Dynamic Supply Knowledge Series · Volume 4 · Chapter 7
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What a Conveyor Dryer Does
A conveyor dryer moves printed garments through a heated chamber at a controlled belt speed. Its purpose is to deliver the time and heat needed for the ink system to reach the manufacturer’s specified cure conditions.
Flash vs. Final Cure
Flash curing temporarily gels ink between print colors. Final curing must develop the ink’s required durability. A print that feels dry is not necessarily fully cured.
- Print: deposit ink.
- Dryer: heat and dwell.
- Verify: confirm cure.
The Three Variables
Ink chemistry, actual ink-film temperature, and time at the required temperature determine cure. Dryer display temperature alone does not prove that the ink has cured.
Important Consideration
Cure requirements vary among plastisol, water-based, discharge, and specialty ink systems. Always follow the specific ink manufacturer’s technical data sheet and equipment safety instructions.
Main Components
A typical dryer includes an infeed belt, a heated chamber, temperature controls, airflow or exhaust provisions, and an outfeed section. Configuration varies by manufacturer and dryer model.
Garments travel from the infeed through the heated chamber, where heat and airflow or radiant energy act on the print, then to the outfeed.
Belt Speed and Dwell Time
A slower belt generally increases time in the heated chamber; a faster belt reduces it. Changes to belt speed can also affect production throughput and garment exposure to heat.
When a Dryer Is Too Short
A short heated chamber may not provide sufficient dwell time at the desired belt speed. Operators may need to slow the belt or make additional passes to achieve the ink manufacturer’s cure requirements. Extra passes increase handling, reduce throughput, and may create inconsistent heating or overexposure. A properly sized dryer should achieve verified cure in one controlled pass under normal production conditions.
Heat Distribution
Airflow, heating method, garment loading, ink coverage, and belt position can affect actual cure. Test the complete print under normal production conditions, not only an empty dryer.
Match the Dryer to Your Production
Consider the ink systems used, expected garments per hour, print dimensions, belt width, chamber length, electrical or gas requirements, ventilation, available floor space, and room for growth.
How to Verify Cure
Follow the ink manufacturer’s curing instructions. A temperature probe can help check conditions, but temperature readings alone do not confirm a full cure. Perform the recommended wash and durability tests to verify finished-print performance.
Common Production Problems
Under-curing can cause cracking, poor wash durability, and weak adhesion. Over-curing can also contribute to cracking or brittleness in some ink systems, as well as scorching, discoloration, or fabric damage. Uneven heating can produce inconsistent results across a run. Diagnose the cause with ink-specific cure testing rather than relying on appearance alone.
Before You Invest
- Which inks and garment materials will we cure?
- What production volume and largest print size must the dryer handle?
- What electrical, gas, exhaust, and clearance requirements apply?
- How will we measure and document consistent cure?
- Can the dryer keep pace with the printing press in a single verified pass?
Dynamic Insight
A dryer becomes a production bottleneck when its verified single-pass cure capacity falls below press output. Select chamber length and heating capacity together, not belt width alone.
Choosing a Heat Source
Both electric and gas conveyor dryers can achieve reliable final curing when correctly sized and operated. The right choice depends on ink chemistry, production volume, utilities, ventilation, and operating costs.
Electric Conveyor Dryers
An electric dryer uses electrical heating elements, often with infrared heat and/or forced air. Electric equipment may be practical for smaller shops or facilities without gas service. Confirm available voltage, phase, amperage, and operating costs.
Gas Conveyor Dryers
A gas dryer uses natural gas or propane for heat, typically paired with controlled airflow. A properly designed gas dryer is often well suited to high-volume water-based printing, where efficient moisture removal is essential. Confirm fuel supply, combustion air, exhaust, permits, and installation costs.
Compare Complete Dryer Performance
Fuel type alone does not guarantee curing performance. Compare heated chamber length, airflow, moisture removal, temperature uniformity, verified throughput, and total operating costs. A properly sized electric dryer with sufficient airflow can also cure water-based inks successfully.
Installation and Safety
Follow the manufacturer’s clearance, ventilation, and electrical requirements. Gas-fired systems also require appropriate fuel connections, combustion-air provisions, and exhaust arrangements. Use qualified installers and comply with applicable codes.
Water-Based Ink Production
Water Must Evaporate First
Unlike plastisol inks, water-based inks contain water that must be driven off during drying. After sufficient moisture removal, the ink must still reach the manufacturer’s specified curing conditions to develop durability. A dry-looking print is not proof of complete cure.
Why Airflow Matters
Heated airflow helps carry evaporated moisture away from the print and dryer chamber. Without adequate airflow and exhaust, evaporation can be slow or uneven. Heat alone is not the whole answer: chamber length, airflow, belt speed, ink deposit, and garment loading all matter.
When a Dryer Is Too Short for Water-Based Production
A short dryer may not provide enough time to evaporate water and complete the cure at a normal production belt speed. Operators may need to slow the belt significantly or send garments through multiple passes. Several passes add labor and handling, restrict throughput, and can create inconsistent heating. Verify cure using the ink manufacturer’s recommended method.
Why Gas Is Often Preferred
For sustained, higher-volume water-based production, a properly engineered gas conveyor dryer often offers an effective combination of heating capacity and forced airflow. However, gas is not automatically superior; an electric dryer designed with adequate airflow, chamber length, and capacity may also perform well.
Buy for the Ink System You Will Run
Ask the dryer manufacturer to demonstrate verified single-pass curing at your intended belt speed, garment loading, and water-based ink coverage. Include room for future production growth rather than sizing only for today’s plastisol output.
Anatol Dryer Examples
Anatol Solutions: Electric
Ceramic heating elements; configurable heat-chamber lengths.
Anatol Ultra: Electric
Forced-air circulation supports water-based and plastisol curing.
Anatol Vulcan: Gas
Gas-fired dryer with chamber air circulation and exhaust.
Conveyor Dryer Components and Dimensions
Heat Chamber Length Matters
Overall length combines infeed, heated chamber and outfeed. At the same belt speed, a longer heated chamber provides more time under heat. Infeed and outfeed provide loading and unloading space; they do not extend heated dwell time.
A short chamber may require a slower belt or additional passes, particularly for water-based inks. This is an illustrative diagram, not to scale. Confirm dimensions for the exact dryer model.
Maintenance and Safety
Regular cleaning and inspection help maintain consistent curing, reduce downtime, and limit fire and equipment hazards. Always follow the maintenance schedule for the specific dryer model.
Daily
Inspect the belt for lint, debris, ink deposits, damage, and smooth tracking. Keep infeed and outfeed clear. Follow the manufacturer’s prescribed shutdown and cool-down procedure.
Weekly
Clean accessible belt surfaces using approved methods. Check ventilation openings for lint accumulation. Listen for unusual blower, motor, and roller noise.
Periodic
Inspect exhaust ducting, airflow, filters, belts, rollers, controls, and safety devices at the intervals specified in the equipment manual. Have qualified personnel inspect electrical and gas systems as required.
Gas Dryer Considerations
Burner, combustion-air, gas-line, and exhaust-system work should be performed by qualified technicians. Maintain required ventilation and clearances.
Electric Dryer Considerations
Have qualified personnel inspect heating elements, wiring, connections, and controls. Never open electrical enclosures or service energized components.
Safety First
Allow the dryer to cool fully before cleaning. Disconnect or isolate energy sources as directed by the manufacturer before servicing. Lint buildup near heat and exhaust systems can create a fire hazard. Never bypass guards or safety controls.
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