Description Components Safety Radiological Safety Construction, Commissioning & Operation Summary Reactor Vessel Internal Inspection History of FBTR


The Fast Breeder Test Reactor is a 40 MW t, loop type, sodium cooled fast reactor.  Figure shows the schematic flow sheet of the heat transport circuits. Heat generated in the reactor is removed by two primary sodium loops, and transferred to the corresponding secondary sodium loops. Each secondary sodium loop is provided with two once-through steam generator modules. Steam from the four modules is fed to a common steam?water circuit comprising a turbine-generator and a 100% dump condenser. The major characteristics of the reactor are given in Table 1. Stainless steel (SS 316) is the principal material of construction for the reactor and coolant circuits.

Table 1
Main characteristics of the Fast Breeder Test Reactor


Present Core (25th Campaign)
Reactor type Sodium cooled, loop type
Reactor power 27.2 MW t/5.8 MWe
Fuel Pu Carbide + U Carbide
Fuel pin diameter (mm) 5.1
No. of pins/subassembly 61
Maximum linear heat rating (W/cm) 400
Maximum burn-up (GW d/t) 155 (Mark I) / 100 (Mark II)
Peak neutron flux (n/cm2/s) 3.5E15
No. of control rods 6
Control rod material B4C (90% enriched in 10B)
Reactor inlet sodium temperature (deg. C) 380
Reactor outlet sodium temperature (deg. C) 479
Primary sodium flow (m3/h) 924
Feed water temperature (deg. C) 190
Steam temperature (deg. C) 451
Feed water flow (t/h) 45.6
Steam pressure (kg/cm2) 125
Sodium inventory (t) 150
Steam generator Once-through type, seven tubes in shell, serpentine shaped
Turbine-generator 16 Stages, condensing type, 16.4 MWe air cooled.
Bypass circuit 100% Dump condenser