BERTHOLD TECHNOLOGIES LB 444, Operating Manual

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04/03
347
LB 444
6
3.2 Shieldings
Typically, the source is firmly installed into the working shielding which includes a radia-
tion exit channel to release the active beam towards the detector. The active beam can
be shielded during transport, installation and servicing.
The shielding function must be checked every six months!
3.2.1 Shielding Types LB744... with Manually Operated Lock
The shielding consists of a cast iron or stainless steel outer shell filled with lead, except
for an exit port blocked by a lead filled moveable shutter. The shutter mechanism con-
sists of a rotatable lead filled cup connected to the outside of the housing by means of a
shaft, secured to a handle. The lead filling of the cup has a cylindrical hole. At one dis-
tinct and defined position of the handle, the hole and source holder are aligned, allowing
the radioactive beam to reach outside via a steel cover plate.
This is the “on” position of the device. At all other shaft positions, the beam exit is
blocked by the lead in the cup. The handle which indicates the open or closed condition
of the shutter can be secured in either position against unauthorized manipulation. Ac-
cess to the source holder is prevented by the handle in both the open and closed posi-
tions.
2 1 7
8
Pb
3 3.1 4 5 6
Figure 3: Shielding container type LB744
1 Shell 4 Radiation source
2 Moveable shutter 5 Source holder
3 Radiation exit channel, “OPEN” 6 Locking lever
3.1 Radiation exit channel, “CLOSED” 7 Lock
8 Cover plate