Published: August 12, 2026 · Topic: sealing strip manufacturing process
Quick Answer
A custom sealing strip project normally moves through requirement review, profile or tooling evaluation, sample production, sample approval, bulk extrusion or secondary processing, agreed inspection and order-specific packing. The exact route depends on the profile material, cross-section, adhesive, cut or roll length, application and buyer requirements. The photographs on this page are authentic Onaseal factory images rather than stock or illustrative imagery.
1. Start With the Application, Not Only the Profile
Reliable production begins before material enters an extrusion line. A supplier needs to understand where the seal will be installed, how it is retained, the working gap, expected compression, movement, temperature and exposure conditions. For a replacement part, a perpendicular cross-section photo and an uncompressed sample are more useful than a single angled photograph.
For an efficient RFQ, buyers should provide the profile drawing or sample, mating-part dimensions, critical tolerances, material preference, hardness or density when known, color, roll or cut length, annual demand and first-order quantity. Adhesive backing, flocking, joining, labels and export packing should also be stated when required.
2. Tooling and Profile Development
Custom extrusions require the profile geometry to be translated into a manufacturable tool. Existing tooling may suit a standard section, while a new or modified cross-section can require tooling development. Thin walls, deep channels, sharp transitions, co-extruded materials and embedded carriers may affect feasibility and tolerance planning.
The drawing revision and approved sample should remain the common reference. Buyers should avoid approving a profile only from a catalog thumbnail because small differences in lip angle, channel size or bulb position can change fit and sealing performance.
3. Extrusion and Downstream Processing
During extrusion, the selected material is formed through the die into a continuous profile. Process settings and downstream treatment depend on the material and section design. The operator monitors the line while the profile proceeds through the required production stages.
For B2B purchasing, the important question is not simply whether a line exists. The buyer and supplier should agree which characteristics will be checked: cross-section, critical dimensions, visible surface condition, length, adhesive placement, carrier position or other project-specific features.
4. Adhesive Backing and Roll Preparation
Secondary operations can include adhesive application, release-liner handling, rewinding, cutting, joining or other finishing steps. Adhesive selection should be based on the customer's substrate, surface condition, installation temperature and service environment. A generic “strong adhesive” claim is not a substitute for application testing.
5. Inspection Should Follow the Approved Requirement
There is no single inspection plan for every rubber, foam, PVC, silicone or brush profile. A useful quality plan identifies the characteristics that matter to the assembly and defines how often they are checked. Typical checkpoints may include material or batch identification, profile dimensions, surface condition, roll or cut length, quantity, labels and packing arrangement.
| Checkpoint | Buyer should define | Reference |
|---|---|---|
| Profile geometry | Critical width, height, wall, lip, bulb, channel and tolerances | Approved drawing or sample |
| Material | Material family, hardness or density target and required documentation | Project specification |
| Secondary operation | Adhesive location, liner, cut length, joint or other finish | Approved sample and packing specification |
| Packing | Roll length, quantity, labels, cartons and pallet request | Purchase order requirements |
6. Finished-Goods Storage and Shipment Preparation
Finished profiles may be supplied in coils, reels, cartons or cut lengths depending on the shape and customer request. Packaging must protect the profile from deformation, contamination and avoidable handling damage. Label content, carton arrangement and pallet requirements should be confirmed before shipment rather than assumed after production.
Questions Buyers Should Ask a Sealing Strip Manufacturer
- Can the supplier review both the profile and the mating-part geometry?
- Will a physical or production sample be approved before bulk production?
- Which dimensions and visible characteristics will be included in the agreed inspection plan?
- How will adhesive, cut length, roll length, labels and packing be specified?
- Which material or inspection documents are available for this particular project?
- How will drawing, sample or packaging changes be controlled for repeat orders?
Prepare a Better RFQ
Send a perpendicular profile drawing or uncompressed sample, application photographs, mating dimensions, material requirements, order quantity and packing request. Use the Onaseal RFQ form, review our custom profile measurement guide, or submit your project for review.
Frequently Asked Questions
What information should a buyer send before custom seal production?
Send a perpendicular cross-section drawing or physical sample, critical dimensions and tolerances, application photos, material preference, required length, quantity and packing requirements.
Why is sample approval important for a custom extrusion?
Sample approval gives the buyer and manufacturer a shared reference for profile geometry, fit, appearance and agreed acceptance points before bulk production.
Are the factory images on this page authentic?
Yes. The photographs were supplied by Onaseal and show actual factory equipment, tooling storage, product inventory and production activities.