Silicone belts for hot processes up to 220 °C
Where silicone conveyor belts are used: baking, confectionery, shrink wrapping. Temperature range, non-stick properties and service life.
A silicone belt is the solution for sections where PVC and polyurethane soften or burn. Where product leaves the oven hot and its shape must be preserved, silicone withstands continuous contact with temperatures up to 220 °C. In this article we break down where a silicone belt is mandatory, what its limits are and how we select it for a specific process.
Why silicone for hot zones
Standard polymer belts are rated for moderate temperatures: PVC deforms already at +80 °C, polyurethane holds up to +90 °C short-term. Silicone elastomer keeps its elasticity and geometry from -60 °C to +220 °C, so it goes where other materials do not survive: at tunnel-oven exits, in shrink-wrap zones, on cooling tables right after baking.
The second advantage is the non-stick surface. Silicone has low surface energy, so dough, caramel, glaze and chocolate do not stick to the belt. This removes the need for constant oiling and simplifies cleaning. For confectionery lines this is critical: a stuck sugar layer quickly caramelises and turns into an abrasive that ruins both the product and the belt itself.
Where we fit silicone belts
On our projects a silicone belt appears in clearly defined sections:
- Baking — transporting hot bread and loaves from oven to slicer, feeding dough to proofing.
- Confectionery — removing cookies, wafers, gingerbread, glazing and depositing lines.
- Shrink wrapping — the belt passes through the heat tunnel together with packaged product.
- Cooling zones — receiving hot product where PVC would not survive the temperature swing.
- Semi-finished products — contact with fried or baked items.
Silicone is not intended for heavy bulk loads or abrasive products — there modular plastic or mesh belts take its place.
Temperature limits and construction
A silicone belt usually has a fabric carcass (polyester or fibreglass) with a silicone coating. A fibreglass carcass raises the upper working limit and reduces elongation under tension. Below is a comparison of typical belt materials by temperature.
| Belt material | Working range | Non-stick | Typical use |
|---|---|---|---|
| PVC | -10 °C … +80 °C | Low | Packaging, vegetables, fruit |
| Polyurethane (PU) | -30 °C … +90 °C | Medium | Open food products |
| Silicone on polyester | -40 °C … +180 °C | High | Confectionery, cooling |
| Silicone on fibreglass | -60 °C … +220 °C | High | Ovens, shrink wrapping |
| Stainless steel mesh | -100 °C … +400 °C | Medium | Ovens, roasting |
Engineer’s tip. Silicone holds 220 °C in long contact, but a peak heat above this limit cuts the lifespan severalfold. We always build in a 20–30 °C margin between the real product temperature and the belt’s rated limit.
What to watch when selecting
A silicone belt costs more than PVC, so a specification error is expensive. Before ordering we confirm four things. Contact temperature — not the tunnel air, but the surface of the product and the belt itself. Contact duration — seconds or minutes under heat. Joint type — for hot zones we make a vulcanised endless joint, since mechanical fasteners break down fast in an oven. Cleaning — even a non-stick surface is washed periodically, so the belt must withstand alkaline agents.
For direct contact with open product we choose silicone certified to EU 1935/2004 or FDA 21 CFR — this guarantees the food safety of the material. We covered belt selection by product in more detail in our article on conveyor belts.
Service life and maintenance
In the correct temperature regime a silicone belt lasts 18–30 months of continuous operation. The main causes of premature wear are overheating above the limit, abrasive product and incorrect tension. An over-tensioned belt on a fibreglass carcass cracks along the edge; an under-tensioned one slips on the drum and melts from friction. We recommend checking tension weekly and keeping a spare belt in stock, since its replacement requires precise calibration for the carcass temperature drift.
Silicone is sensitive to sharp edges: a single scratch from a metal scraper becomes a tear nucleus. So on silicone sections we fit scrapers of soft polyurethane and make guides from polymer, not steel.
Conclusion
A silicone belt is a specialised solution for hot zones of food production: ovens, shrink wrapping, cooling, confectionery. Its strengths are a wide temperature range up to 220 °C and a non-stick surface; its weaknesses are price and sensitivity to abrasion. If you have a hot-product section and are unsure which belt material will survive the process — get in touch, and we will select and calculate the belt for your line. More articles under the tag belts.
