CIANFLONE 2501XBT, Инструкция по эксплуатации и безопасности

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2. X-RAY SAFETY
2-5
Model 2501XBT
Two-Position Sample Holder
Image 2-8
Shifting to Position 1 Analyzing Position 1
Load/Unload 2
Analyzing Position 2
Load/Unload 1
2.6.3 Model 2501XBT Two-Position Sample Holder Interlock Switches
The Two-Position Sample Holder is mounted on top of the Portaspec cabinet.
Mounted on it are the x-ray on light and power light. Its unique design allows the
operator to load or unload a specimen in one position while analyzing in the second.
X-rays can only be generated when two interlock switches sense the final position of
the sample holder slide. When the slide is moved as little as 0.020” from the load
final position, the interlock switches open. Sample Holder interlock switches are part
of interlock circuit number 2. Additionally, the slide ends interlock mechanically
(0.250”) with the sample holder body, further ensuring that x-rays can not escape.
2.7 Portaspec Shielding
The Portaspec has a fixed x-ray output of 10, 20 or 30 kV at 5 mA. This kV
adjustment can only be changed inside of the HV supply and cannot be changed in
software.
Tests have been performed on the x-ray tube output at 30 kV, 5mA. It was found
that using 1/8 inch of cold rolled steel will attenuate the primary x-ray beam to a point
that it is just detectable above background. This test was carried out with the 1/8
inch and ¼ inch cold rolled steel situated at specimen surface plane. The ¼ inch
cold rolled steel fully attenuating the generated x-rays to the background level.
Therefore, shielding of the primary x-ray beam is made from ¼ inch cold rolled or
stainless steel when the x-rays generated are fixed to 30 kV. For Portaspecs fixed to
10 or 20 kV, a minimum of 3/16 inch cold rolled or stainless steel is used.
The Portaspec is made in such a way that there is no shielding accessible to the
operator that can be removed or altered. All joined components that are accessible
to or visible to the operator, have an interlocking machined surface on at least one
surface in order to prevent x-rays from traveling around components.
The primary x-ray beam is focused on to the specimen under analysis with
secondary x-ray scatter shields permanently installed to the x-ray tube housing.