Radiation Shielding Seals

DOE-HDBK-1132-99

Radiation Shielding Seals .

Determine the project criteria for the degree of radiation shielding

required at penetrations. Provide calculations to support the shielding

criteria.

Select penetration sealant material based on satisfactory performance of

sealant in meeting project radiation shielding criteria, life expectancy of

sealant in radiation environment compatibility with adjacent materials, and

constructibility.

Consider external mechanical loads on penetrating element (pipe, etc.)

and differential movement between penetrating element and structure

that may cause the seal to fail or be dislodged.

Jumpers.

1.5

1.5.1

General Jumper Design Considerations . Chemical processing vessels in

nonreactor nuclear facilities often are located in areas of high radiation with very

limited access capabilities. In order to transport process materials as well as the

services required for the process, pipes are fabricated with the capability of being

installed remotely by cranes. Such pipes are called jumpers. Jumper design

requires many special considerations in addition to normal needs, which are

discussed in this section.

Pipe jumpers are installed by remotely operated cranes between the

vessel nozzles and wall nozzles by means of connector blocks. The

installation is performed by using an impact wrench mounted on the crane

hook. Since the installation is performed by the operator at a remote

location, the tolerances are evaluated based on:

the ability to remotely lower the pipe into the connected nozzles

(i.e., tighter clearance tolerances make the installation process more

difficult);

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