Silicone gasket compression is not a single value that can be selected without the surrounding assembly. The gasket section, available gap, mating surfaces, fastener arrangement, housing stiffness, movement, and inspection method all affect how the seal is reviewed. A useful RFQ therefore gives the supplier enough drawing and assembly context to discuss the proposed material and geometry while keeping an early target subject to project review.
Forvard Tech reviews custom Silicone Gaskets for civil industrial equipment. Buyers can also read about compression set and long-term sealing and submit controlled drawings through the RFQ form. The checklist below helps engineering and procurement teams prepare a clearer compression review.
1. Show the free-state gasket section
Begin with the gasket geometry before installation. The drawing should identify the nominal thickness or profile section, width, corner details, holes, joints, beads, lips, and any local changes in cross-section. For a molded or joined gasket, mark the parting, joining, or transition areas that could affect assembly review.
Do not rely only on a finished assembly drawing in which the gasket is hidden between components. A separate free-state view helps distinguish the intended gasket geometry from the installed gap. State the drawing revision, units, scale, and which file governs if a CAD model and a two-dimensional drawing differ.
2. Define the mating gap and compression direction
The RFQ should show the distance available for the gasket after the assembly is closed. Identify the nominal gap, expected variation, compression direction, and whether the surfaces remain parallel. If the gap changes around the perimeter, provide representative sections or a gap map instead of one general dimension.
Clarify whether the gasket is compressed axially, radially, or through a more complex motion. Sliding installation, insertion over a flange, or closing a hinged cover can introduce handling and friction questions that are not visible in a static section. The supplier needs the installation sequence as well as the final position.
3. Describe both mating surfaces
Provide the material and surface condition of the components that contact the gasket. Note relevant texture, coating, paint, plating, molded finish, or machining pattern, and identify steps, grooves, fastener holes, or discontinuities near the sealing path. Photos can support the drawing, but they should not replace controlled dimensions.
Flatness and stiffness also matter. A thin cover may deflect differently from a rigid frame, especially between fasteners. Rather than assuming uniform compression, show the cover structure, unsupported spans, and locations where the assembly is expected to contact a hard stop.
4. Mark hard stops and compression controls
If the design uses a groove, shoulder, spacer, boss, sleeve, or other feature to limit closure, identify it clearly. State which surfaces establish the closed position and which dimensions control that relationship. Without this information, the gasket may be treated incorrectly as the only element controlling the final gap.
Also explain whether assembly tools use torque, displacement, force, or a physical stop as the process control. A torque instruction alone does not fully describe gasket compression because fastener friction, cover stiffness, and tightening sequence can change the assembled condition. The RFQ should present the actual control method for project review rather than asking for a universal torque recommendation.
5. Map fasteners and closure sequence
Show fastener type, size, quantity, spacing, edge distance, and tightening pattern where these influence closure. For clips, latches, bands, or clamps, provide their positions and the direction of applied load. Identify areas farthest from the closure points because they may need separate fit or contact review.
If the assembly is opened for maintenance, describe the expected removal and reinstallation process. This does not establish a service-life promise; it helps the supplier understand whether the part is installed once, inspected periodically, or handled during routine access. Any reuse decision should be confirmed through the project’s own inspection and validation plan.
6. Explain pressure, movement, and exposure
State what the seal is intended to separate and whether the pressure is internal, external, differential, intermittent, or primarily related to splash or dust protection. Describe vibration, thermal movement, joint movement, or repeated opening when relevant. Avoid converting a general application description into an unverified sealing rating.
List contact media, cleaning methods, temperature exposure pattern, and surrounding materials. These inputs support material-route review, but compatibility and performance must be evaluated for the actual formulation, conditions, duration, and test method. If documentation is required for a target market, identify the exact project and document need instead of requesting broad certification coverage.
7. Identify critical inspection points
Mark dimensions that control fit, sealing contact, hole alignment, groove seating, and edge position. Explain whether the flexible gasket should be measured free-state, supported on a fixture, or assembled to representative hardware. Measurement method and conditioning can affect results, so the drawing should connect each critical characteristic to a practical inspection condition.
For the assembled review, identify how engineering will check closure, contact, visible gaps, alignment, leakage, or functional behavior. State who supplies the mating parts and test fixture. Acceptance criteria should refer to the controlled drawing and agreed test method, not to an isolated website statement or an uncontrolled reference photo.
8. Separate targets from approved specifications
Early RFQs often contain target thickness, hardness, compression, or material family. Label these as targets when they remain open to supplier review. After sample and assembly evaluation, record the approved drawing revision, material designation, inspection notes, and any retained reference sample used by the project.
This distinction prevents preliminary values from becoming accidental blanket promises. It also gives procurement a clearer basis for comparing quotations: suppliers can respond to the same geometry, interfaces, exposure notes, validation plan, and documentation request.
9. Prepare the RFQ package
A complete package normally includes the gasket drawing and CAD file, assembly section, mating-part information, gap range, hard-stop details, fastener map, installation sequence, application and exposure summary, critical inspection points, validation method, packaging needs, and current revision history. List open questions separately so they can be resolved during drawing review.
Review the Silicone Gaskets page and the project-specific discussion of compression set and long-term sealing, then use the RFQ form to share the controlled files. Final material, dimensions, compression condition, inspection, documentation, and validation requirements should be confirmed for the specific assembly and operating environment.