The part a belt weigher's accuracy leans on
We specify it
Tell us what is in the conveyor and we work out the roller it needs, any make, any belt width from 600mm to 2400mm.
Weigh quality, not carry quality
Skimmed, balanced and matched as a set, to the required ISO standards.
Aligned on site
Set by our technicians so the whole weigh area runs true, which is what the accuracy actually depends on.
A belt weigher can only weigh what its rollers let it feel. If a weigh roller is out of round, out of balance or dragging in its bearings, the weigher reads that instead of the material, and no amount of calibration will take it out.
We work out which rollers your weigher needs, supply them to weigh quality rather than carry quality, and have our technicians align them on site so the weigh area sits true. That last part is the one most often skipped, and it is the reason two weighers with identical rollers can read differently.
Where a conveyor needs a frame we do not stock, we make a custom weigh quality idler frame for it, either as part of a new system or to bring an existing weigher up to scratch.
Weigh quality means measured, matched, balanced and aligned
A carry roller has one job: hold the belt up. A weigh roller has to do that without adding anything of its own to the reading, and the difference is in the tolerances rather than in the look of the thing. This is why a conveyor roller off the shelf, fitted into a weigh frame because it was the right diameter, quietly costs a site accuracy for years.
Concentricity and run out
Each roller is skimmed so the belt sits at a constant height as it turns. A high spot puts a repeating wave through the load signal that looks like real material.
Balance
An unbalanced roller adds its own vibration at belt speed, which the load cells feel and the integrator cannot tell from load.
Matched as a set
Rollers on a weigh idler are supplied together so they share the same diameter. A mismatch tilts the belt line across the weigh span.
Bearing drag and seals
Heavy duty bearings with proper seals, because a stiff or contaminated bearing drags on the belt and shows up as a false load.
Alignment in the weigh area
Our technicians align the weigh idlers so the rollers sit level with each other and in line with the idlers either side, giving one true plane across the whole weigh area. Rolling height is measured and shimmed, not assumed. A correctly made roller in a badly aligned frame still reads badly.
What we supply
Every set is specified to the application rather than picked off a shelf, so this is the range we can supply rather than a list of part numbers.
Weigh quality rollers
- Belt widths 600mm to 2400mm
- One, three or five rollers per idler
- Roller length and case thickness to suit the application
- Steel, steel hybrid, HDPE, aluminium and FRAS roller cases
- Heavy duty bearings, sealed for conveyor duty
- Skimmed, balanced and supplied as a matched set
Weigh quality idler frames
- Hot dipped galvanised mild steel as standard
- Stainless steel with a bead blast finish for harsh environments
- Stainless jacking screws for height and alignment adjustment
- Screw adjustment, cam adjustment or fixed, to match the weigher
- To suit angle, C channel, box and I beam stringers
- Custom frames made here when a conveyor needs one
- Supplied with the shim kit to set rolling height on installation
What goes with them
- Shim kits in galvanised and stainless, in 1mm, 3mm and 6mm
- Bed rolls and return rollers where the weigher uses them
- Belt lifters in three sizes for changing rollers safely
- Tie rod kits, clevis blocks and spherical washer sets
Rollers and idlers for whatever weigher you have
Most of the rollers we supply go into somebody else's belt weigher. We work from the measurements off the idler that is in the conveyor now, so the make of the weigher matters less than the numbers do, and an obsolete weigher is not a problem.
Belt weighers we regularly supply weigh quality rollers and idler frames for include:
Seven measurements and we can quote it
These are the same seven dimensions our technicians record on every weigher we maintain, taken off the roller itself. Send them with the belt width and we can quote without a site visit. Ask us for our roller measurement form and we will send one over so nothing gets missed, or if you would rather we came and measured, we can do that too.
- 1Diameter
Outside diameter of the roller case, in mm.
- 2Face length
The length of the case itself, end to end.
- 3Back to back
Between the inside faces of the two mounting slots or brackets.
- 4Total length
Overall, across the shaft ends.
- 5Shaft diameter
The round part of the shaft, in mm.
- 6Slot
The mounting slot width the shaft drops into.
- 7Across flats
The flat to flat measurement on the machined shaft end. This is the one most often given as the shaft size by mistake, and the two are different numbers.
Add the number of rollers in the idler, the belt width, the trough angle and the stringer type, and a photo of the idler in place if you have one. If you are already an Accurate Industries customer, we most likely have all of it on file already and you only need to tell us the conveyor.
Request the measurement formIf it can be kept running, we can usually supply the part
Plenty of the belt weighers still running on Australian sites have outlasted the company that sold them. Brands get bought, product lines get dropped, and the support that came with the machine quietly goes with them. Ask for a part and the answer is that it is no longer available.
That is not where it ends with us. We supply the parts to get a weigher working again, like for like where the part still exists and a sound equivalent where it does not. Rollers and idlers are the easiest case, because we specify them from the measurements rather than from a part number, so a discontinued model is no obstacle. And if a weigher has reached the point where replacing it makes better sense than patching it, we will tell you straight and quote that instead.
Tell us what is in your conveyor and we will quote it
We supply and align weigh quality rollers and idler frames across mining, quarrying and other industries right around Australia, on our own weighers and on everybody else. Send the measurements, ask us for the form, or ask us to come and take them.
Weigh quality roller frequently asked questions
What is a weigh quality roller?
It is a conveyor roller made to much tighter tolerances so it does not add anything of its own to the weight reading. It is skimmed so it runs true, balanced so it does not vibrate at belt speed, matched in diameter to the other rollers on the idler, and fitted with sealed heavy duty bearings so it does not drag. The roller is only half of it though. Our technicians then align the weigh idlers on site so every roller sits in one true plane across the weigh area and in line with the idlers either side, which is what turns a good roller into an accurate weigher. A standard carry roller dropped into a weigh frame will hold the belt up perfectly well and cost you accuracy.
Can you supply weigh rollers for another make of belt weigher?
Yes, and that is most of what we supply. We work from the measurements off the idler in your conveyor rather than from a maker part number, so we can supply for weighers that are obsolete or no longer supported.
What do you need from me to quote a set of rollers?
Seven measurements off the roller: diameter, face length, back to back, total length, shaft diameter, slot, and across flats. Then the number of rollers in the idler, the belt width, the trough angle and the stringer type. A photo of the idler in place helps. Ask us for our roller measurement form and we will send one over so nothing gets missed. If we already maintain the weigher, we will have all of it on file.
How often should weigh quality rollers be replaced?
As a rule of thumb we recommend every 12 to 18 months on a conveyor running 24/7, and longer where the duty is lighter, but the real answer comes off the equipment rather than the calendar: we inspect the rollers at every service and calibration visit and confirm what actually needs changing. The signals are a weigher that will not hold its zero between calibrations, a repeating wave in the load reading, wear flats or grooving in the roller case, and any roller that is stiff or noisy by hand with the belt off. It is worth staying ahead of, because a roller that fails in service does not just cost you accuracy: a seized roller can damage the belt and take the conveyor out, and unplanned downtime on a production conveyor costs far more than the rollers do.
What is the difference between a weigh idler and a carry idler?
The carry idlers hold the belt along the conveyor. The weigh idlers sit inside the weigh frame, are carried on the load cells rather than on the stringers, and are set to present the belt at exactly the same height as the idlers either side. A weigh idler frame is built for correct weight distribution and carries jacking screws so that rolling height can be set precisely on installation.
Do you supply the idler frame as well as the rollers?
Yes, either separately or as a complete weigh quality idler with the rollers fitted and the shim kit to set it. Frames come in hot dipped galvanised mild steel as standard, and in stainless steel with a bead blast finish for harsh environments. Where a conveyor needs something we do not stock, we make a custom frame for it, either as part of a new system or to bring an existing weigher up to scratch.
Get in touch with us and let us deliver best in class outcomes to you
Core to our operation is developing relationships with our customers so we can understand their problems, concerns and goals, to ensure we deliver the best outcomes possible. We provide accurate, reliable and honest service and information, and ensure the correct equipment and solutions are provided every time, without fail.
Accurate Industries, Australia's belt weigher and weightometer specialists
Contact us now →Technical notes: how a belt weigher works, and what happens during a calibration visit.