---
id: silicraft/okf/capabilities
type: capability-matrix
title: Five silicone grades — material families and process capability
last_updated: 2026-09-21
canonical: https://silicraft.lumorb.com/
---

# Five silicone grades

Each grade has a dedicated molding cell, its own QC station, and its own documentation trail. Medical parts never run on a kitchenware press — ever.

## Capability table

| Code | Grade | Durometer (Shore A) | Service range | Cure system | Process | Standards |
|---|---|---|---|---|---|---|
| FG-001 | Food-Grade | 30–80 | −40 °C to 230 °C | Platinum or peroxide | LSR injection, HCR transfer, HTV compression | FDA 21 CFR 177.2600, LFGB §31, EU 1935/2004, GB 4806.7 |
| MG-002 | Medical-Grade | 40–70 | −50 °C to 200 °C | Platinum (LSR) | LSR injection, HCR transfer; Class 8 cleanroom | ISO 13485, USP Class VI, FDA 21 CFR 211, ISO 10993, EU MDR Class I/II |
| EG-003 | Electronic-Grade | 50–80 | −60 °C to 250 °C | Platinum (LSR) | LSR injection | UL 94 V-0, RoHS, REACH, IPC |
| IM-004 | Infant & Mother | 20–50 | −30 °C to 180 °C | Platinum (LSR) | LSR injection; Class 8 cleanroom | EN 14350, FDA 21 CFR 177.2600, TPE-free, BPA-free |
| IG-005 | Industrial-Grade | 40–90 | −70 °C to 300 °C | Peroxide | HTV compression, HCR transfer; FKM and VMQ compounds | ASTM D2000, SAE J200, MIL-SPEC |

## Process capability matrix

| Process | Achievable tolerance | Cycle time | Multi-cavity ceiling | Best for |
|---|---|---|---|---|
| LSR injection (cold runner, balanced) | ±0.05 mm (≤50 mm feature) / ±0.10 mm (≤200 mm) | 30–90 s | 64 cavities | Medical, baby-care, food contact, electronic |
| HCR transfer (preform + closed runner) | ±0.10 mm / ±0.20 mm | 2–6 min | 16 cavities | Mid-volume parts needing tighter than HTV |
| HTV compression (hand-loaded + flash groove) | ±0.20 mm / ±0.30 mm | 3–8 min | 8 cavities | Large / thick-walled industrial seals |

## See also

- `company.md` — plants and certifications backing these capabilities
- `products.md` — 25 parts we mold, mapped to these grades
- `process.md` — how a project flows from drawing to pallet
- `compliance.md` — per-grade regulatory package

## Source

<https://silicraft.lumorb.com/okf/capabilities>