varying from 1.0 to 5.0 mm 0.020 to 0.190 inch and shall have an
automatic drop-on bead system. The mobile unit shall be capable of
operating continuously and of installing a minimum of 6 km 20,000
lineal feet of longitudinal markings in an 8-hour day.
(1) The mobile unit shall be equipped with a melting kettle which
holds a minimum of 2.7 metric tons 6000 pounds of molten
thermoplastic material. The kettle shall be capable of heating
the thermoplastic composition to temperatures of 195 to 220
degrees C 375 to 425 degrees F. A thermostatically controlled
heat transfer liquid shall be used. Heating of the composition by
direct flame will not be allowed. Oil and material temperature
gauges shall be visible at both ends of the kettle. [The mobile
unit shall be equipped with a minimum of two extrusion shoes
located one on each side of the truck, and shall be capable of
marking simultaneous edgeline and centerline stripes. Each
extrusion shoe shall be a closed, oil-jacketed unit; shall hold
the molten thermoplastic at a temperature of 195 to 220 degrees C
375 to 425 degrees F; and shall be capable of extruding a line of
75 to 200 mm 3 to 8 inches in width; and at a thickness of not
less than 3 mm 0.125 inch nor more than 5.0 mm 0.190 inch, and of
generally uniform cross section.] [The mobile unit shall be
equipped with a spray gun system. The spray system shall consist
of a minimum of four spray guns, located two on each side of the
truck, and shall be capable of marking simultaneous edgeline and
centerline stripes. The spray system shall be surrounded
(jacketed) with heating oil to maintain the molten thermoplastic
at a temperature of 195 to 220 degrees C 375 to 425 degrees F; and
shall be capable of spraying a stripe of 75 to 300 mm 3 to 12
inches in width, and in thicknesses varying from 1.5 mm 0.055 inch
to 2.5 mm 0.095 inch, and of generally uniform cross section.]
(2) The mobile unit shall be equipped with an electronic
programmable line pattern control system. The control system
shall be capable of applying skip or solid lines in any sequence,
through any and all of the extrusion shoes, or the spray guns, and
in programmable cycle lengths. In addition, the mobile unit shall
be equipped with an automatic counting mechanism capable of
recording the number of lineal meters feet of thermoplastic
markings applied to the pavement surface with an accuracy of 0.5
percent.
b. Portable Application Equipment: The portable applicator shall be
defined as hand-operated equipment, specifically designed for placing
special markings such as crosswalks, stopbars, legends, arrows, and
short lengths of lane, edge and centerlines. The portable applicator
shall be capable of applying thermoplastic pavement markings by the
extrusion method. The portable applicator shall be loaded with hot
thermoplastic composition from the melting kettles on the mobile
applicator. The portable applicator shall be equipped with all the
necessary components, including a materials storage reservoir, bead
dispenser, extrusion shoe, and heating accessories, so as to be capable
of holding the molten thermoplastic at a temperature of 195 to 220
degrees C 375 to 425 degrees F, of extruding a line of 75 to 300 mm 3
to 12 inches in width, and in thicknesses of not less than 3.0 mm 0.125
inch nor more than 5.0 mm 0.190 inch and of generally uniform cross
section.
SECTION 02763A
Page 9
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