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TESTING AFTER INSTALLATION:
In order to prevent time searching for potential leaks, it is recommended that excavation should not be backfilled
until after pressure tests of the pipeline system have been made. After installation, it is desirable to test newly installed
piping sections, including valves, at some pressure above the system designed pressure. The test pressure should not
exceed the rated working pressure of the valve. After the test, steps should be taken to relieve any trapped pressure in the
body of the valve. The valve should not be operated in either the opening or closing direction at differential pressures above
the rated working pressure. It is also recognized that wear or foreign material may damage valve seating surfaces and may
cause leakage.
On completion of the installation, valve location, size, make, type, date of installation, angle to open, direction of opening,
and other information deemed pertinent should be entered on permanent records.
APPLICATION HAZARDS:
1. AVK eccentric plug valves should not be installed in lines where service pressure will exceed the rated working pressure
of the valve.
2. The valve should not be used in applications that are exposed to freezing temperatures unless sufficient flow is
maintained through the valve or other protection is provided to prevent freezing.
3. Pipe, fittings, and valves installed in underground pipelines are generally joined with mechanical joints. These joints are
considered unrestrained-type joints since no considerable restraint against longitudinal separation is provided.
4. Plug valves should not be installed in a dead end or near a bend in a pipeline without proper and adequate restraint to
support the valve and prevent it from damage.
5. It is good engineering practice to consider during the design whether or not thrust blocks, restrained joints, or other
means of restraint are needed on or adjacent to valves on pipelines and/or where unusual conditions exist, such as high
internal pressures, adjacent fittings, or unsuitable soils.
6. The valve should not be used as a lifting device for pipes (or equal) mounted on the valve
