Repair or replace a conveyor is a structural question, not a financial one. The answer comes from inspecting the conveyor, not from reading its build date. Steel does not get worse with age. The parts bolted to the steel do get worse with age. The belt, idlers, liners, and lagging can all be renewed on a frame that is still straight and still carrying the load. The decision depends on whether the frame is sound or is undersized, racked, and cracking.
The Short Answer
If the frame is sound and the worn parts are wear parts, repair the conveyor. Wear parts include the belt, idlers, bed slats, liners, lagging, bearings, sprockets, and chain. These parts are consumables that are meant to wear out. Renewing them on a sound frame is the cheapest work in the plant.
If the frame itself is undersized or cracking, replace the conveyor. No belt fixes a structure built too light for the load.
We make money either way. We fabricate new conveyors, and we repair and refurbish used equipment. So it is safe for us to say the next point. If a supplier quotes you a new line without looking at the old frame, they are trying to sell, not to find the problem.
The Test Is the Frame, Not the Age
Age is the wrong factor. A 30-year-old conveyor built heavy for the material it still carries is worth rebuilding. A six-year-old conveyor that was specified two weight classes too light for the material stream it was given is not worth rebuilding. The only question is whether the structure under the wear parts still carries the load. Your own people can answer that with a tape measure, a flashlight, and an hour.
The Inspection Checklist
While the conveyor runs, check four things from outside the guarding. The four things are belt tracking, drive and bearing noise, belt sag, and where material spills. Then shut down the conveyor. Lock it out. OSHA's control of hazardous energy standard, 29 CFR 1910.147, applies as soon as the work involves removing a guard or reaching into the machine. Go from the tail to the head. Write down your findings. Do not decide while you inspect. The pattern matters more than any single item.
1. Frame and Stringers
When the belt is empty, look along each stringer from the tail for a permanent bow. Steel that has yielded does not spring back. A curved stringer has carried more load than its design load. Then check that the frame is square. Measure the frame diagonally at several points along the run. On a frame that has not moved, the diagonals match. If the diagonals do not match, the frame is racked. Possible causes are a settled foundation, loose bolts, or an impact. A racked frame always works against the belt.
2. Cracking at Welds and Load Points
In welded steel, most fatigue cracks start at the welds. The reason is that the weld toe is a notch, and notches concentrate stress. Look at the welds and the load points: stringer-to-leg connections, gussets, hopper and skirtboard attachments, impact-zone crossmembers, and take-up frames.
One hairline crack at a single weld toe on a sound frame is a repair. Grind out the crack. Weld it again. Add material to remove the stress riser. Cracks at several load points along the same frame mean the structure is repeatedly loaded past its design load. Each time you repair a crack, another crack appears a few feet away.
3. Deflection Under Load
Watch the conveyor while it runs loaded, ideally during a surge. Some movement is normal in a long span. What matters is whether the frame recovers instantly. A frame that visibly flexes or pumps under a normal load is undersized. On a troughed idler conveyor, belt sag between idler sets is normally held near 2 percent of the idler spacing. More sag than this means low take-up tension, idler spacing that is too wide, or a structure that sags with the belt.
4. Bearings and Shafts
Hot, growling, or squealing bearings mean poor lubrication, contamination, or internal damage. Remove the covers. Darkened or gritty grease means contaminant has entered through the seals. Over-greasing often causes blown seals. Over-greasing pressurizes the housing and pushes the seal out. Reddish-brown powder around a housing is fretting. A cracked cast housing is at the end of its life.
Then check the shafts. Look for a bent shaft, a wallowed keyway, or a shaft worn undersize where a bearing has been spinning. A shaft that flexes under belt tension misaligns the bearings at both ends. All of these problems are repairable on a sound frame. Our guide to conveyor drive and bearing specs covers what to install.
5. Pulleys and Lagging
Lagging raises the friction between the belt and the drive pulley. Lagging is a wear part. If the lagging is worn smooth or torn off in strips, the belt slips on the drive pulley. The slip is then blamed on everything downstream. Re-lagging is routine. If rubber lagging keeps slipping or wearing out early in wet, abrasive service, use ceramic lagging. On the pulley, look for a dished or grooved shell, a crown worn flat, and cracking at the end discs. Pulleys are replaceable parts. A pulley is almost never a reason to replace the conveyor.
6. Belt Condition and Splice Count
When the top cover has worn through and the carcass is showing, the belt is at the end of its life. Exposed carcass absorbs moisture, frays, and delaminates. Hardened rubber, plies that separate or blister, and chronically frayed edges also show that the belt is at the end of its life.
Then count the splices. Ask how often they have been redone. If a belt keeps failing at or beside the splice, the carcass around the splice is fatigued. The next splice is made in the same fatigued material. Get a replacement belt. Belt strength is rated in pounds per inch of width (PIW). Running a belt above its rated working tension causes failures at or beside the splice. If the tension is correct and the belt still keeps failing, the belt was underspecified.
7. Tracking History
Ask maintenance how often they re-track this belt. A belt that is centered and then stays centered had a tension, alignment, or belt problem. All three problems are fixable. If a belt drifts back off center within days of every adjustment, the problem is usually structural. A warped or racked frame, or a frame on a settled leg, will never let a belt track. Chronic edge-rub on the frame confirms a structural cause. Edge-rub wears away belt edges fast.
8. Wear Liners, Bed Slats, and the Load Zone
The load zone wears the most and is the easiest part of the conveyor to rebuild. Abrasion-resistant plate is sacrificial. AR400 is graded by hardness, not by chemistry. Its hardness is typically 360 to 444 Brinell, which is why it is the normal liner choice for chutes, hoppers, and bins. A liner that has worn through to the steel behind it did its job. The question is whether that steel survived. The same is true of a Remcon slider bed conveyor. The bed is made of replaceable 3/8" flat-bar slats inside a formed 3/16" plate steel frame. The wearing surface can be renewed without touching the frame.
Repair or Replace: The Triggers
Compare your findings with this table. One replace-side finding on its own is worth a second look. If several replace-side findings are present together, especially in the frame, that is your answer.
| What you found | What it means | Verdict |
|---|---|---|
| Top cover worn through to the carcass | Belt at end of life; frame unaffected | Repair: new belt |
| Splice failing repeatedly in the same belt | Carcass around the splice is fatigued | Repair: new belt, not another splice |
| Bed slats or wear liners worn through | Sacrificial parts did their job | Repair: reline it |
| Bearings hot, noisy, or contaminated | Lubrication or sealing failure | Repair: bearings, seals, and the cause |
| One hairline crack at a single weld toe | Local stress riser | Repair: grind, re-weld, reinforce |
| Belt drifts off center within days, every time | Frame racked, twisted, or on a settled leg | Check the structure before the belt |
| Frame rusted thin at a pit line or splash zone | Section gone where it stays wettest | Replace the section, keep the conveyor |
| Cracks at multiple welds and load points | Structure repeatedly loaded past its design load | Replace |
| Permanent bow in a stringer, belt empty | Steel has yielded | Replace |
| Frame visibly flexes or pumps under load | Built too light for the material | Replace |
The Middle Answer: Replace the Section, Not the Conveyor
Conveyors rarely wear out evenly. The in-ground section rusts while the incline above stays in good condition. On a two-conveyor baler feed line, we found the in-ground portion of the first conveyor badly rusted. The in-ground portion had sat underwater for much of its life. Instead of replacing the first conveyor, we fabricated a new in-ground section in the shop. We fitted it to the existing above-ground portion on site. At the same time, both conveyors received new belts, drive components, and wear parts. The same method is also used to lengthen, re-angle, or move a conveyor. See system reconfiguration and moving.
What a Rebuild Should Include
If the frame passes, do the rebuild properly. Working components have improved over the last 10 to 20 years. A shutdown is the cheapest time to install the improved components. Examples are better bearings, a current gear reducer, and a more durable belt. Another example is a variable frequency drive (VFD) for soft start and jam protection instead of shear pins. Belt replacement and repair is usually the main job. The other work is scheduled around it.
A rebuild should also fix the cause, not the symptom. We look for the cause of the wear. We change the design so the wear does not come back. For example, we convert a solid bed to a slat bed, so dirt stops packing under the belt. We also remount a gear reducer so the drive line aligns.
Quotes to Be Careful With
You should be careful with two kinds of quotes. The first is a new-equipment quote written without anyone inspecting the existing frame. That vendor cannot know whether you need new equipment. The second is a rebuild quote priced only on the parts you pointed to. If nobody looked at the stringers, the weld toes, and the legs, the change order arrives after the conveyor is taken apart. Our guide on how to buy a conveyor lists the other questions to ask.
Remcon has built heavy-duty recycling equipment since 1977. We rebuild machinery that other manufacturers built as readily as machinery that we built. Send photos of the frame, the tail section, the load zone, the legs, and any cracking. Also tell us what the conveyor handles now and what it handled when it was installed. If the frame is sound, we will say so. We will quote wear parts instead of a new conveyor.
Repair or Replace a Conveyor FAQ
Should I repair or replace my conveyor?
If the frame is sound and the worn parts are wear parts, repair the conveyor. Wear parts include the belt, idlers, bed slats, liners, lagging, and bearings. Wear parts are consumables. Replacing them on a sound frame is cheap. If the frame itself is undersized or cracking at multiple load points, replace the conveyor. The reason is that no belt fixes a structure built too light for the load. The test is the frame, not the age of the conveyor.
My conveyor frame is cracked. Can it be repaired?
Whether the frame can be repaired depends on how many cracks there are and where they are. In welded steel structures, fatigue cracks typically start at weld toes, because weld toes are stress concentrations. One hairline crack at a single weld can be ground out, re-welded, and reinforced. Cracks at several welds and load points along the same frame mean the structure is being loaded past its design load. Repairing the cracks one at a time only changes where the next crack appears, a few feet down the run.
How do I know if my conveyor is worth rebuilding?
Check four things. While the conveyor runs loaded, watch whether the frame visibly flexes or pumps under a normal load. Then lock out the conveyor. Check three more things. Check whether any stringer holds a permanent bow when the belt is empty. Check whether the frame diagonals still match. Check whether cracks show at more than one weld or load point. If all four checks pass, the conveyor is worth rebuilding. If two or more checks fail, you are only delaying the need to replace the conveyor.
Is refurbishing a conveyor cheaper than buying new?
Refurbishing is often cheaper when the frame is sound. The reason is that you pay for wear parts and labor instead of a new structure. There is no fixed percentage rule that decides whether refurbishing costs less. Cost depends on how much steel is replaced and on how long the line can be down. Cost also depends on how much of the work happens on site and how much in the shop. We build to order. We quote repair and replacement per job.
How many times can a conveyor belt be spliced?
There is no fixed number, but the belt shows when it is at the end of its life. Every endless belt has at least one splice. A second splice from a field repair is common. When a belt keeps failing at or beside the splice, the carcass around the splice is fatigued. A new splice is made in the same fatigued material. In that case, replace the belt. Check that its PIW rating matches the tension the conveyor develops.
Why does my belt keep mistracking after every adjustment?
The cause is probably not the belt. A belt that drifts back off center within days of every adjustment usually has a structural cause. Structural causes are a racked or twisted frame, a settled leg, or a pulley that is no longer square to the conveyor centerline. Tracking adjustment treats the symptom, so the drift comes back. Measure the frame diagonals first. If the diagonals do not match, the frame is out of square. No belt adjustment will hold.