification they intend to keep — and a supplier who will hold it across orders, with batch traceability when a question comes back.

The specification we lock before quoting

A quotation is only comparable when the specification underneath it is fixed. For this line — as for every CASTOVELLA line — the written quotation locks these six variables, and the production sample is checked against them before bulk production is approved:

• Wheel diameter and width — width is both a performance variable and the US tariff classification variable; it is measured on the sample, not copied from a catalogue.
• Tread material and hardness — stated as a Shore hardness range, so the bulk shipment can be checked against the approved sample.
• Bearing type — plain, roller or precision ball bearing, named on the quotation; bearing swaps are the most common silent downgrade in this industry.
• Fork and top plate thickness — measured in millimetres and stated, because fork flex is where cheap heavy duty casters fail first.
• Load capacity and test method — capacity per caster with the test convention named (EN 12532 / ANSI ICWM), never a bare number.
• Finish and hardware — zinc plating, stainless grade or coating stated per component, not per marketing photo.