Section 5. TRAPS
1 DESCRIPTION. Traps drain condensed moisture from intercoolers,
aftercoolers, receivers, and distribution piping. The most common traps are
the ball float trap, bucket trap, and inverted bucket trap (figure 4-7). An
in depth discussion of traps is found in NAVFAC MO-209, Maintenance of Steam,
Hot Water, and Compressed Air Distribution Systems.
2 STARTUP. Some compressed air drain traps must be primed before placing
them in service. This is done by filling the trap half full with freshwater.
3 SHUTDOWN. If the compressed air system is not in operation and the drain
traps might be subjected to freezing temperatures, thoroughly drain the traps
of all condensate to prevent damage from freezing.
4 PREVENTIVE MAINTENANCE INSPECTION.
4.1 Daily Inspection. Check the operation of drain traps daily. Make sure
the trap is draining properly and not blowing air.
4.2 Periodic Inspection. At intervals prescribed by the manufacturer's
maintenance schedule, dismantle the trap. Parts should be cleaned and
evaluated as to their ability to perform satisfactorily until the next
scheduled periodic inspection. Inspect the trap for the following conditions:
(a) Corrosion and erosion
(b) Damaged or excessively worn valves and seats
(c) Defective float or bucket
(d) Loose, damaged, or excessively worn linkage and pivot points
Do not attempt to repair or remove any compressor system parts
without first relieving pressure from the entire system.
Do not use gasoline,kerosene, or other low flashpoint solvents. A
serious explosion may result.
5.1 Cleaning. Frequency of cleaning depends upon the condition of the system
and whether or not a strainer is installed ahead of the trap. Thoroughly
clean trap internals. Remove all dirt accumulations from the trap body and
mechanism, using detergent and water, or an approved solvent if necessary.
Valve seats may be cleaned using a small spiral brush.