In a batch system, parts are hung on carts, pushed into a booth for coating and then into an oven for curing. In a conveyorized line, an overhead conveyor carries parts continuously through pretreatment, booth, oven and cooling.
Batch vs conveyorized
| Criteria | Batch system | Conveyorized line |
|---|---|---|
| Output | Low to medium, limited by cart cycles | Medium to high, continuous |
| Labour | Operators move carts between steps | Operators load and unload only |
| Quality consistency | Depends on operator timing | Fixed speed and dwell times |
| Part variety | Very flexible, large parts | Best with recurring part families |
| Floor space | Compact for small volumes | Larger, but floor under conveyor usable |
| Investment | Lower | Higher |
When to move to a conveyor
- Carts wait for the oven or booth most of the day
- Labour for moving carts is a large share of cost
- Customers ask for more consistent film thickness and cure
- Volumes of recurring parts justify continuous running
- Pretreatment needs to be automated
Worked example: output comparison
A batch oven cures one cart of 40 panels every 30 minutes, about 80 panels per hour at best, and less when carts wait. A conveyorized line at 1.2 m/min with 2 panels per metre coats 144 panels per hour continuously, with two operators loading and unloading instead of a team moving carts.
Hybrid options
A conveyor can be added in stages: first an overhead loop between booth and oven, then automatic pretreatment. Batch ovens can sometimes be converted with a conveyor passing through. See powder coating line layout.
Questions to ask your supplier
- What output does the proposed line reach with our real parts?
- How many operators will the line need?
- Can existing booths or ovens be reused?
- How will large or one-off parts be handled?
Common mistakes to avoid
- Buying a conveyor line before volumes justify continuous running
- Choosing line speed without checking booth and oven capacity
- No space for loading, unloading and staging
- Forgetting how very large or one-off parts will still be coated
Decision checklist
| Question | Points to a conveyor if |
|---|---|
| Daily output | Batch equipment runs at its limit |
| Labour | Several people move carts all day |
| Part mix | Most parts are recurring families |
| Quality | Customers demand consistent film and cure |
| Space | Floor under an overhead loop can be used |
