Steam and Condensate Systems

DOE-HDBK-1132-99

Primary and secondary piping should be supported and anchored.

Supports should be adequate to carry the weight of the lines and

maintain proper alignment.

Pipe guides and anchors should be provided to keep pipes in accurate

alignment; direct the expansion movement; and prevent buckling,

swaying, and undue strain. Spider-type supports should be provided

inside the encasement piping to permit lead detection.

Steam and Condensate Systems .

3.1.4

Steam lines should slope 1/8 inch per foot in the direction of steam flow.

Lines with lesser slopes should have provisions for slower warm-up to

allow condensate time to flow to the traps. Condensate removal

provisions should also be placed at shorter intervals to reduce

accumulation of condensate.

Each low point should have a steam trap and free blow with drainage

provisions to a lower elevation. If condensate from steam traps

discharges into a common header, a check valve is typically located

downstream of each trap. The maximum backpressure that is possible in

the header is normally designed to not impede the flow of condensate.

Drip legs should include a steam trap and blowdown drains. For steam

lines less the 3 inches, the drip should be the same diameter as the run

pipe and the blowdown line and valve should be a least inch.

Blowdown (free blow) lines are normally sized to accommodate all

condensation developed during steam line warm up.

Provisions should be made to drain condensate from the upstream side

of isolation valves. Small bypass lines can be installed around pressure

reduction stations and around larger isolation valves. Condensate

drainage from each drip leg is typically adequate for drainage of all

condensate from the full-open warm-up bypass valve. Bypass valves are

II-36