Rice Lake IQ plus 810 XPCD Installation Manual page 5

Propagation of Gas due to
Pressure from an internal
Explosion is along the
threads
High Temperature
The push buttons, rotary switches and sealing fittings are all attached to the enclosure via drilled and
tapped holes in the enclosure. Just as with the flange, all threaded operators and fittings carefully control
the flame path.
2 IQ plus 810 XPCD Installation Manual
HAZARDOUS
Lower
Temperature
Gases
Shaft Clearance
not to exceed valve
Gases
INSIDE OF
ENCLOSURE
Enlarged view
below
Explosion
AREA
Cooling from
Conduction of Heat
along the Threads
There must be a minimum of five full
Cross–Section of a
shaft-type threaded
operator
threads of engagement of a 2–A
2–B fit for a Group C enclosure.
Group B increases this to eight full
threads of engagement.