Reactor Shielding Design Manual

This manual describes the procedures and data which are used in the design, construction, and testing of shielding for the reactor plants of the Naval Reactors Program and for the Shippingport Pressurized Water Reactor (PWR). These procedures are quite different from those practiced on other projects. The fact that these techniques-developed originally for naval reactor applications-apply so directly and so well to the PWR makes it apparent that this manu& micht be useful tc other projects outside the Naval Reactors Program. It should not be assumed that careful shield design is important only for mobile reactor plants. Poor shield design in a stationary reactor can lead to high costs, poor maintenance accessibility, high radiation levels near shield penetrations or stiffeners, or excessive stresses due to nuclear heating in structures near the reactor core. Inadequate design of the reactor shield can result in activation of primary coolant equipment, decomposition of water in the heat exchanger (perhaps aggravating corrosion), or radiation damage to the material of the primary shield itself. The detectors upon which the reactor control system depends are designed around fluxes calculated by the shield designer; err o r s here can result in blind reactor start-ups or burned-out detectors. The methods discussed in this manual have two salient features: (1) They have been actually used for, and tested ‘on, real power reactor shields and (2) they form a basic approach rather than a mock-up approach and thus permit design of shields without expensive and time-consuming use of the reactor facilities in which full-scale shielding mock-ups can be made. This manual should simplify and lessen the time required for desigri of power reactor shields. The quintessence of a great deal of practical experience is contained in this manual. Many theoretical methods that looked appealing on paper were found in practice to be of liffle practical value. Most of the difficulty in designing a practical shield comes from the layout, structure, and irregularities of an actual reactor plant and notin the mathematicalanalysis of an idealized reactor concept; these concepts never have any sharp corners, gaps, streaming paths, or clearances. In this regard a fact which