Elekta Neuromag, Техническое руководство

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NM20216A-F 9
Technical data
1
• Boiloff rate of liquid Helium: max. 8 liters per 24 hours
• Exhaust of Helium gas due to liquid Helium boiloff (+20
°
C, normal
operation at atmospheric pressure): typ. 4 liters per minute
• Helium transfer equipment: see 1.9 below
• Monitoring of the liquid Helium level: integrated sensor and readout
electronics
• Separate local liquid Helium level display integrated inside the gantry
for follow-up during the transfer
• Automatic helium level data gathering to the computer system
• Relief valve opening pressure: 10 kPa (0.1 bar)
• Safety exhaust rupture pressure: 60 kPa (0.6 bar)
• Safety exhaust duct diameter: 60 mm
1.2. Gantry, bed, and chair
1.2.1. Gantry
• Principal material of construction: fiberglass composite
• Measurement positions: upright (helmet tilted 30
°
from vertical),
supine (helmet tilted 180
°
from vertical)
• Dewar movements: Two fixed positions. User controlled up- and
down-buttons and manual latch bar.
• Movement mechanism: Motor-driven rope, controlled by push-but-
tons at gantry. Positions secured by safety latches at upright position
and mechanical stoppers at supine position. Motor located outside the
shielded room. Position indicator display inside the magnetically
shielded room.
• Input power: 230 V~ 47–63 Hz. Separate portable step-up transform-
er if necessary
• Separate docking plate for bed
• Dimensions and weights: see chapter 2
• Side covers under which connectors of auxiliary electronics, EEG,
and the local liquid Helium level display
• Cover of the refill opening including a plug for the fixed siphon
1.2.2. Bed
• Principal material of construction: fiberglass composite
• Method of operation: manual, mechanical
• Movement of lower bed: front/back, turning wheels
• Movement of upper bed: front/back