FVA THIRD-GENERATION VERTICAL SATURATED-STEAM STERILIZERS

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2 The key difference between a small vertical or bench-top sterilizer and industrial sterilizer is performance. Small saturated-steam sterilizers with vertical or horizontal chambers were devised many years ago to process small amounts of solid and liquid products, as required mainly by analysis laboratories surgeries. Through the years, owing to the gradual expansion of the field of application of sterilization processes, which has made them indispensable in many important context of human life, these machines bear ever-increasing responsibilities. However, perhaps because of limited applicable standards in this field, their relatively low cost or the scarcely diversified experience of some manufacturers, these sterilizers have not benefited from the considerable technological evolution that has affected industrial machines, especially those used by the pharmaceutical industry, and have remained so to speakglorified pressure cookers. Although some manufactures have proved their worth by offering different technical principles, on the whole, small laboratory sterilizers were (and still are) purchased when limited financial resources do not allow, or do not justify, the installation of a more sophisticated machine. In early 1994 Fedegari, aiming to devise a future generation of laboratory sterilizers, started a highly rewarding dialog with users and vendors in order to understand the main shortcomings or critical aspects observed through daily use of these machines. Careful analysis showed demand for the following characteristics: fully automated operation process flexibility higher productivity low maintenance higher process performance better ergonomics limited cost. To provide easier loading/unloading of the materials, the loading level of the sterilizer has been reduced to only 850 mmfrom the ground. Using its vast experience, acquired by meeting the ever-increasing demands of pharmaceutical industries, Fedegari accordingly started to develop the prototypes of what can now be considered as the third generation of laboratory sterilizers, which is herein described. Even the external structure of the machines is altered with respect to the previous generation: the technical area meant to accommodate the actuators and the control equipment is in fact larger, in order to install all the electrical, electronic and piping devices required to perform the various processes. Sterilizers of the series, with the aid of suitable equipment options, can perform sterilizations of solids with initial vacuum and with final vacuum for drying the load; sterilizations of liquids in open or closed containers, with indirect cooling by means of an internal heat exchanger and a fan (with a magnetic-drive coupling) and sterile air counterpressure; sterilizations of highpathogen loads with no external treatment of the infected effluents; chamber vacuum or pressure tightness tests; the Bowie & Dick test; monitoring and control of processes based on the F 0 value, etc... Sterilizer equipped with the (optional) cycle for forced load cooling by means of a magnetic-driven centrifugal fan installed in the hollow of the lid.

3 The technical area now also includes a small independent electrical steam generator which is equipped with a pump for automatically feeding the deionized water. Therefore, the steam required for the process is no longer produced inside the sterilization chamber or inside the jacket but is constantly supplied by the generator. This solution offers significant advantages, such as reduction of bad odors and elimination of any corrosion caused by stagnation of water, which may be contaminated by the leakage of product from the load, on the bottom of the sterilization chamber. If the user has steam available, this option can be eliminated. The lid for closing the chamber has also been completely redesigned: in order to reduce maintenance and increase operator safety, the lid is conceptually identical to doors of industrial sterilizers, without closure lever systems and with the now thoroughly tested dovetail pneumatic gasket, patented by Fedegari for its sliding doors. The safety of this solution is absolute, also by virtue of a system of mechanical interlocks between the lid and the chamber which prevents opening in the presence of residual pressure. Rear view of sterilizer: notice the connectors for hook-up to the utilities. The piping is entirely made of AISI 316L stainless steel and has been engineered in the same way as that of industrial sterilizers, using sanitary-type quick-couplings and pneumatic valves with a special PTFE membrane. The lid gasket, like pneumatic valves, is fed by a small electric air compressor, which is also located in the technical area. This option, too, can be eliminated if the user has compressed air available; compressed air is any way indispensable to perform processes which include the above described forced cooling of the load. Pneumatic gasket, partially extracted from its seat. Bottom view of cover, dearly showing the centrifugal fan and the heat exchanger of the forced cooling cycle.

4 From the point of view of process control, Fedegari has succeeded in achieving a high level of modularity, flexibility and performance also by using a PLC and appropriate sensors. The process software has been designed by Fedegari, starting from the software developed a few years ago for controllers of the SUPERSPECTRA series. By virtue of the computing power provided by the software of the PLC, the operator can also choose to control the sterilization phase according to the accumulated F0 value or to simply print it out; in any case, process documentation provides irrefutable evidence and ensures the necessary traceability. By using appropriate security passwords, the user can customize the sterilization process or create new ones to treat specific products. In addition to fully automated operation, this kind of software offers a series of operating safeties and alarm which cannot be obtained otherwise. Fedegari has also made provisions for connecting the sterilizer to remote controllers by means of an RS232 serial port; this allows to integrate the machines in any monitoring and control network. The electric panel is installed in a hinged case. Opening this case allows access to the technical area for maintenance. Many other innovations, which would be lengthy to list here, have been introduced in sterilizers of the series with respect to previous ones. To appreciate in greater detail the remarkable potential offered by this new generation of sterilizers, you should contact our Sales Department or our local agents and dealers. Operator interface with LCD and keyboard. Finally, Fedegari has sought to improve the overall ergonomics of the machine by reducing the loading level, in both models, to only 850 mm from the ground, accordingly making loading and unloading less tiring for the operator. Port for inserting the validation thermocouples, allowing to insert up to 12 thermocouples in the chamber.

5 Pneumatic sanitary type diaphragm valves, without shutter seal, designed and manufactured by Fedegari. 2 The pressure transducer replaces the old analog pressure gauge with adjustable electric contacts. 3 Air sterilization filter. 4 Electric air compressor for feeding the gasket and the pneumatic valves. 5 Liquid-ring vacuum pump, allowing to attain a vacuum of 150 mbar in the chamber in approximately 150 seconds. Independent electric steam generator. The electric heaters of the generator can be removed from above. Pump for automatically feeding D.I. water to the steam generator. Electric panel in the open position. Piping system made of AISI 316L stainless steel, with sanitary-type quick couplings. 11 Emergency pushbutton. 12 Manual chamber drain valve. 13 Analog pressure gauges for chamber and steam generator

6 CHARACTERISTICS 2 3 CHAMBER INSIDE DIAMETER CHAMBER USEFUL DEPTH CHAMBER NOMINAL CAPACITY MAXIMUM WIDTH MAXIMUM HEIGTH MAXIMUM FUORI DEPTH MAXIMUM OPERATING PRESSURE MAXIMUM OPERATING TEMPERATURE [ l ] [ bar ass. ] [ C ] , ,5 138 ELECTRIC POWER SUPPLY 400V, 50Hz 3 Ph-N+PE INSTALLED POWER WITH STEAM GENERATOR [ Kw ],5 INSTALLED POWER WITHOUT STEAM GENERATOR 1,5 ALTRE UTENZE P abs. bar 2 3 STEAM (IF STEAM GENERATOR NOT ISTALLED) peak flow-rate average consumption per cycle D.I. WATER FOR STEAM GENERATOR peak flow-rate average consumption per cycle TAP WATER for vacuum pump for drain cooling for load forced cooling COMPRESSED AIR for feeding lid gasked/valves for counterpressure in chamber [ kg/h ] [ kg ] [ l/h ] [ l ] [ l ] [ NI/min ] The above mentioned data are to be intended as indicative. The manufacturer reserves itself the right to change them without notice. 4, ,5 4, Albuzzano (PV) - Italia - tel fax