Radiography in Modern Industry - Kodak

Processing TanksProcessing the films, which involves the wet activities of developing, stopping, fixing, andwashing, should be carried out in an area separate from the loading bench. This arrangement isdesigned to avoid splashing solutions on screens, films, and loading areas and, in general, toprevent interference with loading-bench operations.The tanks must be constructed of a corrosion-resistant material. The majority are now beingfabricated of AISI Type 316 stainless steel with 2 to 3 percent of molybdenum. Special techniquesmust be employed in the fabrication of these tanks to avoid corrosion in the welded areas.The film capacity of the entire processing area is determined by the size of the insert tanks.Based on a 5-minute development time, a 5-gallon developer tank can handle 40 films an hourwith four hangers being handled simultaneously, and allowing for the time during which thehangers are removed and inserted in the stop bath. The capacity of the stop bath tank should beequal to that of the developer tank, and the fixer tank should be at least twice as large as thedeveloper tank. The washing tank should hold at least four times the number of hangersaccommodated in the developer tank.Film DryersOne of the important considerations in designing the processing area is the film dryer. It shouldbe fast-acting without overheating the film. Hot air, infrared, and desiccant dryers arecommercially available. Whenever possible, a filter should be inserted in the airtake. This may,however, create such a resistance to the airflow as to require a fan of larger capacity than wouldbe needed without the filter. A removable drip pan beneath each film compartment or drawer isuseful as an aid in keeping the dryer clean. As a precaution, heating elements should beconnected in the fan circuit so that heat cannot be turned on without turning on the fan.Automated ProcessingThe chief difference between processing rooms for manual and automated processing is theabsence of the space-consuming processing tanks. The only part of the automated processorthat need be in the processing room is the film-feeding station, and this is quite small. The planscan follow the general form of Figure 83. Note the provision in the outer (light) room for mixingand storing processing chemicals and washing processor components.In planning a new processing room for an automated processor, early consideration should begiven to providing the water, electrical, drainage, and exhaust facilities required by the processor.Radiography in Modern Industry 130