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Crosswalks, stop bars, turn arrows, and lettering ("ONLYs") increasingly have become targets for the more-expensive but longer-lasting thermoplastic markings, so many contractors are considering adding this service to their pavement marking operations.

Thermoplastic, as applied to pavement, is a molten material created from melting either plastic granules or a pre-mixed material that is heated, cooled, and formed into a block which is then melted. Material is heated to 400°F - 425°F before it is applied to the pavement by a walk-behind thermoplastic handliner.

Handliners are smaller, portable pieces of equipment that hold the molten material and maintain it at the proper temperature long enough to let the operator apply it to the pavement. Made of either steel or aluminum, handliners are pushed by the operator - none are self propelled.

Each handliner features a tank to hold the molten plastic, a manual agitator to enable the operator to keep the material mixed, and a propane-fueled burner beneath the holding tank and on the side of it that heats the die that accept the molten material from the tank and form it into shape on the pavement.

Melting capability
Manufacturers agree that the most effective way to heat the material is in a kettle - separate pieces of equipment attached to a stake truck or trailer. Heated by either diesel or propane, the kettles are designed to heat the granules or blocks in large amounts and to maintain the material at a specific temperature while the crew is placing markings. The operator pushes the handliner to the trailer, gravity flow fills the handliner tank with the molten material from the kettle, and the operator returns to marking the pavement.