Orion Instruments Atlas - Manual (Page 7)

46-638 Magnetic Liquid Level Indicators 7
1.8 Special Accessory Installation
1.8.1 Insulation or Blanket Installation
Factory recommended high temperature insulation specifications:
Temperature Thickness Liner Jacket
0° to +250° F (-18° to +121° C) 1 ⁄
2
"
Weather resistant silicone cloth
+251° to +500° F (+122° to +260° C) 1" Weather resistant silicone cloth
+501° to +1000° F (+261° to +538° C) 2" Weather resistant aluminized silicone cloth
• Thickness is 1 ⁄
2
" when the MLI has switches or a transmitter.
• Insulation used is 8 lb. density ceramic blanket
• All removable insulated blankets are fastened to the MLI by
velcro and straps. Quilting pins available as an option.
• All removable insulation blankets are sewn with fire retardant
teflon thread.
• High temperature guide for the level flow gauge side mount:
Consult factory for specific temperature guide lines.
Figure 1
Low Temperature
Insulated Magnetic
Level Indicator
• Purpose: To maintain the required low temperature of the
service fluid to be measured.
• All insulation joints will be staggered.
• All insulation joints will be sealed with a non-breathing
moisture resistant mastic.
• All weather resisting jacketing seams will be sealed with a
weather resistant caulk.
• The weather resistant jacket will be sealed to the 2" or 4"
plexiglass frost extension, with weather resistant caulk.
• The face of the frost extension must always be exposed.
• Cryogenic units will be flipper style indicators.
Factory recommended cryogenic insulation specifications:
Temperature Thickness Liner Jacket
+32° to -100° F (0° to -73° C) 2" Outdoor .016 smooth aluminum Polyurethane with all
-101° to -320° F (-74° to -196° C) 4" jacket with vapor barrier service jacket vapor barrier