A bakery in Melbourne needed about 400 m of spiral belt for a bread cooling spiral. The original belt had rough edge welds with burrs, and the guide strips were wearing. From the customer's sample, the belt was measured, a new sample made to the same pitch, rod and link — with cleaner welds — and compared before bulk production.
The buyer's main complaint was weld quality: the rod-end welds on the belt edge were rough, with burrs. Plastic shavings built up along the edge and the blue guide strips were scored. A replacement had to fit the existing spiral exactly — and not repeat the problem.
No drawing was used. A section of the original belt was sent, and every dimension that decides fit was read with a caliper — pitch, rod, link thickness and link size — so the new belt runs on the same drum, sprockets and guides.
A sample was made to the measured values and checked with the same tools before bulk production. The readings match the original within normal measuring tolerance.
| Checked | Customer's original | New sample |
|---|---|---|
| Pitch | 27.41 mm | 27.40 mm |
| Rod diameter | 5.03 mm | 5.00 mm |
| Link thickness | 2.70 mm | 2.70 mm |
| Edge weld | Rough, with burrs | Smooth, cleaned |
Caliper readings from the photos below. Final values follow the drawing confirmed with the buyer.
The fix the buyer asked for: clean edge welds
Same pitch, rod and link as the original — but the rod-end welds on the new belt are finished smooth, with no burrs to catch the guide strips. Weld finish was one of the points checked on the sample before bulk.
Nylon sprockets were supplied with the belt. Outside diameter, bore and pin were measured, then a sprocket was run on the new belt to check tooth engagement before the crates were closed.
| Location · year | Melbourne, Australia · 2023–2024 |
|---|---|
| Industry · equipment | Bakery · spiral cooling tower (bread cooling) |
| Problem | Rough rod-end welds with burrs on the original belt; plastic shavings and scored guide strips |
| Starting point | Section of the original belt — no drawing |
| Belt supplied | Spiral belt, about 400 m, 760 mm wide, SUS304, pitch 27.4 mm, rod 5.0 mm, flat-head welded edge, electropolished |
| Sprockets supplied | Nylon, outside diameter about 161 mm, measured and run on the new belt |
| Checked before bulk | Pitch, rod, link thickness and link size compared with the original on the same caliper; weld finish |
| Checked before shipment | Sprocket running and engagement test on the new belt |
| Packed | Lined export crates with spare rods; shipping list on each belt |
1.A worn sample is enough — if the right dimensions are read
Pitch, rod diameter, link thickness and link size decide whether a spiral belt fits the drum, sprockets and guides. Reading them on the original with a caliper replaced the missing drawing.
2.Weld finish is a fit issue, not only cosmetics
Burrs on rod-end welds scraped the plastic guide strips. Matching dimensions alone would have repeated the problem; the weld finish was specified and checked on the sample.
3.Replace sprockets with the belt and run them together
A new belt on worn sprockets can jump or wear early. Here the sprockets were measured, supplied and run on the new belt before shipment.
4.Compare original and new with the same tools
Original 27.41 mm pitch vs new 27.40 mm; rod 5.03 vs 5.00 mm; link 2.70 vs 2.70 mm — read the same way, so the buyer can check the numbers, not a promise.
✓ Evidence on this page: 8 site photos of the original belt, 8 caliper readings on the original and 7 on the new sample, 3 sprocket measurements, a sprocket running test video with stills, and shipment photos. Customer name, order numbers and the original brand are withheld.
Replacing a spiral belt without a drawing?
Send a short section of the old belt, or photos with a caliper in the picture — usually a reply within 8 hours.
Yes. In this project a section of the old belt was enough: pitch, rod, link thickness and link size were measured with a caliper, a sample made and compared before bulk production.
The same dimensions are read on the original and on the new sample with the same tools, and the buyer approves the sample before production. Readings and photos are shared at each step.
Yes, as long as the fit dimensions stay the same. Here the rod-end welds were finished smooth on the new belt while pitch, rod and link stayed matched to the original.
Yes. Nylon sprockets were measured and supplied with the belt, and a sprocket was run on the new belt to check engagement before shipment.
No. Cases show country, city and year only. The buyer's name, address and the original belt brand are not published.