The steel plate structure

The approximate overall size is as follows 16 ft in the north-south direction, 14 ft in the east west direction, and 12 ft 6 in. in height. The thermal shield, whose heat generation, rate is approximately 95 kw, is cooled by an induced-draft air system which also serves as the graphite cooling system (see Section 2.7.2). The primary supporting structure is composed of four vertical WF columns with the load transmitted to these columns at the four corners of the bottom plate. 

The bottom plate of the lower thermal shield, while resting directly on the steel supporting structure, is in direct contact with the barytes concrete below it. This helps to. cool the concrete by direct thermal contact. The upper plate of the lower thermal shield is in two parts. An inner ring 14 in. wide is welded directly to tank section E (see Fig. 2.E) in order to provide maximum cooling for this section.The outer, section is supported from the lower plate and is air cooled only. 

Two important experimental facilities, the thermal column and the shielding facility (see Sections 3.1 and, 3.2j, require that a section approximately 6 by 6 ft be removed from.the east and west thermal-shield side plates. Two components are added to the thermal-shield design by.these facilities (1) the neutron window, and (2) the neutron-absorbing curtain. The locations of these components may be visualized by referring to Figs. 2.B and C. When the 6- by 6-ft hole is cut in the thermal shield, it becomes necessary to replace 

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