If the part slides, rubs, or takes abrasive wear, use UHMW. If it holds liquid, gets welded, or just needs to be a rigid food-safe surface, use HDPE. Everything below is why.
They look almost identical on the rack and they are both polyethylene, which is why they get confused. But they solve different problems. UHMW has molecular weight in the millions, which buys enormous abrasion resistance and very low friction — and costs you tensile strength and any ability to weld or bond. HDPE is stronger in tension, welds into leak-tight assemblies, and costs meaningfully less per sheet.
Choosing on price alone is how a chute liner gets replaced three times in one year. Choosing UHMW for a tank is how you find out nothing sticks to it.
This is why UHMW stops carryback and bridging in a chute. It runs at roughly a third the friction of dry steel with no lubrication at all, which also means no grease near clean product. HDPE is slick, but not slick enough to be a sliding-wear material.
HDPE carries more load in tension and it welds. Those two facts together are why every fabricated tank, launder, and containment weldment that leaves our shop starts as HDPE or polypropylene rather than UHMW.
Polyethylene moves more than any other material we stock. Röchling publish the same coefficient range for both grades — 150 to 230 × 10<sup>-6</sup>/K, which is roughly thirteen to nineteen times steel — so treat UHMW and HDPE as moving the same amount rather than assuming one is more stable. On a 96″ panel across a 70°F swing that is most of an inch. Slot the bolt holes, leave the ends free, and never trap a PE sheet tight between two fixed points.
| Property | UHMW | HDPE |
|---|---|---|
| Abrasion resistance | Roughly 6–10× HDPE | Good, not exceptional |
| Coefficient of friction | 0.10–0.22 | 0.20–0.29 |
| Tensile strength | 3,100–4,000 psi | 4,000–4,600 psi |
| Impact, notched Izod | No break | High, but it does break |
| Weldable | Hot-gas only, at reduced joint strength | Yes — hot-gas and extrusion, full strength |
| Bonds with adhesive | No | No |
| Service temperature | −200°F to +180°F | −50°F to +180°F |
| Water absorption | < 0.01% | < 0.01% |
| Chemical resistance | Excellent | Excellent |
| FDA / food contact | Yes, virgin grades | Yes, natural & white (also NSF) |
| Relative cost | Higher | Lower |
| Machines & routs | Yes | Yes |
Typical published values for virgin UHMW-PE and HDPE sheet, offered as a design starting point rather than a specification. For load-bearing, containment, or regulated work, ask and we will supply mill certification for the specific sheet.
HDPE costs less per square foot. That is real and it matters on a big containment job. But on a wear part, the sheet price is the small number — the big numbers are the labor to swap it and the production you lose while the line is down.
A liner that lasts three times as long is not three times the cost of ownership; it is a third of the downtime. If you are pulling and replacing the same part on a predictable schedule, that interval is the number to optimize, not the invoice. Tell us how often you are changing it now and we will size the material and thickness against that instead of guessing.
Tell us what the part has to survive — what is moving across it, how fast it is wearing now, whether it holds liquid, and whether it goes near food — and we will tell you which one to use, including when the answer is neither. We stock both in Sparks and cut them to size the same day, so this is a conversation with material on the floor behind it, not a catalog lookup. Call (775) 358-8211 or send us the details.
Sometimes that is genuinely the right call — low-abrasion service, easy access, cheap labor to swap. But if the changeover means shutting a line down or working at height in a chute, the sheet price stops being the deciding number. Work out what an hour of downtime costs you and the comparison usually answers itself.
HDPE. It is the industry standard, it is NSF certified, it is stiffer, and it costs less. UHMW is overkill and the extra wear life buys you nothing on a board that gets resurfaced or replaced for hygiene reasons anyway.
UHMW, in nearly every case. Better abrasion life, lower friction so material sheds instead of building up, and it does not ring like a steel liner. Thickness depends on the ore, the drop height, and the impact angle — send us those and we will size it.
No. Even though both are polyethylene, the molecular weight difference means they do not fuse reliably. Mixed assemblies get mechanically fastened. If you need a welded structure, design it in HDPE or polypropylene and bolt UHMW wear surfaces to it — which is a very common and very sensible combination.
In black, yes, both. Natural and white grades will chalk and degrade in sustained UV. Specify black or a UV-stabilized grade for anything permanently outdoors, in either material.
Both are stocked in our Sparks warehouse — both from 1/8″ through 1″ on the rack and sourced to 4″ — UHMW in natural and black, HDPE in white, black, and natural. Cut to size same day. A wear part is not something you should wait a week for.
Whatever you need — one piece or one hundred, a quick cut or a full fabrication run — we're here. Serving Northern Nevada since 1979.