Rubber Gasket Sample Policy MOQ | OEM Supplier

If you are sourcing custom rubber gaskets overseas, the sample policy and MOQ are the first two terms that determine whether your project timeline is realistic or doomed from the start. For a 500-meter trial run, most Chinese factories will quote a tooling fee and a per-meter price that assumes you will eventually order 5,000 meters. At Hunan Zhouxin Sealing Technology, we have shipped over 1,200 custom profiles to 40+ countries, and the gap between buyer expectation and factory reality is almost always a communication issue around CAD drawings and material specs — not capability.

What a Realistic Rubber Gasket Sample Policy Looks Like

A professional extrusion house will not hold your sample hostage. Our standard policy: samples are ready in 7-12 days after tooling approval, and we charge only the actual material and labor cost — typically USD 30-80 for a standard EPDM or silicone profile, plus freight. The tooling fee (USD 300-1,200 depending on die complexity) is separate and fully refundable after your first production order reaches 1,000 kg or 3,000 meters. This is not a marketing gimmick; it is how we filter serious OEM buyers from one-off shoppers.

Sample Lead Time Breakdown

MOQ: It Is Not a Fixed Number

Most buyers assume MOQ is a hard wall. In extrusion, the real constraint is the minimum batch size for the compounding machine — typically 50 kg of polymer matrix. For a small profile weighing 50 g/m, that is 1,000 meters. For a heavy 500 g/m seal, it is only 200 meters. Therefore, our MOQ is expressed in kilograms, not meters: 50 kg per color per compound for standard EPDM, NBR, and CR. For silicone and fluoroelastomer (FKM), the minimum is 25 kg due to higher raw material cost.

How to Lower Your MOQ

• Accept standard black or gray — custom colors require a separate pigment masterbatch batch.
• Combine multiple profiles — if you need three different cross-sections, we can run them in one batch if the compounds match.
• Order masterbatch rolls — 100-meter rolls instead of cut lengths reduce handling waste.

Sending Proper CAD Drawings: The Real Time-Saver

We receive about 40% of inquiry drawings that are unusable for extrusion tooling. Common errors: missing cross-section dimensions, no tolerance callouts, and 3D STEP files that do not show the 2D profile plane. Here is what we need on the first email: a DXF or DWG file of the exact cross-section (2D, closed polyline), material type, and Shore A hardness. If you have an assembly drawing, send it as a PDF reference, but the die is cut from the 2D profile only.

Critical Tolerance Specifications

In our Hunan factory experience, the most frequent rejection on first articles comes from buyers who specify a dense EPDM Shore A 70 but apply a tolerance of ±0.1 mm to a 30 mm-wide gasket. That is physically impossible with a single-durometer extrusion due to thermal shrinkage variation. We once had a German client insist on ±0.1 mm for a 40 mm profile; after three die iterations and a 2-week delay, they accepted ±0.2 mm, which still passed their IP66 cabinet test. Specify realistic tolerances, or you will pay for tooling rework that does not improve sealing function.

Material Verification: Numbers That Matter

Your drawing shows geometry, but the material spec determines longevity. For outdoor door sealing strips, we default to EPDM with a Shore A 60-70, tensile strength ≥ 8 MPa, and compression set ≤ 25% after 22 hours at 70°C (ASTM D395 Method B). If your application involves oil contact, switch to NBR — but know that NBR has poor ozone resistance, so do not use it outdoors unless you add a protective coating.

Common Elastomer Comparison for Gasket Extrusion

For thermal aging validation, we follow ASTM D573 — 70 hours at 100°C for EPDM, checking tensile and elongation retention (must remain ≥ 80%). If your cabinet seals require flame retardancy, we can compound with antimony trioxide to meet UL 94 V-0, but note that this raises durometer by 3-5 points and increases cost by 8-12%.

Tooling Cost and Die Ownership

Tooling is a one-time cost, not a recurring expense. A standard open-cell sponge die costs USD 350-600; a dense profile with a metal insert channel costs USD 800-1,200. The die is precision wire-cut from H13 steel and polished to reduce friction. You own the die after the refundable condition is met, and we store it free for 5 years. If you modify your design later, the new die is charged at 70% of the original price.

Packing and Export: What Arrives at Your Dock

Overseas buyers often forget that packing affects both cost and performance. For door sealing strips and silicone series, we pack in reinforced cartons with poly bags inside — 100-200 kg per carton to avoid deformation. For WPC profiles and long rigid seals, we use wooden crates with foam spacers. Standard export packing is seaworthy, but if you need vacuum packing for silicone (to prevent dust adhesion), specify it — it adds 5% to packing cost but is worth it for cleanroom applications.

Frequently Asked Questions

What is your MOQ for a custom rubber gasket?

Our MOQ is 50 kg per compound and color for EPDM, NBR, and CR. For silicone and FKM, it is 25 kg. In meter terms, this ranges from 200 to 1,500 meters depending on the profile's weight per meter. If your initial order is smaller, we can supply from stock profiles or ask you to pay a small batch surcharge of USD 100.

How long does a sample take to produce?

Standard sample lead time is 7-12 days from drawing approval, including die machining and first-run vulcanization. If you need a sample within 5 days, we can expedite with a rush fee of USD 80, provided the profile cross-section is under 50 mm and does not require special compounding.

What extrusion tolerance can you guarantee?

For dense rubber profiles under 6 mm, we guarantee ±0.15 mm; for 6-25 mm, ±0.25 mm; above 25 mm, ±0.40 mm. Sponge rubber tolerances are looser by nature — typically ±0.50 mm. Tighter tolerances are possible but require secondary grinding or cooling fixture adjustments, which adds 10-15% to the unit price.

How do you pack custom gaskets for export?

Cut lengths are coiled and taped every 300 mm, then packed in poly bags and reinforced cartons (max 25 kg per carton for easy handling). Long profiles over 2 meters go in wooden crates. We mark cartons with your PO number, material grade, and Shore A hardness. For sea freight, we add desiccant packs to prevent mold on natural rubber compounds.

Is the sample fee refundable?

Yes, the tooling fee is 100% refundable when your cumulative production order reaches 1,000 kg or 3,000 meters within 12 months. The sample material fee (USD 30-80) is not refundable but is deducted from your first production invoice if you place an order within 60 days.

Send your CAD drawing for a 24-hour quote — include the cross-section DXF, material type, and target Shore A hardness, and we will return a full technical datasheet with pricing, tooling cost, and a sample policy that fits your procurement cycle.