Why Material Specs Fail: Hanwha EVA 1316, EVA Foam Board, and Polyurethane vs Rubber Casters

I'm a quality compliance manager at Hanwha. I review technical documentation before it reaches customers—roughly 200 individual datasheets and application notes every year. In Q1 2024, I sent 11% of first submissions back for revision. The most common reason? The numbers were right in one context, but the customer was going to use the material in a different one.

That's why the same problem keeps appearing in products made from EVA foam board, in grades like Hanwha EVA 1316, and in every “polyurethane vs rubber casters” comparison I've read.

It's not because the material is bad. It's because a spec sheet is not a usage manual.

The surface problem: You did everything right

You found an EVA foam board manufacturer with good reviews. You checked the official Hanwha downloads page and pulled the technical data for Hanwha EVA 1316. Tensile strength looked fine. Density seemed right. Compression set was within range. Then the prototype board crushed after two weeks of testing.

Or you have a caster application and did the obvious search: polyurethane vs rubber casters. Polyurethane looks stronger. Rubber looks quieter. You pick the one with the higher load rating. Then the wheels stop turning after exposure to a cleaning chemical they meet every day.

The surface problem looks like material selection. That's not the real problem.

The deeper problem: Datasheets are snapshots, not promises

Every property on a datasheet is measured under specific conditions. Hanwha EVA 1316 has standard values for melt flow rate, density, and tensile strength. Those values are useful. They're also measured on a lab specimen, not on your EVA foam board after it's been mixed with a crosslinking agent, expanded in a mold, and cut to 25 millimeters thick.

The same EVA resin can produce a completely different final board if the converter changes the blowing agent, raises the press temperature, reduces cooling time, or specifies a different skin layer. I say this from experience: when I first started in quality, I assumed a datasheet with good numbers meant the final part would have good numbers. It took me about four years and 150 supplier audits to understand that the gap between polymer and finished product is where most quality problems are born.

To be fair, a datasheet isn't supposed to include every possible process condition. It can't. But that's exactly why you should never treat it as a complete guarantee.

For casters, the same trap is hidden in the phrase “polyurethane vs rubber casters.” Polyurethane compounds range from a soft elastomer to a hard, almost plastic material. Rubber can mean natural rubber, SBR, EPDM, neoprene, or a proprietary blend. “Polyurethane” from one supplier does not automatically outperform “rubber” from another. The compound recipe, not the family name, determines what happens on your floor.

What most people don't realize is that suppliers mix polymer, fillers, plasticizers, and curatives to hit a target price and processability. Two suppliers can both call their wheel “polyurethane” and deliver products that behave completely differently.

What this really costs you

Skipping this context is expensive. In 2022, a customer who manufactures EVA foam board asked us to help with a field failure. Their resin was Hanwha EVA 1316—at least according to their purchasing records. Our lab confirmed the resin itself was fine. But the board failed after 1,000 compression cycles because the converter had raised the blowing agent ratio to cut density. The finished boards didn't meet the original compression set requirement. All 8,000 units were rejected. The redo cost roughly $22,000 in production time, retesting, and expedited logistics. The converter saved a little money on density. The customer paid for it many times over.

For casters, the cost of a wrong choice is often quieter. Rubber wheels on an oil-contaminated floor can swell and mark. Polyurethane wheels on an uneven concrete floor can chatter and transfer vibration to sensitive equipment. That's not a win for “polyurethane vs rubber” in general. It's a mismatch between material and environment. Over a year, the mismatch shows up as downtime, floor damage, and replacement purchases—not one dramatic failure.

Then there's the time cost. You have to re-request, re-test, and re-explain to your team why the first spec didn't work. (Not to mention the emails.)

A more useful approach: Define the boundary conditions

The fix isn't more research. It's better questions.

For EVA foam board, before comparing EVA foam manufacturers on price or brochure numbers, define:

• What must the board do at the end-use thickness? Standard tests are usually done on standard boards. Your board is not standard.
• How much compression set can the application tolerate?
• What happens if the density varies by 10%? Would your packaging still protect the product?
• Can the supplier show lot traceability to the resin grade? If they say “we use Hanwha EVA 1316,” ask for resin purchase records and process control data.

For casters, define the environment before you compare polyurethane vs rubber casters:

• What chemicals does the wheel meet? Oil, solvents, mild soap, nothing?
• What is the floor surface? Smooth concrete, rough concrete, steel, tiles?
• What is the load per wheel and the average travel speed?
• What noise level is acceptable?

Then test actual wheels on your actual floor. A chart can start the conversation. It should not finish it.

The supplier who knows their limits is worth more

Here's something I've learned to value: a supplier who tells you where their expertise ends.

Hanwha is a polymer materials company. We make EVA, polypropylene, polyethylene, polycarbonate, and many other grades, and we publish technical data and support documents on the Hanwha downloads page. But we're not the ones running your foam press or designing your caster assembly. When an application calls for a material or process outside what we can confidently support, we say so. I've seen suppliers who promise “we can do everything”—and then quietly substitute a different grade when the specified one isn't available. That's a much bigger risk than a supplier admitting a limit.

I'd rather work with an EVA foam manufacturer who says, “We don't do molded foam, but here's a converter who does” than one who takes the order and figures it out later. Same for a caster supplier who says, “Rubber is better for your oily floor than polyurethane” even though they sell more polyurethane. That kind of honesty protects your project. It also makes me trust everything else they say.

What to do starting this week

Pick one product decision you're facing. If it's an EVA foam board, don't stop at the Hanwha downloads page. Print the data sheet, highlight the test method notes, and send them to the foam manufacturer with one question: “How does this property change at my thickness and density?” If they can't answer, keep looking.

If it's a caster choice, delete the generic “polyurethane vs rubber casters” article from your head and write down your operating conditions first. Then ask a supplier who asks questions back to you.

And if a supplier says, “This part of your application isn't our strength,” listen. That's not a lost sale. That's the best risk assessment they can give you. (Pretty rare, I know.)

It took me a few years and a few expensive field failures to learn this. You don't have to wait that long.