W:\ELECTRICAL\INSTRUCT\FURNACE\FURNACE GENERAL INSTRUCTIONS 2011.DOC
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6 SAFETY EQUIPMENT
6.1
Practically all explosions and fires in furnaces can be traced back to human error. It
should be noted that:
6-1.1
For the protection of personnel and property, careful consideration should be given
to the supervision and monitoring of conditions that could cause, or could lead to, a
real or potential hazard on any installation.
6-1.2
The presence of safety equipment on an installation cannot, in itself, ensure
absolute safety of operation.
6-1.3
There is no substitute for a diligent, capable, well-trained operator.
6-1.4
Highly repetitive operational cycling of any safety device can reduce its life span.
6-2
Electric relays and safety shutoff valves should not be used as substitutes for electrical
disconnects and manual shutoff valves.
6-3
Regularly scheduled inspection, testing, and maintenance of all safety devices shall be
performed. (See Section 7 - MAINTENANCE and Appendix C - MINIMUM PERIODIC
MAINTENANCE REPORT)
6-4
Safety devices shall not be removed or rendered ineffective by bypassing them
electrically or mechanically.
6-5
Minimum safety equipment recommended. Additional safety equipment may be
required for particular applications: (See Appendix A - SAFETY EQUIPMENT,
DESCRIPTION & OPERATION)
6-5.1
For electric furnaces:
-manual reset excess temperature limit interlock
-separate heating element control contactors
6-5.2
For gas heated furnaces:
-manual reset excess temperature limit interlock
-exhauster airflow switch (if so equipped)
-purge timer
-combustion air flow switch
-high gas pressure switch
-low gas pressure switch
-two (2) main safety shut off valves and test stations
-two (2) pilot safety shut off valves and test stations
6.6
No matter how much safety equipment is provided on the furnace, it cannot protect the
operator, other personnel or property from unsafe conditions caused by poor
judgement or misapplication. Common sense must be used for safe operation. If in
doubt, contact the factory. Check the process periodically to ensure furnace is being
used as originally intended.
