What are the commonly used conveyor lines in factories?
Automotive, logistics, appliance and paint plants each rely on three proven conveyors. Cars use power-and-free or ring-guided skids for 0.5-2 t bodies with ±2 mm accuracy. High-speed roller lines with pop-up wheel sorters move 6-8 k cartons per hour in modern DCs. Appliance assembly favours twin-deck speed-chain or triple-belt loops that return empty fixtures on-line and cut floor space 40%. Paint shops suspend bodies on overhead power-and-free chains and carry them through 180 °C ovens on high-temp mesh belts. Select by weight, environment and takt: <60 kg belt, 60-250 kg roller, >400 kg chain; wash-down 304 SS, explosion-proof Ex d IIB T4, continuous >6 k/h pop-up sorter.
I. One-sentence summary
- Automotive: “heavy + accurate” – power-and-free, skid & ring-guide dominate.
- Logistics & DC: “fast + space-saving” – high-speed roller + pop-up wheel sorter + vertical lift are the golden trio.
- Home-appliance assembly: “flexible + footprint” – twin-deck speed-chain + triple-belt loop give the best takt.
- Paint shop: “clean + heat” – overhead power-and-free, reverse skid & high-temp mesh belt are standard.
II. Master table (pick the class first)
| Plant type | Top-3 conveyors | 2025 China adoption | One-line benefit | Typical load / takt | Fresh case |
|---|---|---|---|---|---|
| Automotive | 1. Power-and-free (APC) 2. Skid + ring-guide 3. Heavy-duty skid & roller bed | 85 % of new lines | 0.5–2 t, ±0.1 mm, mixed-model | 45–60 s / car body | Geely Changxing BIW line |
| Logistics | 1. High-speed roller + pop-up sorter 2. Chain-driven roller + lift-transfer 3. Multi-tier shuttle + vertical lift | 100 % e-commerce / pharma / cold-chain | 6–8 k totes/h, 50 % floor saved | 30 kg tote / 1,200 pallets/h | East-China e-warehouse 100 k orders/day |
| Home appliance | 1. Twin-deck speed-chain 2. Triple-belt loop line 3. Overhead chain + pallet | 90 % AC / fridge / washer | Empty pallet returns on-line, 40 % floor saved | 30 kg / 20–30 s | Changzhou parts 3-tier loop |
| Paint shop | 1. Overhead power-and-free 2. Reverse power-and-free (inverted skid) 3. High-temp mesh belt | 100 % car body / parts | 360° rotate, 180 °C oven | 500 kg body / 30 s | New-energy OEM top-coat line |
III. Sub-tables (equipment-level data)
- Automotive (BIW + trim + chassis)
| Sub-process | Recommended conveyor | Load / accuracy | Speed / takt | 2025 mainstream spec | Watch-outs |
|---|---|---|---|---|---|
| BIW welding | Ring-guide + chain | 0.5–2 t / ±0.05 mm | 0.5–1.2 m/min, 45–60 s | Fixture with locating pin + secondary lift | Joint gap ≤2 mm or robot alarms |
| Seat / battery marriage | Heavy-duty speed-chain 12B | 300–400 kg / pallet | 3–20 m/min, 20–30 s | Pallet rotate + lift 200 mm | Quenched chain after 150 °C oven |
| Trim line | Triple-belt loop | ≤30 kg / fixture | 1.2–1.5 m/s | Top deck returns empties, middle buffers | Add damping rollers on idle middle deck |
| Chassis line | Skid / roller bed | 1–2 t / ±5 mm | VFD 0–10 m/min | Lift 400 mm + on-board power | Check guide rollers monthly |
- Logistics & DC (receiving → sorting → shipping)
| Sub-process | Conveyor | Cart / pallet spec | Peak rate | 2025 mainstream spec | Watch-outs |
|---|---|---|---|---|---|
| Carton inbound | High-speed roller + pop-up wheel | 600×400×400 mm, ≤50 kg | 6–8 k totes/h | Pop-up 6 k/h, belt 2.5 m/s | Roller pitch = ⅓ carton length |
| Pallet in/out | Chain-driven roller + lift-transfer | 1,200×1,000 mm, 1 t | 120–150 pallets/h | Twin-chain + servo centring | Low-temp bearing -30 °C grease |
| Multi-tier buffer | Shuttle + vertical lift | 80 kg tote | 2–3 tier loop | Lift 12–18 m/min | Hand-off tolerance ≤2 mm or jam |
| Bulk grain / fertiliser | Oil-resistant EP400 belt | 50–100 t/h | 1.6–2 m/s | Fully enclosed + dust hood | Max incline 18°, add cleats above |
- Home-appliance assembly (AC / fridge / washer)
| Sub-process | Conveyor | Part wt / size | Takt | 2025 mainstream spec | Watch-outs |
|---|---|---|---|---|---|
| Main assembly | Twin-deck speed-chain | 20–30 kg | 25–35 s | Top deck returns empties, bottom assembles | D/d ratio 2–2.5, wear <0.3 mm |
| Vacuum & QC | Overhead chain + pallet | 15 kg | 30 s | Pallet 360° rotate | Lube chain monthly or noisy |
| E-test | Triple-belt loop | 5 kg | 1.5 m/s | Middle deck tests, others buffer | 2 mm conductive PU belt anti-static |
| Packing exit | Flexible plastic-chain | ≤10 kg | 40 m/min | Side-flex R150 mm | Tension screw must work “in compression” |
- Paint shop (pretreatment → spray → oven)
| Sub-process | Conveyor | Load / temp | Speed | 2025 mainstream spec | Watch-outs |
|---|---|---|---|---|---|
| Pretreatment / ED | Overhead power-and-free | 500 kg body, RT-50 °C | 0.5–2 m/min | 450 mm pitch, can stop & disconnect | Tension check every 6 months |
| Spray booth | Reverse power-and-free (inverted skid) | Same, 23 °C constant | 1–1.5 m/min | Skid with bushings, robot repeat ±0.2 mm | Ex d IIB T4 motors in zone 1 |
| Oven 180 °C | High-temp mesh belt | Same, peak 200 °C | 0.8 m/min | 316L belt + ceramic-fiber curtain | Belt stretch 2-3 %, too loose = drift |
| Floor return | Roller + lift-cross transfer | Empty skid 80 kg | 12 m/min | Lift 40 mm, twin-chain drive | Add hydraulic buffer to cut noise |
IV. Quick-selection cheat sheet (memorise & decide in 10 min)
- Weight first
≤60 kg → belt / plastic-chain
60–250 kg → roller / speed-chain
≥400 kg → power-and-free / ring-guide - Environment next
>150 °C → mesh belt + ceramic curtain
Wash-down / clean-room → 304 SS + IP65
Explosion-proof → Ex d IIB T4 motor - Takt last
Continuous >6,000 pcs/h → pop-up sorter + high-speed roller
Asynchronous accumulate → speed-chain / power-and-free
Accuracy ±0.1 mm → ring-guide + locating pin
Paste the above “text + master table + sub-tables” into your project book and you can lock the main conveyor concept for any of the four plants within 10 minutes; handle remaining special cases (explosion-proof, strong acid, >600 °C) in a separate non-standard study.