Abstract: A system and method of cleaning a printing cylinder surface, wherein solid carbon dioxide is incorporated into an air stream, through a nozzle, and impinged on the printing cylinder surface. An exhaust tube may be present to evacuate materials removed by impacting the solid carbon dioxide on the printing cylinder surface. The nozzle and exhaust tube may be reciprocated over the printing cylinder surface to enable a more thorough and efficient cleaning operation. A sensor and control unit may be optionally present. The sensor would sense the thickness of a film being cumulatively deposited on the printing cylinder surface and generate a signal when the film reached a predetermined thickness. The control unit would initiate the cleaning operation in response to the signal from the sensor.

Abstract: A system and method of cleaning a printing cylinder surface, wherein solid carbon dioxide is incorporated into an air stream, through a nozzle, and impinged on the printing cylinder surface. An exhaust tube may be present to evacuate materials removed by impacting the solid carbon dioxide on the printing cylinder surface. The nozzle and exhaust tube may be reciprocated over the printing cylinder surface to enable a more thorough and efficient cleaning operation. A sensor and control unit may be optionally present. The sensor would sense the thickness of a film being cumulatively deposited on the printing cylinder surface and generate a signal when the film reached a predetermined thickness. The control unit would initiate the cleaning operation in response to the signal from the sensor.

Abstract: A cooling system for a sheet-fed printing unit, including at least one fan and a cooling element such as a chilled water coil. The printing unit includes a plurality of ink cylinders, a blanket cylinder, an impression cylinder, and one or more transfer cylinders. A source directs radiant energy onto substrate being printed to cure ink thereon. The radiant energy may be directed at substrates on the impression or transfer cylinders. In response to the radiant energy, the impression or transfer cylinders become heated and transfer heat to the substrate, which distorts as a result. The fan generates an airflow toward an impression or transfer cylinder. The airflow is within a predetermined temperature range and of a sufficient magnitude to maintain the impression or transfer cylinder within a critical temperature range to prevent or minimize substrate distortion.