Valves - hdbk1132990185

DOE-HDBK-1132-99

Encasement piping for process lines connecting valve pits or diversion

boxes should be equipped with leak detection systems. In cases where

more than one pipeline terminates in a valve pit or diversion box, the leak

detection system should be designed with the capability of identifying

which line is leaking.

Primary process piping and encasement piping should be provided with

capabilities for periodic pressure testing. The design should restrict the

use of freeze plugs for pressure testing.

Transfer lines terminating at a tank should be provided with pressure

testing capabilities.

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 leak detection.

Process piping carrying radioactive material should be buried

underground or otherwise shielded to provide radiation protection.

Process piping should be equipped with valves at appropriate locations to

facilitate maintenance within ALARA guidelines.

Piping and equipment containing radioactive material should be designed

for ease of decontamination during operations and for ease of

decommissioning after the building life cycle.

Valves. Valves should be located in systems to provide proper isolation for

1.3.9

maintenance tasks, normal operations, and reduced radiation exposure.

II-16