Recommended design practice for divertors

DOE-STD-6003-96

4. Irradiation Effects--The effects of irradiation-induced hardening, loss of ductility,

swelling, creep, and changes to other material properties must be considered in

design and analysis of the divertor as well as in the formulation of structural

design practices and criteria.

c. Recommended design practice for divertors

To minimize the potential for and/or consequences of off-normal events, the following

practices are recommended for divertor design:

minimization of coolant temperatures and pressures,

use of double-contained coolant wherever reasonable,

minimization of chemically reactive materials,

minimization of radioactive dust and tritium inventories through appropriate,

selection of plasma-facing materials.

The items listed above serve only as guidance in the design process. Divertor designs

which result from compromises between the above practices and overall performance of the

fusion device are acceptable as long as they do not lead to a conflict of any of the safety design

guidance presented in this document.

Because of the effects of neutron irradiation, welding of structural materials in the divertor

region should be avoided. If unavoidable, welds should be located in regions of low stress.

Stress limits for irradiated weld material should receive special consideration in the structural

design criteria.

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