Compression and HCR injection in Apt (France, 550 m² ISO 8). LSR injection at Top Tech Silicones (Italy, 1,500 m², 6 LSR presses · group speciality). Weights from 0.1 g up to more than 1 kg, moulds from 1 to N cavities, post-cure in sealed ovens. 2K two-shot plastic + silicone overmoulding on the Italian line.
Compression closes the cycle in the oven with one part per window — ideal for large masses, high hardnesses and short runs. HCR injection takes pre-formulated solid mass for medium parts with multiple cavities. LSR injection opens the route from short runs to millions with tight tolerances, thin walls and complex geometry. The three coexist within the group and pick the plant by volume, certification and technique.
Pre-weighed solid HCR in a ball, vertical press closes the hot mould, the mass flows into the cavity under pressure and vulcanises with the platen temperature. Long cycles (4-15 min). Large parts, thick sections, high hardnesses. Short runs and prototypes. Tooling cheaper than injection.
Pre-mixed solid mass injected into a hot mould from a screw. 1-N cavities. Cycle 60-180 s. Medium weights (1-200 g). Takes advantage of Progress's Shore A tuning and mix traceability. The group's only HCR line (Apt).
Bicomponent liquid A+B mixed in a static head and injected into a cold mould with hot closure. Vulcanisation by mould temperature (180-220 °C). Short cycles (20-60 s). Tight tolerances, complex geometry, thin walls. From prototype to millions. 6 presses in Italy (Top Tech Silicones) + 2 in France (Apt).
Apt (France) gathers compression, HCR injection and two LSR presses in 550 m² of ISO 8 cleanroom — the only plant in the group where extrusion and moulding share the same floor. Top Tech Silicones (Lombardy, Italy) concentrates the group speciality in liquid silicone: 1,500 m² of cleanroom with 6 LSR presses and a 2K two-shot overmoulding cell for cosmetics, automotive and class II medical devices.
Each variable pushes the part towards one of the three techniques. The design office (D27 · /capacidades/diseno-utillajes) recommends the combination before quoting tooling.
| Variable | Compression | HCR injection | LSR injection |
|---|---|---|---|
| State of the mass | Pre-weighed solid HCR in ball | Pre-mixed solid HCR | Two-component liquid A+B |
| Injection | Manual onto hot cavity | Screw + nozzle | Static mixer + nozzle |
| Mould temperature | 160-200 °C (hot closure) | 160-200 °C (hot closure) | 180-220 °C (hot closure) |
| Typical cycle | 4-15 min | 60-180 s | 20-60 s |
| Usual cavities | 1-4 | 1-16 | 1-64+ |
| Weight per part | 5 g — 1 kg+ | 1-200 g | 0.1 g — 200 g |
| Dimensional tolerance | ISO 3302-1 M2 standard | ISO 3302-1 M2 / M3 | ISO 3302-1 M3 tight |
| Typical series | Prototypes · short series | Medium series | Short series to millions |
| Geometry | Massive parts, thick walls | Medium parts | Complex · thin walls · undercuts |
| Overmoulding | No (HCR only) | Plastic/metal HCR | 2K plastic-silicone · silicone-silicone |
| Group plant | France (Apt) · 550 m² ISO 8 | France (Apt) · the group's only HCR site | Italy 6 presses · France 2 presses |
| Certification | ISO 9001 + 13485 | ISO 9001 + 13485 + EN 9100 | ISO 9001 + 13485 + EN 9100 |
Whatever the chosen process, the part goes through the same control and certification stages. The mix comes from our own banbury (/capacidades/formulaciones-silicona), the tooling from the integrated mechanical workshop (/capacidades/diseno-utillajes), the cleanroom applies post-cure and issues the lot's technical sheet.
From a tenth of a gram (small medical device, miniature O-ring, press optics) to over a kilo (technical seals, bellows, structural part). The upper limit is set by the press and post-cure oven; compression is the best option for large masses.
1-cavity moulds for prototypes, 4-8 cavities for medium runs, up to 64+ cavities on small LSR parts with automatic demoulding. Design and machining in our own workshop (Apt) — no external supplier, no file transfer.
3 stainless steel ovens with sealed tanks for post-cure under controlled air flow. Removes residual volatiles, stabilises mechanical properties and prepares the part for food (FDA, CE 1935), medical (USP VI, ISO 10993) or aerospace (EN 9100) certification.
Each moulding run travels with a unique lot number from the first charge of mix to packing. Mechanical sheet of the compound (extensometer, Shore A durometer, compression set), raw-material CoA, dimensional control drawings and certificate of conformity archived for ten years for audit.
The press fleet works equally well for one-off prototypes, short runs of a hundred units, medium batches of several thousand or continuous production into the millions. What changes between scenarios is the number of mould cavities, the degree of demoulding automation (manual or integrated robot) and the post-cure schedule.
On the Italian LSR side, moulds can carry up to 64+ cavities with automatic ejection and robotic handling for parts of a few grams. In French compression, the same mould can vulcanise prototype runs of 50 units and annual runs of 5,000 without reconfiguring the press. Each lot leaves with the compound's mechanical sheet, control drawings and certificate.
The two Progress group cleanrooms are complementary, not equivalent. Each technique lives where its optimal fleet sits; the design office assigns the plant at project start.
| Capability | Apt · France · Progress | Lombardy · Italy · Top Tech |
|---|---|---|
| Cleanroom area | 550 m² | 1,500 m² |
| Cleanroom class | ISO 8 (NF EN ISO 14644) | Dedicated cleanroom cosmetic + medical |
| Compression | Yes · vertical presses | — |
| HCR injection | 1 press · the group's only one | — |
| LSR injection | 2 presses | 6 presses · group specialty |
| 2K bi-material overmoulding | — | Plastic-silicone · silicone-silicone |
| Post-curing | 3 sealed stainless-steel ovens | Ovens dedicated to the LSR line |
| Extrusion and moulding coexist | Yes (only plant in the group) | No (LSR moulding specialisation) |
| QMS certification | ISO 9001 · ISO 13485 · EN 9100 | ISO 9001 · ISO 13485 |
| Lead sectors | Medical · railway · aerospace | Cosmetic · class II medical · automotive |
Send us the drawing or sketch, critical dimensions, estimated run size, Shore A hardness, sector (medical, food, rail, automotive, cosmetic) and applicable standard. We confirm the recommended technique (compression, HCR or LSR), the group plant, the number of cavities, tooling lead time and the certifications available. No order commitment.
