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Metal conveyor belt
Compound balanced belts
Closed spiral belts, also called compound balanced belts: a dense metal mesh up to 4,000 mm wide for small products and heat treatment up to about 1,150 °C.
Request a closed spiral belt quote on tribelt.nlWhat a closed spiral belt is
A closed spiral belt is a metal conveyor belt woven so densely that its surface is nearly closed. In Tribelt's English product range it is listed as a compound balanced belt: several wire spirals are nested into each other and held by crossrods, with left- and right-hand spirals alternating so the belt runs straight. Tribelt makes every closed spiral belt in its own factory in Haaksbergen, the Netherlands.
The dense weave gives three things an open belt cannot: small parts stay on the belt, heat passes evenly into the product, and the belt stays stable under mechanical load. Tribelt tailors each belt to the process, whether the challenge is extreme heat, tiny products or unusual forces.
Specifications
- Pitch: 5.0 to 25 mm
- Mesh: from 5.0 mm down to a fully closed surface, depending on wire thickness
- Spiral wire: 0.8 to 2.0 mm diameter (type-dependent)
- Crossrod wire: 1.0 to 3.15 mm diameter (type-dependent)
- Wire strength: all common grades, 500 to 1,050 N/mm²
- Temperature: ambient up to approximately 1,150 °C
- Width: up to 4,000 mm, depending on type
- Build: alternating left- and right-hand spirals, including the multi-insert wide spiral belt WG-I
Applications
- Bakery: oven belts on which products are baked directly
- Pharmaceuticals: sterilisation tunnels
- Metal and glass: annealing, tempering, hardening, sintering and brazing
- Machine building: discharge belts under machining centres
- Heat treatment: curtains or screens that keep heat inside tunnel furnaces
- Decorative work: for example in jewellery
Benefits
- Produced in-house, giving Tribelt full control of quality and lead time
- Dense surface that carries very small products
- Uniform heat transfer for evenly treated products
- Strong enough for high temperatures and heavy loads
- Straight, predictable running
- Suitable for both food and industrial processes
Options
Side chains for a chain drive, flights or carriers, welded edges (on selected types), raised side plates for product guidance and PE1000 contact strips for quiet support.
Drive
Closed spiral belts are friction-driven, which calls for a drive roller of sufficient diameter. Tribelt advises on the support structure as well; a herringbone layout with PE1000 wear strips is a common choice that keeps the belt stable and reduces wear. See drive elements for rollers and sprockets, and the knowledge article on closed spiral belts for more background.
Specifications
| Versions | wide spiral belt WG-I (multiple inserts) |
|---|---|
| Belt width | up to 4000 (depending on type) mm |
| Pitch | 5.0–25 mm |
| Mesh opening | 5.0 mm down to fully closed |
| Spiral wire diameter | 0.8–2.0 mm |
| Crossrod wire diameter | 1.0–3.15 mm |
| Wire tensile strength | 500–1050 N/mm² |
| Maximum temperature | approx. 1150 °C |
Materials
- All common wire grades
- Stainless steel
- Heat-resistant alloys
Frequently asked questions
What is a closed spiral belt?
A closed spiral belt, sold in English as a compound balanced belt, is a metal conveyor belt with a tightly woven, almost closed surface. It is used where small products must not fall through or where heat has to reach the product evenly.
Which industries use closed spiral belts?
Bakeries use them as oven belts for baking directly on the belt, pharmaceutical plants in sterilisation tunnels, and metal and glass processors for hardening, sintering, annealing and heat shielding.
How hot can a closed spiral belt get?
With a suitable alloy, Tribelt closed spiral belts cope with process temperatures of about 1,150 °C.
Can Tribelt build a closed spiral belt to my specification?
Yes. Wire diameter, pitch, width up to 4,000 mm, flights, chain guidance and welded edges are all configurable. Because design and production stay in Tribelt's Haaksbergen factory, delivery can be planned around your project.
What does a closed spiral belt offer over an open one?
Better support for small products, less product loss, long life at high temperatures and a straight run thanks to mirrored left- and right-hand spirals.
Advice or a quote?
Quotes and advice go through Tribelt's official website.