The trapping surface of the center well is visible during operation
through the top view ring. Defrost and clean up of the trap is made easy by lifting out
the trapping well after venting the system to atmospheric pressure.
Generally, a single charge of the dry ice and alcohol mix is enough to last most
of the day. Functionally, the IPA/Dry Ice charge is installed inside the inner well (sump)
so that the air stream will pass around the wells' circumference. Air flow is from the
inlet port to the exhaust port moving around the intervening well. As the contaminant
laden air flow passes around the traps metal well surface, condensable vapors such as
water or solvents will crystallize out of the air stream.
Construction of the DIT is of 304 stainless steel that has been electro-polished
to minimize surface roughness. The outer body wall is .065 inch thick and is stainless
steel with welded-in inlet ports of varying configurations. Vacuum rated silicone grease
is sometimes employed on the rubber gasket used with the well. A thin coating would be all
that is required if determined that the trap is leaking pressure.
Depending on how the trap is ordered it can come configured with hose nipples or
standard ISO flange fittings. In order to hook the trap up on the inlet side of the pump
you need to connect a section of high vacuum hose or tubing between trap and pump. It is
advantageous to determine the sizes desired prior to purchase but these can be easily
adapted after the fact.
The user then connects the trap inlet to the system being evacuated. Pretty
simple and straight forward, but there are obvious benefits to having the port sizes of
the pump, the system being evacuated and the trap all match in (Outside Diameter) size.
The cold well (sump) has a acrylic plastic cover and a rubber gasket which should maintain
vacuum integrity. With long term use, you may find a need to replace the rubber gasket
found between lid and trap top in order to minimize potential leaks. Also be careful as
not to scratch the lids surface where it seals to the rubber gasket and the top of the
trap. |