UV Curing Conveyor Systems for High-Volume Production
High-volume lines cannot afford a curing step that stops the flow. A UV curing conveyor moves parts continuously under one or more lamp heads at a regulated speed, so the cure keeps pace with dispensing and assembly instead of becoming the bottleneck. Configuring the Conveyor A conveyor system is defined by a handful of adjustable parameters: Belt width and length: Width accommodates the widest part or fixture; length sets how many lamp heads fit and how much dwell time is available. Lamp head count: One head for a single-pass cure, two or more for staged curing or to double the dose at speed. Adjustable lamp height: Raising or lowering the head, commonly over a range of about 40–125 mm, trims irradiance at the part surface and clears tall fixtures. Variable belt speed: A regulated drive spanning roughly 0.5–6 m/min sets the exposure time under each head. Choosing the Lamp Head The conveyor is a transport; the lamp head does the curing. Mercury arc heads emit a broadband spectrum, cure deep and pigmented sections well, and need exhaust for ozone. UV LED heads emit a narrow band at 365, 385, or 405 nm, run cool, switch instantly, and last far longer between replacements. A platform that accepts both, such as Incure's CDM UV conveyor, lets a line change lamp technology without replacing the whole system. Bench comparisons of F-Series arc lamps and L-Series LED lamps help size the head before it goes on the belt. Dose at Line Speed The UV dose a coating absorbs equals lamp irradiance in mW/cm² multiplied by the exposure time, and exposure time is the illuminated window length divided by belt speed. To hold dose constant when speeding the line up, either add a lamp head, lengthen the window, or raise irradiance by lowering the head. Verify the result with a band-matched radiometer riding through on the belt. Single Pass or Multiple Heads A single lamp head over a short window forces a slow belt to give the adhesive enough exposure. Adding a second head, or lengthening the illuminated zone, lets the belt run faster for the same total dose. The arithmetic is direct: two identical heads over a combined 300 mm window at 6 m/min deliver the same dose as one head over 150 mm at 3 m/min, at double the line rate. Staging can also help chemistry, with a lower-intensity first head to gel the surface and a full-intensity second head to complete the cure. Lamp Height and Irradiance Raising or lowering the head changes irradiance at the part surface. Lowering it boosts dose without slowing the belt, but reduces clearance for tall fixtures and can push a heat-sensitive part past its limit under an arc head. Set the height to the lowest position that still clears the tallest part with margin, then trim belt speed to fine-tune dose. Part Presentation Consistent results need consistent part orientation and spacing on the belt. Parts that tumble, overlap, or shadow each other receive uneven dose. Use…