Preventive Maintenance Guide

Why Preventive Maintenance is Critical
Preventive maintenance not only ensures the longevity of your conveyor system but also helps in avoiding costly downtime due to unexpected breakdowns. By following a regular maintenance schedule, you can keep your conveyor running smoothly and reduce the risk of accidents or equipment failure.

Maintenance Intervals
Routine checks should be performed according to the following schedule:

• Monthly Maintenance: For most preventive tasks like inspecting chain slack and wearstrips.
• Bi-weekly (Every 15 Days): For lubrication checks and wearstrip lubrication.
• Before Operation: Always run a checklist before starting the conveyor.

Environmental Contamination Inspection

Frequency: Monthly
Objective: Ensure the conveyor is free from environmental debris that could cause damage.

Common Contaminants:

• Abrasive Materials: Dust, metal chips, glass particles, etc.
• Construction Debris: Concrete dust, wood chips, ceramic dust from nearby work areas.
• Product Residue: Sugar, flour, or other food particles.

Steps:

1. Inspect the top and bottom of wearstrips for debris.
2. Wipe down all surfaces with a cloth dampened with rubbing alcohol or water.
3. If contamination is severe, remove the conveyor chain for deeper cleaning.
4. Cover the conveyor during nearby construction to prevent debris from settling on it.

Note: Operating a conveyor with environmental contamination can lead to increased friction, overheating, and chain derailment.

Chain and Wearstrip Inspection

Frequency: Monthly
Objective: Check for broken or worn chain links and proper wearstrip installation.

What to Look For:

• Chain Links: Broken links, worn foot tabs, and loose or missing lock tabs.
• Wearstrips: Proper fit, no overlaps, cut at the right angle to match the chain flow direction.

Steps:

1. Examine the chain for visible cracks or broken links. Replace any damaged links.
2. Inspect the wearstrip for signs of overheating or excessive wear. Make sure the wearstrip is properly seated on the conveyor frame.
3. Check the wearstrip gap (temperature-dependent) to ensure there’s no overlap that could cause chain derailment.
4. Verify that all chain lock tabs are snapped securely into place.

Common Issues:

• Problem: Chain derailment due to worn wearstrips.
• Solution: Replace damaged wearstrips and ensure proper installation.
• Problem: Broken lock tabs lead to chain instability.
• Solution: Replace or re-secure lock tabs immediately.

Drive/Idler Wearstrip Inspection

Frequency: Monthly
Objective: Ensure the wearstrips on drive and idler units (horseshoes) are in good condition.

What to Inspect:

• Horseshoes: These curved wearstrips guide the chain around the drive and idler units.
• Side Plates: Check for damage or excessive wear.

Steps:

1. Verify that the wearstrips are securely fitted around the drive and idler side plates.
2. Ensure that the wearstrips are pinned correctly and are not disengaged from the side plates.
3. Inspect for loose or missing fasteners in the drive and idler units.
4. Replace any worn or damaged wearstrips immediately.

Foreign Object Interference Inspection

Frequency: Monthly
Objective: Ensure there are no foreign objects obstructing the chain or conveyor system.

Common Foreign Objects:

• Loose tools, bolts, debris from adjacent machinery, or product spillover.
• Objects interfering with chain movement at loading or unloading points.

Steps:

1. Inspect the entire length of the conveyor for foreign objects that may be obstructing chain movement.
2. Ensure that transfer plates, fingers, and other components are clear of the conveyor chain.
3. Adjust guide rails, brackets, and raised side walls if they are making contact with the chain.
4. Remove any tools, bolts, or debris from the conveyor area.

Tip: Keeping the conveyor area clean and free of debris helps prevent sudden equipment failure and increases conveyor lifespan.

Chain Slack and Sprocket Engagement Inspection

Frequency: Monthly
Objective: Adjust chain slack and ensure proper engagement with sprockets.

Why It’s Important:

• Too Much Slack: Can cause the chain to jump the sprocket teeth, resulting in motor strain and increased wear.
• Too Little Slack: Creates excessive tension, causing the chain to wear out prematurely.

Steps:

1. Measure the amount of slack by compressing three rows of links with your thumb and forefinger. If you can’t compress three rows, the chain is too tight; if you can compress more than three rows, it’s too loose.
2. Adjust slack by removing or adding rows of links until the slack is within acceptable limits.
3. Inspect sprockets to ensure they are properly engaging with the chain links. The sprocket teeth should align with the chain, particularly just behind a connecting rod.
4. Monitor for excessive chain slack after the drive sprockets to prevent jumping.

Lubrication and Lubricator Inspection

Frequency: Every 15 Days
Objective: Ensure the wearstrips are properly lubricated to reduce friction and prevent wear.

Systems with Lubricators:

• Steps:
1. Check the fill level of the lubricator reservoir.
2. Verify that the wearstrip lubricators are properly adjusted to apply sufficient lubrication to the wearstrips.

Systems without Lubricators:

• Manual Lubrication:
1. Use SpanLube silicone oil and apply it directly to the area where the conveyor chain and wearstrip meet on the bottom side of the conveyor.
2. Avoid using too much lubricant as it can attract contaminants.

Warning: Avoid using lubricants that could contaminate the product being conveyed. Silicone oil is difficult to remove once applied, so use it cautiously if contamination is a concern.

Motor Current Measurement

Frequency: Monthly
Objective: Measure motor amperage to ensure it’s within acceptable levels and detect any system strain.

What to Check:

• Motor amperage readings should be compared against the values provided on the motor’s specification plate.

Steps:

1. Use a clamp-on multimeter to measure the running amperage for each of the motor’s three power leads (excluding the ground lead).
2. Compare the readings to the specified values on the motor plate.
3. If the measured values exceed the specified range, investigate for possible issues such as excessive chain slack, poor sprocket engagement, or contamination.

Tip: Keep a log of all motor current measurements. Sudden increases in amperage could indicate a mechanical issue requiring immediate attention.

Preventive Maintenance Checklist 

• Monthly: Chain and wearstrip inspection, foreign object inspection, drive/idler inspection.
• Every 15 Days: Lubrication check.
• Ongoing: Monitor motor current and chain slack.

Preventive Maintenance Checklist

Preventive maintenance is essential to keeping your conveyor system running efficiently. Below, you’ll find a comprehensive checklist that can be followed on a daily, weekly, and monthly basis to maintain your conveyor system in peak condition.

Daily Maintenance Checklist

For daily operations, a quick visual inspection can help prevent small problems from escalating into larger issues.

• Inspect Conveyor Area: Make sure there are no foreign objects (tools, debris, etc.) in the path of the conveyor.
• Check Emergency Stop Buttons: Ensure all emergency stops are functioning and accessible.
• Visual Inspection of Chain: Look for obvious damage like broken links or excessive slack.
• Verify Lubrication (if applicable): Ensure that automatic lubricators are functioning and filled with lubricant.
• Conveyor Load: Confirm the system is operating within its specified load limits.

Weekly Maintenance Checklist

A more detailed weekly inspection will help identify wear and tear on components and ensure proper lubrication.

• Inspect Chain Tension: Compress three rows of chain links to check for proper tension. Adjust slack as necessary by adding or removing links.
• Lubrication Check: Manually lubricate wearstrips (if no automatic system is present) using SpanLube silicone oil or another approved lubricant.
• Wearstrip Condition: Check for signs of wear, overheating, or misalignment in the wearstrips.
• Clean Wearstrips: Wipe down wearstrips to remove debris or residue buildup.

Monthly Maintenance Checklist

This more thorough monthly check should involve system shutdown and inspection of key components.

1. Chain and Wearstrip Inspection

• Inspect Chain for Damage: Look for broken links, bent rods, or loose lock tabs. Replace any damaged components immediately.
• Check for Chain Elongation: Measure chain elongation and replace the chain if the elongation exceeds 4% (MonoSpan and MultiSpan) or 2% (MaxiSpan).
• Wearstrip Installation: Ensure wearstrips are correctly seated, with no overlaps or gaps wider than 1/4″. Replace any worn or damaged strips.

2. Motor and Drive System Check

• Measure Motor Current: Use a clamp-on meter to check the motor’s current draw and compare it to the motor’s specification plate.
• Check Gearmotor Oil Levels: For systems with gearmotors, ensure oil levels are sufficient and refill as necessary.
• Inspect Drive Sprockets: Check for worn or damaged sprockets. Ensure sprockets are aligned and engaging correctly with the chain.

3. Foreign Object and Safety Inspection

• Clear Any Debris: Inspect the entire conveyor for loose bolts, tools, or foreign objects that could interfere with the chain.
• Safety Guard Check: Ensure that all safety guards and labels are in place and in good condition.

Bi-Annual Maintenance Checklist

Twice a year, it’s important to perform a deep inspection of the system.

• Full System Inspection: Shut down the conveyor for a complete inspection of all components, including chain tension, wearstrips, sprockets, gearmotors, and the electrical system.
• Replace High-Wear Parts: Check high-friction areas and replace components such as wearstrips and chain links that show signs of wear.
• Chain Realignment: Ensure chain and sprockets are properly aligned and free from obstructions or uneven wear.