Live steam is employed in setting the ink used in the printing of customer's names, emblems, and various other information on Kraft paper bags. It is necessary that steam be used as the bags must contain a certain amount of moisture for proper strength and quality. Ordinary steam however, resulted in excessive moisture and at times allowed water droplets to reach the bags.
For each of two large printing presses, a 9 kW Chromalox type GCH Steam Superheater is mounted on the press to superheat the steam to 350° F. The steam then flows from an applicator onto the paper, setting the ink, but allowing the paper to retain the proper amount of moisture.
The applicator pipes are kept hot (370° F) by Chromalox tubular heating elements that are clamped to the pipes. Heat loss was further reduced by installing an insulated hood over the applicator pipe assembly. Steam is available at the machine at all times. When the printing press is started, steam is available at the push of a button, which activates a solenoid valve.
- Excessive moisture or water no longer reaches the paper.
- Paper quality has been increased.
- Spoilage has been drastically reduced.
- Inexpensive, simplified installation of packaged steam superheater.