The cover illustration of this brochure directly features some important results of this synergy.
The front surface of the sterilization unit is perfectly "clean", and of course so is the rear one which faces the sterile area.

All the visible hinges, handles and related chromium-plated lever systems for locking, not to mention the antiquated eyebolts, have been eliminated. The same applies to the panels screwed onto the front to provide access to the electric heaters and to the water-cooled heat exchanger. Automatic door locking is provided by an electric piston motor located inside the cabinet to the side of each door.

The insulating, ergonomic handle recessed in the door is used only to gently lead it manually in its opening/closing movements.

Placement next to Fedegari autoclaves produces a perfect result both functionally and aesthetically; the computerized process controller is identical for the two units. Sterilization-depyrogenation units of the FOD series are generally managed by the Superspectra computerized process controller, which is reconfigured for the specific task. We strongly recommend this type of management which allows high flexibility in process customization, extremely accurate real-time calculations as well as detailed permanent documentation, including the Fh - Ft values supplied to the load and detected by each one of the four flexible heat probes inside the chamber. Please refer to the specific brochure for a description of the Superspectra process controller.

It is known that the pressure in the chamber must remain, throughout the process, slightly higher than in the non-sterile area and slightly lower than in the sterile area.
In conventional machines, this is somewhat precariously achieved by operating a damper on the discharge duct, which adjusts the outgoing flow.

In this new generation of sterilization units, this damper has been eliminated and pressure in the chamber is controlled by varying the speed of the chamber pressurization fan; pressurization is adjusted with a proportional action by the process controller.

The doors are made of just two parts, an internal one and an external one, both of which are made of stainless steel formed on a bending press. The coupling of these two parts produces a thermally self-compensating structure which remains perfectly flat in the course of time: naturally, this is essential for the tightness of the door gasket.

By virtue of sophisticated constructive solutions, the coupling of these two parts also forms the seat for accommodating the gasket.

This recess has a trapezoidal cross-section and corners which have a wide bending radius. The silicone rubber gasket also has a cross-section which is designed specifically to fit in the seat and to remain perfectly in place without requiring any retention device. The gasket is of the extruded tubular type and is obtained from a single piece of material which is butt-welded without further joints.

The two metal-plate parts which form the door are coupled after filling their interspace with thermally insulating material.
The regions where the metal plates overlap have rigid ceramic insulation material interposed in order to avoid forming thermal bridges.

Three types of material are used in combination for the general thermal insulation of the sterilization units: rigid ceramic insulation for areas subject to compression stresses, insulation with a soft ceramic matrix and rock wool for other areas. The insulation of both fronts and bottom is contained in stainless steel sheet metal while side and top insulation is contained in aluminum sheoting; the sheet overlap regions are sealed with silicone adhesive.
The result is that the temperature of the external surfaces of the sterilization unit does not exceed 40°C when the chamber temperature is mantained at 240°C.

A port with a 40 mm diameter is provided as a standard fitting for validation

temperature probes.
A sampling port with a 3/8" diameter can also be installed as an optional fitting for particulate tests.

CONSTRUCTION AND APPLICATION FEATURES

The sterilization units are made of AISI 304 stainless steel as standard, including:

• the supporting structure of the cabinet, which is made of tubes with a square cross-section
• the chamber supporting stand
• the electric heaters
• the water-cooled heat exchanger
• the covering of the lower thermal insulation and of the two front panels (only the top and lateral covering is made of aluminum sheet)
• the circulation fan impellers
• all the connections to the chamber.

Operating temperature is adjustable between 140 and 250°C; wider ranges can be provided on request.
The flexible temperature probes have a special sheath produced by means of a sintered wrapping made of homopolymeric PTFE in order to withstand even the highest treatment temperatures without problems.