insulating joints at every place of connection. The insulating joint,
including the pipes, shall be coated with an underground type dielectric
coating for a minimum distance of 10 diameters on each side of the joint.
3.4.5
Ferrous Valves
Dissimilar ferrous valves in a buried ferrous pipeline, including the pipe,
shall be coated with an underground type dielectric coating for a minimum
distance of 10 diameters on each side of the valve.
3.4.6
Brass or Bronze Valves
Brass or bronze valves shall not be used in a buried ferrous pipeline.
3.4.7
Metal Pipe Junction
If the dissimilar metal pipe junction, including valves, is not buried and
is exposed to atmosphere only, the connection or valve, including the pipe,
shall be coated with an underground type dielectric coating for a minimum
distance of 3 diameters on each side of the junction.
3.4.8
Casing
**************************************************************************
NOTE: This paragraph will be deleted if mechanical
and electrical specifications include these
requirements.
**************************************************************************
Where a pipeline is installed in a casing under a roadway or railway, the
pipeline shall be electrically isolated from the casing, and the annular
space sealed against incursion of water.
3.4.9
Test Stations
Test stations shall be of the type and location shown and shall be [curb
box] [post] mounted. Buried electrically isolating joints shall be
provided with test wire connections brought to a test station. Changes in
designated location shall have prior approval. Unless otherwise shown,
other test stations shall be located as follows:
a.
At 300 m 1,000 foot intervals or less.
b.
Where the pipe or conduit crosses any other metal pipe.
c.
At both ends of casings under roadways and railways.
d.
Where both ends of an insulating joint are not accessible above
ground for testing purposes.
3.5
TESTS AND MEASUREMENTS
3.5.1
Baseline Potentials
Each test and measurement will be witnessed by the Contracting Officer.
The Contractor shall notify the Contracting Officer a minimum of 5 working
days prior to each test. After backfill of the [pipe] [tank] [_____] and
anodes is completed, but before the anodes are connected to the [pipe]
[tank] [_____], the static potential-to-soil of the [pipe] [tank] [_____]
SECTION 13112A
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