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5 Vacuum System
Diffusion pump vacuum manifold
Diffusion pump vacuum manifold
The vacuum manifold is the chamber in which the analyzer operates. The mani-
fold is extruded and machined from an aluminum alloy. Large openings in the
side, front, and rear of the vacuum manifold are closed by plates. O-rings provide
the seals between the plates and the manifold. Ports in the manifold and the
plates provide attachment points for the triode gauge tube, calibration valve, vent
valve, GC/MSD interface, and high vacuum pump.
The diffusion pump attaches with a KF50 seal to a baffle adapter that is clamped
to the bottom of the manifold. A vapor baffle helps prevent migration of pump fluid
vapor into the manifold. Cooling fins on the bottom of the manifold keep the baf-
fle cool so the vapor will condense on it.
Triode gauge port
(behind shield)
GC/MSD interface port
Rear end plate
Side plate O-ring groove
Front end plate
Calibration valve port
Cooling fins
Vapor baffle
Vent valve port
Triode gauge port shield