Quantum QT-740, Руководство по обслуживанию

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Chapter 2 Assembly & Installation
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Models QT-740 & QT-750 - Service Manual
ALIGNMENT PROCEDURES
TABLE LEVELING
Before aligning the table to the collimator light field, the table must be leveled.
This is achieved by adding flat shim plates under the 1/2" aluminum base plate.
The shims, which measure approximately 3" x 5", are included with the table
hardware kit.
1. Move the entire table under the collimator, positioning the tray center as close
to the cross-center spot as possible.
2. Place a level on the table or bucky. A double-bubble level at least 18" long is
recommended.
3. If the table is not perfectly level, place the flat shim plates near the mounting
locations as required until the table or bucky reads level.
IMAGE RECEPTOR/COLLIMATOR X-RAY ALIGNMENT
The image receptor must be properly aligned with the projected light field of the
collimator in order to provide accurate x-ray exposures. If the tubestand used
with the table provides transverse travel of the x-ray tube relative to the table, set
the tube transverse travel in the center detent position prior to performing align-
ment.
The following x-ray alignment procedure may require slight repositioning of the
table base. This movement may affect the position or arrangement of the leveling
plates, requiring an additional check prior to final table mounting.
Collimator calibration, tubestand alignments, and collimator light field to x-ray
field adjustments, as described in their respective manuals, must be performed
prior to the following procedure.
1. If the tabletop is installed, remove the radiographic portion of the tabletop,
otherwise, proceed to step 2. The tabletop is held on with dual-lock tape; lift
up a corner then carefully pull the tabletop off.
2. With the collimator parallel to the tabletop (0°), turn on the collimator light.
Using the light field adjusting knobs on the collimator, reduce the light field to
a narrow beam of light along the length of the table.
3. Position the collimator to approximately 24" source-to-image distance (SID).
4. Insert a 14" x 17" cassette into the film tray.
5. Turn on power to the table.