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 Section 5.
STEAM TRAP MAINTENANCE PROGRAM
1 MAINTENANCE PROGRAM. S t e a m traps, like all other components of utility
systems, have a structured maintenance program to ensure system integrity,
energy conservation, and cost reduction. The program must be well planned and
conscientiously implemented.
1.1 Trap Replacement. The economic comparison between losing steam and
repairing or replacing steam traps can be estimated. The difference in costs
of a neglected system and a regularly maintained system can also be
estimated. As traps wear with age, the steam used to make a trap function
i n c r e a s e s approximately 3 pounds per year for the first 3 years. After that,
it can increase by as much as 8 pounds per year. T h e following empirical
formula is the result of a study at the Navy Post Graduate School, Monterey,
CA. It may be used as a guide for optimum time for trap replacement.
Time in service (years) =
Cost of trap replacement ($)
11.3 x Cost of steam ($/Mlb)
For example, if a trap costs $250 to replace and steam costs $10 per pound to
produce:
Time =
= 1.5 years
$250
11.3x$10
This
formula illustrates that a relatively small quantity of steam lost each
hour
can make frequent trap replacement economical. Experience and discretion
be used when determining trap replacement. Replacement time depends a
must
great
deal upon the trap type and design.
1.2 Continuous Maintenance. Industry experience has shown that in a system
which is without a planned program, between 10 and 50 percent of the traps may
be malfunctioning at any one time. I n a system which produces 300 million
pounds of steam per year at a total cost of $3 million, approximately 75
p e r c e n t of the cost is fuel (a direct variable cost). A 1 percent improvement
in the efficiency of the system through steam trap inspection and maintenance
could save over $20,000 a year in fuel costs.
1.2.1 Program Establishment. The following steps should be followed in
setting up an effective program of steam trap inspection and maintenance.
( a ) Baseline Survey. T h e initial survey provides or verifies records of
steam trap location and type, provides a steam trap map, determines the
b a s e l i n e condition of the trap inventory, and checks installation and use for
Refer to figure 3-6 for an example of a format that could be
misapplication.
used during a baseline survey of steam traps.
( b ) Establish System Standards. Standards for types, sizes, and
i n s t a l l a t i o n of traps eliminate misapplication, reduce inventory and system
costs, and provide a basis for budgeting and trap replacement planning.
( c ) T r a i n i n g . As a formal program is established, the people involved
i n operation, inspection and maintenance, energy conservation, and engineering
must be trained and indoctrinated in the goals of the program.
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