Quick answer: a conveyor belt is identified by geometry, not by the code on the paperwork. Work out the family first (modular belt, flat top chain, radius belt or spiral chain plate), then the surface, then the pitch. A photo of the top and the underside plus one measured pitch will usually settle the series. A part number on its own often settles nothing, because most of the numbers buyers hold are internal machine builder codes rather than belt specifications.
Start with what you actually have
Replacement enquiries arrive in four shapes, and each one gets you a different distance. It is worth knowing which shape you are in before you start asking suppliers, because it tells you what the next step has to be.
| What you have | How far it gets you | What it cannot settle |
|---|---|---|
| A part number from an order or an ERP export | Sometimes the family and pitch, if it happens to be a belt maker's own code | Width, surface, underside guides, material. Machine builder codes carry none of this. |
| A photo of the belt running | Family and surface type, which rules out most of the catalogue | Pitch and thickness. A photo has no scale unless something known is in the frame. |
| A module or an offcut in your hand | Everything, with a caliper | Nothing, provided you also record the overall width of the belt on the machine. |
| Only the machine, still running | Family, surface, width, and the sprocket count | Pitch, unless you can measure the belt in motion or reach a return section. |
The order matters. Family, then surface, then pitch. Buyers who start at the pitch often measure the right number on the wrong kind of product.
First fork: is it a belt or a chain?
This is where most misdirected enquiries begin. Two products that look similar in a photo are built and priced in completely different ways.
A plastic modular belt is assembled from moulded modules threaded onto hinge rods, brick laid across the width. You can build almost any width from it, which is why width is a specification rather than a catalogue option. Price follows area.
A flat top chain, also called table top chain, is a single narrow strand of hinged plates. It comes in fixed plate widths, commonly 82.6, 114.3 and 152.4 mm, and you run several strands side by side when you need a wider bed. Price follows length.
Two more families sit alongside those.
| Family | How to recognise it | Typical position on a line |
|---|---|---|
| Straight running modular belt | Modules bricked across the width, rods visible at every pitch, runs in a straight line only | Main transport, washdown, cooling, draining |
| Radius belt | Slotted rod holes so the inside edge collapses; the belt bends flat around a curve | Curves and U turns inside one level |
| Flat top chain | One narrow strand, plates hinged end to end; a side flexing version also turns | Bottle, can and packaging handling |
| Spiral chain plate | Built for a spiral tower, climbs while turning around a drum | Freezing, proofing, cooling towers |
If your line turns a corner, check the second column before you go any further. A radius belt and a straight running belt with the same pitch are not interchangeable, and a spiral tower needs neither of them.
What a part number can and cannot tell you
We see two kinds of numbers, and they behave very differently.
The first kind is a belt specification. It carries a series number, a surface abbreviation, and often a width, so a supplier who knows the system can read the geometry straight out of the string. Our note on modular belt naming conventions covers how those codes are built.
The second kind is a machine builder's material code. It looks like a part number, it sits in the ERP system, and it identifies a purchasing record rather than a product. A string shaped like 0-9xx-xx-xxx-x is an accounting key. Nobody outside that company can decode it, and no amount of searching will turn it into a pitch.
A code that combines digits with letters such as FT, FG or RR is usually the first kind, because those letters describe the surface. A code made only of digits in dotted or dashed groups is usually the second kind. If your maintenance system exports both, send both. The belt code identifies the product, and the material code lets your own store find the record again when the replacement arrives.
One request we make often, and it saves a week: if the belt came with the machine, look for the spare parts list or the original invoice rather than for the belt itself. Those documents usually carry the belt code, the width and the metres, all three in one place, and a plant with a maintenance system almost always has them filed.
The three features that decide the mould
Once the family is settled, three features narrow the field to one or two candidates.
Surface. Photograph the top square on, in daylight, with the belt flat. A fully closed flat top, an open flush grid, a perforated flat top, a raised rib and a nub top are easy to tell apart in a photograph, and the surface alone removes most of the catalogue.
The underside. Turn a module over and photograph the back. This is the photo people skip, and it changes the tooling. Some belts carry moulded guide strips underneath that run inside the conveyor frame and hold the belt on line. A belt with those strips and a belt without them are separate moulds. Fit a flat bottomed belt to a frame built for guided running and it will wander off the sprockets within a shift.
Pitch. Rod centre to rod centre. Measure across ten hinges and divide by ten. Catalogue pitches cluster at 12.7, 15.24, 19.05, 25.4, 27.2, 38.1, 50.8 and 57.15 mm, and several series share 25.4 mm, so rod diameter and module thickness are what separate them. Rod diameters run mostly at 4.8, 5, 6.3 and 8 mm. The full method is in our guide on measuring a modular belt for replacement, and the range is set out in the series index.
If the line cannot be stopped
Plenty of enquiries come from plants that will not open a running machine for a measurement, which is reasonable. Three things can still be recorded from outside.
- Overall belt width, taken across the frame.
- A photo of the drive sprocket with the tooth count, plus the shaft diameter and whether the bore is round or square. Tooth form and pitch are linked, so a clear sprocket photo carries real information about the belt.
- A photo of the return run underneath, which usually shows the underside without any dismantling.
If a spare belt or an offcut is anywhere in the store, measure that instead. A belt that has carried load for years elongates slightly, and a spare gives a cleaner reading.
What to send us
The list below is what we need to name a series and quote against it. Partial information is still worth sending; we will tell you which item is missing rather than guess.
- One photo of the top surface, one of the underside, one of the sprocket if you have access
- Pitch in millimetres if you could measure it, and the belt width
- Metres required, and how many belts
- Any code you hold, from the order, the ERP export or the machine manual
- What the belt carries, and whether the line runs wet, oily, hot or cold
- Whether sprockets are included; if so, tooth count, shaft diameter and bore type
Photographs travel better through WhatsApp than through email, and a caliper or a ruler laid in the frame makes any photo far more useful. You can also send everything through the contact form. We confirm the series and the accessories before anything is priced, because a belt quoted against the wrong mould helps nobody.
