How Do I Maintain Stackers and Runout Tables on a Roll Forming Line?

Learn how to maintain roll forming stackers and runout tables to prevent scratches, jams and misalignment.

Why Stacker & Runout Maintenance Matters

Poorly maintained handling systems cause:

• Surface scratching (especially pre-painted coil)

• Edge denting

• Panel bowing

• Stacker misalignment

• Product jams

• Inconsistent stacking

• Slow production

Even if the profile is perfect, poor handling ruins it.

1️⃣ Daily Cleaning (Most Important)

Metal dust and debris cause scratching and jams.

Daily:

✔ Clean runout rollers
✔ Remove metal shavings
✔ Wipe transfer belts
✔ Clear stacker tray
✔ Check drop zones

Pre-painted material requires extra cleanliness.

2️⃣ Inspect Rollers & Bearings

Runout tables rely on smooth rollers.

Weekly:

✔ Check roller rotation
✔ Inspect for flat spots
✔ Check bearing play
✔ Replace seized bearings
✔ Confirm alignment

Seized rollers drag panels and scratch coatings.

3️⃣ Maintain Roller Alignment

Misaligned rollers cause:

• Panel skewing

• Uneven stacking

• Side edge damage

Monthly:

✔ Verify straightness across table
✔ Check levelness
✔ Confirm side rails are square

Even small misalignment becomes visible on long panels.

4️⃣ Inspect Belt Conveyors (If Equipped)

If using belts:

✔ Check tension
✔ Inspect for wear
✔ Check tracking
✔ Replace frayed belts
✔ Ensure smooth speed control

Loose belts cause jerking and panel marking.

5️⃣ Check Stacker Lift Mechanism

Automatic stackers rely on:

• Hydraulic lift

• Chain drive

• Servo lift

Inspect weekly:

✔ Lift smoothness
✔ Cylinder leaks
✔ Chain tension
✔ Alignment of stack arms

Uneven lift causes stack tilt and product damage.

6️⃣ Monitor Drop Height

Excessive drop height causes:

• Panel deformation

• Edge damage

• Surface impact marks

Adjust:

✔ Stack height controls
✔ Lift synchronization
✔ Sensor positioning

Keep drop height minimal.

7️⃣ Inspect Sensors & Limit Switches

Stackers depend on accurate detection.

Weekly:

✔ Test photo-eyes
✔ Confirm limit switch function
✔ Check wiring
✔ Clean sensor lenses

Sensor failure causes mis-timed stacking.

8️⃣ Lubricate Moving Components

Lubricate:

✔ Chain drives
✔ Lift guides
✔ Bearings
✔ Pivot arms

Follow manufacturer interval (typically weekly to monthly).

Avoid over-greasing near panel contact areas.

9️⃣ Check Structural Stability

Vibration loosens:

✔ Frame bolts
✔ Guide rails
✔ Support brackets

Monthly torque check prevents alignment drift.

🔟 Prevent Surface Damage on Pre-Painted Coil

For coated materials:

✔ Use rubber-coated rollers
✔ Avoid sharp edges
✔ Replace worn polyurethane sleeves
✔ Keep all contact surfaces smooth

Handling damage is often mistaken for forming defects.

11️⃣ Maintain Proper Speed Synchronization

Stacker speed must match line speed.

If not synchronized:

• Panels collide

• Panels shift

• Stack becomes uneven

Verify speed matching regularly.

12️⃣ Monitor Panel Tracking

Watch for:

• Panel drifting sideways

• Uneven stacking

• End-of-line twisting

These often indicate roller misalignment.

Recommended Inspection Schedule

Daily (heavy production):

• Clean rollers and table

• Visual check of lift and sensors

Weekly:

• Inspect bearings

• Check alignment

• Lubricate moving parts

Monthly:

• Torque check

• Verify structural alignment

• Inspect belts and lift system

Quarterly:

• Full mechanical inspection

• Replace worn rollers

• Check hydraulic/servo calibration

Most Common Real-World Problems

1️⃣ Dirty rollers scratching pre-painted panels
2️⃣ Seized runout bearings causing drag
3️⃣ Uneven stacker lift causing panel tilt
4️⃣ Poor speed synchronization
5️⃣ Excessive drop height

Most issues are preventable with simple routine checks.

Final Expert Insight

To maintain stackers and runout tables:

✔ Clean daily
✔ Inspect rollers weekly
✔ Verify alignment monthly
✔ Lubricate moving parts properly
✔ Control drop height
✔ Maintain sensor accuracy
✔ Synchronize speed

The most common cause of finished panel damage is neglected runout rollers combined with poor cleaning discipline.

Stable handling protects:

• Product appearance

• Coating integrity

• Customer satisfaction

• Production efficiency

• Profit margins