Average Service Life
Between Replacement
Type of Trap
or Repairs
Impact-operated traps
19 months
**************************************************************************
Steam traps shall be in accordance with ASTM F 1139, type, style, and class
as applicable.
2.19.1
Bucket Traps
Bucket traps shall be, either the inverted bucket type or the vertical
bucket type with automatic air discharge. The traps shall be designed for
a working pressure of 1.03 MPa 150 psig, but shall be in the correct
pressure class to operate properly at the actual steam supply pressure
indicated for the system. Valve and seat shall be constructed of stainless
steel. All other interior parts shall be of corrosion-resistant metal and
the traps may be sealed type with corrosion-resistant steel bodies. Traps
shall discharge the condensate to the return line and shall be connected as
indicated. A suitable strainer with blow-off valve shall be installed in
the intake connection to each trap. Capacity of traps shall be not less
than that indicated.
2.19.2
Impact-Operated Traps
Impact-operated traps, impulse-operated traps, or thermodynamic traps with
continuous discharge may be installed in lieu of bucket traps if
applicable, subject to approval of the Contracting Officer.
2.19.3
Thermostatic Traps
Thermostatic traps designed for a steam working pressure suitable for the
application may be furnished in lieu of the traps specified above if
applicable. Thermostatic trap capacities shall be based on a pressure
differential not in excess of the following:
Steam working pressure
Differential pressure
275-350 kPa
240
kPa
40-50 psig
35
psig
620-690 kPa
550
kPa
90-100 psig
80
psig
2.19.4
Float and Thermostatic Traps
Float and thermostatic traps shall be designed for a steam working pressure
of 103 kPa 15 psig but shall operate with the supply pressure indicated for
the system. The trap capacity shall be based on a pressure differential of
15 kPa 2 psi. The inlet to each trap shall be provided with a brass or
stainless steel strainer either separately or as an integral part of the
trap.
2.20
PRESSURE GAUGES
Pressure gauges shall be heavy-duty industrial type with phenolic case,
solid front, rear blowout, threaded ring, shatterproof glass, and 13 mm 1/2
inch NPT bottom connection suitable for specified pressure or vacuum with
minimum 114.3 mm 4-1/2 inch diameter dial, except as other-wise specified.
SECTION 15559A
Page 66
Previous Page
