Troubleshooting Common Issues in Powder-Coating Lines

Addressing  Tehran Poshesh  necessitates a structured process to locate the source of issues and enforce correct fixes

Poor adhesion is one of the top issues, typically resulting from improper part prep

It is essential to cleanse all substrates completely of grease, rust, dirt, and any other surface pollutants

Inadequate cleaning duration or polluted bath solutions prevent proper powder bonding

Consistently check cleaning fluid quality and maintain optimal rinse and drying conditions to avoid spotting or film residues

Irregular powder layer distribution is also frequently observed

This can result from improper gun settings, such as incorrect voltage or amperage, or from parts being too close or too far from the spray nozzle

Proper operator technique includes holding a fixed gap—commonly 6–12 inches—and using continuous, flowing motion across the surface

Uncontrolled air movement in the spray zone affects powder deposition—install dedicated exhaust and block external drafts

Blockages in the powder feed mechanism are also commonly encountered

This usually occurs when powder absorbs moisture due to high humidity or improper storage

Always store powder in a climate controlled environment with humidity below 50 percent

Inspect hoses, filters, and fluidizing beds regularly for blockages, and clean them according to the manufacturer’s schedule

Any sign of agglomeration indicates compromised powder quality and requires disposal

Bumpy surface appearance commonly results from underbaking or deviations from the manufacturer’s recommended cure profile

Confirm the oven setpoint aligns with the supplier’s technical data and ensure components spend the full duration at cure temperature

The critical measurement is the part’s surface temp—use contactless thermometry to ensure accuracy

Excessive curing may lead to discoloration, brittleness, or loss of flexibility, making precise timing essential

Powder recovery system inefficiency leads to wasted material and increased costs

The recovery unit must be airtight, and its filters must be maintained on a strict cleaning or replacement schedule

Uneven air distribution impairs capture efficiency—inspect blower RPM and ductwork for leaks or obstructions

Keep recovery hoppers strictly segregated by color to prevent color-mixing defects

Electrostatic issues can cause powder to repel from the part or cling inconsistently

Confirm grounding continuity across racks and components using a low-resistance ohmmeter

Corroded or loose grounding connectors break conductivity—clean and replace them on a regular basis

When grounding checks out, investigate the HV generator and rectifier for output variance or component degradation

Finally, color inconsistencies across batches may arise from variations in powder formulation, incorrect flow rates, or mixing different lots

For each production run, source powder from a single lot and document its identification number

Transition between colors requires a full system cleanup to eliminate residual powder from prior formulations

Training staff to recognize early signs of these issues—such as irregular spray patterns or visual defects on test panels—can reduce downtime and improve overall quality

Regular preventive maintenance, operator training, and consistent documentation of process parameters are key to minimizing disruptions in powder coating operations

Proactively managing these issues enables plants to deliver long-lasting, superior finishes with optimal throughput and minimal material loss