A well-written rubber gasket RFQ saves time, reduces samples and prevents the most common cause of rework: missing dimensions. This guide shows how to specify rubber gasket dimensions, material, hardness, tolerances and flange details so the supplier can quote accurately the first time.
Minimum Information for Any Gasket RFQ
At minimum, include these seven items:
- Inner diameter (ID) and outer diameter (OD) — or the gasket outline if it is not a simple ring.
- Thickness — the uncompressed gasket thickness, not the groove depth.
- Material — EPDM, NBR, VMQ silicone, CR neoprene, FKM or PTFE.
- Hardness — Shore A durometer, e.g. 70 Shore A.
- Quantity — per order and annual estimate.
- Application — fluid, temperature and pressure.
- Drawing format — DXF, PDF or STEP.
Gasket Drawing Best Practices
A good gasket drawing shows ID, OD, thickness, bolt-hole locations (for full-face flanges), and any cutouts or notches. If the gasket matches a flange standard such as ASME B16.21, state the nominal pipe size and pressure class rather than drawing every dimension from scratch.
For custom profiles, send a DXF file with a single closed polyline per gasket. Remove dimensions and title blocks from the cutting layer to avoid translation errors.
Gasket Tolerance Guidelines
Tolerances depend on cut method:
- Die-cut: ±0.1–0.2 mm
- Flashcut: ±0.1–0.3 mm
- Waterjet: ±0.2–0.5 mm
Tighter tolerances increase cost. Specify only what the joint actually needs. For most static flanges, ±0.3 mm is adequate.
Flange Class and Bolt Pattern
For pipe flange gaskets, include the flange standard (ASME B16.21, DIN EN 12560), nominal pipe size and pressure class. For full-face gaskets, the bolt-hole pattern must match the flange exactly. For ring gaskets, only the ID/OD and thickness matter as long as the OD clears the bolts and the ID covers the bore.
Material and Hardness Notes
Match the material to the media first, then choose hardness. A 70 Shore A compound is the default for most industrial flanges. Use softer grades for rough surfaces and harder grades for high pressure or small extrusion gaps.
Common RFQ Mistakes
- Sending a photo without dimensions.
- Confusing groove depth with gasket thickness.
- Omitting the fluid or temperature.
- Requesting die-cut tolerances on a waterjet prototype.
- Reusing an old drawing that no longer matches the flange.
Submitting the RFQ
Upload your drawing and specification to our custom rubber gasket quote page or use the general request a quote form. We respond within 24 hours with material recommendation, cut method, tooling cost and lead time.
Q1: What is the most common information missing from a gasket RFQ?
The operating fluid and temperature. Without them, the supplier cannot confirm material compatibility, which is the leading cause of gasket failure.
Q2: Can I quote a gasket from a physical sample instead of a drawing?
Yes. Mail the sample or send high-resolution photos with a ruler for scale. We can reverse-engineer ID, OD and thickness, but material identification may require testing if it is not marked.
Q3: What tolerance should I specify for a prototype gasket?
Use waterjet or flashcut tolerances of ±0.2–0.5 mm for prototypes. Die-cut tolerances are only achievable after tooling is made.
Q4: How do I know if I need a full-face or ring gasket?
Full-face gaskets suit flat-face flanges and softer materials like cast iron or plastic. Ring gaskets suit raised-face steel flanges. Match the gasket profile to the flange facing.
Q5: Should I include bolt torque in the RFQ?
Bolt torque is not needed for quoting, but it is useful for design review. If you are unsure, our engineers can recommend torque based on gasket material, thickness and flange size.