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OPERATION
T
HEORY OF
O
PERATION
Vacuum
Vacuum is supplied by an external vacuum supply (a pump or building system) connected to one of
the oven vacuum ports. Vacuum levels obtained in the oven chamber are dependent on pump type
and performance, valve settings, and the nature of the application or process, including the volume
of materials outgassed.
The chamber atmospheric pressure is displayed on the Vacuum Gauge on the control panel.
The chamber should be sealed and evacuated at the start of a vacuum baking application. The oven
is not built to operate with the chamber exposed to atmosphere. Running the oven with the door or
the vent open risks destroying the vacuum pump, damaging the integrity of the oven chamber, and
may oxidize chamber surfaces.
Vacuum pumps and door gaskets should be selected on the basis of application type or process.
Pumps vary in suitability and safety depending on the outgassed byproduct types and moisture level
produced in the oven chamber. Gasket types have varying resistances and vulnerabilities to different
outgassed chemicals.
Heating in a Vacuum
In conventional ovens, powered elements transfer heat into the chamber air. The heated air then
circulates by natural convection or blower fan action, and surrounds the product on the shelves,
gradually bringing it to temperature. In a vacuum oven, heat transport takes place by both direct
infrared radiation from heated surfaces and from metal-to-metal conduction. The oven heating
elements are located inside the chamber walls or floor, which transfer some heat to the walls and
then to the shelves. Each shelf then transports heat to the products or samples resting on it.
Gas Backfill
A gas or clean air supply can be connected to the vent port (backfill inlet) or KF-25 port located on
the back of the oven. Nitrogen or another inert gas are typically used to avoid particulate or humidity
contamination or the oxidation of product and shelving that has not cooled down. The maximum
allowed backfill pressure is 15 psi of delivery at the port.
Summary of Contents for CVO-2
Page 1: ...Installation Operation Manual CVO 2 Benchtop Vacuum Ovens...
Page 6: ...6 P a g e cascadesciences com Tel 503 847 9047 TABLE OF CONTENTS...
Page 8: ...8 P a g e cascadesciences com Tel 503 847 9047 CERTIFICATIONS...
Page 12: ...12 P a g e cascadesciences com Tel 503 847 9047 SPECIFICATIONS...
Page 20: ...20 P a g e cascadesciences com Tel 503 847 9047 RECEIVING...
Page 30: ...30 P a g e cascadesciences com Tel 503 847 9047 INSTALLATION...
Page 32: ...32 P a g e cascadesciences com Tel 503 847 9047 SYMBOLS...
Page 50: ...50 P a g e cascadesciences com Tel 503 847 9047 MAINTENANCE...
Page 52: ......
