Going Nuclear: RBMK reactor construction and operation
Handbook · Physics · Next: Waste and MOX
The RBMK is the second reactor type in 0.512-5-1. It uses graphite moderation and boiling water in pressure channels. Build it from its own component family; changing a BWR's controller alone does not make an RBMK.
Components
| Component | Position and function |
|---|---|
| RBMK Biological Shield | Floor, walls and roof edge |
| RBMK Graphite Column | Graphite between channels |
| RBMK Fuel Channel | Continuous vertical fuel/pressure columns |
| RBMK Control Rod Channel | Separate vertical rod columns |
| RBMK Upper Shield | Top closure over fuel channels |
| Control Rod Drive | Roof, above each rod-channel column |
| RBMK Control Console | Shield wall |
| RBMK Nozzle | Fluid ports |
Ordinary BWR components do not belong in the structure. The scanner reports foreign blocks, wrong edges and missing channels. Control Rod Drives are shared.
Construction sequence
- Build a closed Biological Shield floor and plan waste extraction.
- Build the graphite stack with continuous fuel and rod channels.
- Close the walls, adding the Console and RBMK Nozzles.
- Cap fuel columns with Upper Shield and finish roof edges with Biological Shield.
- Put a rod drive above every rod-channel column.
- Configure fuel, waste, steam, water and relief ports. Complete cooling and turbines.
- Scan and resolve every structural message before startup.
The “The RBMK” Ponder scene helps with spatial placement. The following plan is derived from the installed RBMK Builder. Like the BWR example it is 5×5×6, but its core, ports and roof are different.
Layer plan
View each square from above, north at the top. Layer 0 is the floor; layer 5
the roof. S = Biological Shield, F = RBMK Fuel Channel, T = RBMK Control
Rod Channel, R = Control Rod Drive, U = Upper Shield. K is the Console
facing south. A/H/W/B/E are Waste/Hot Leg/Cold Leg/Fuel/Relief RBMK Nozzles.
Layer 0:
SSSSS
SSSSS
SSASS
SSSSS
SSSSS
Layer 1:
SSSSS
STFTS
SFFFS
STFTS
SSSSS
Layer 2:
SSSSS
STFTS
SFFFS
STFTS
SKSSS
Layer 3:
SSSSS
STFTH
SFFFW
STFTS
SSSSS
Layer 4:
SSSSS
ETFTS
SFFFS
BTFTS
SSSSS
Layer 5:
SSSSS
SRURS
SUUUS
SRURS
SSSSS
Materials: 99 Biological Shields, 20 Fuel Channels, 16 Control Rod Channels, 5 Upper Shields, 4 rod drives, 5 RBMK Nozzles and 1 Console. All nine interior positions of each core layer are channel blocks containing graphite. This compact layout needs no additional Graphite Columns. Larger or different layouts use those between channels. Temporary graphite that the Builder replaces with a channel is not an additional final component.
Scan the finished structure. This source-derived plan still awaits an in-game construction and startup acceptance test.
Positive void feedback
Steam bubbles can increase RBMK reactivity. More boiling can produce more power, causing more boiling in turn. Water loss therefore cannot be treated as reliable self-shutdown.
Maintain water supply and monitor power, period, water and pressure together. Use the Physics Desk and leave pumping and steam-intake reserves. Experiments with marginal cooling or heavily withdrawn rods belong outside a valuable world.
Rod reserve and slow SCRAM
The bundled guide says to keep at least 15% insertion; below that, the controller warns about lost margin. This is a lower bound from the guide, not a guaranteed safe operating position.
RBMK SCRAM takes 18 seconds according to Ponder. Graphite tips initially can raise power. The general instant-rod-drop tooltip does not describe this adequately. Act before cooling and power growth are out of control. Follow the emergency procedure, remembering that delayed rod response makes the situation more urgent.
Shared systems and mobile reactors
Enrichment, steam transport, turbines, measuring instruments and waste handling are shared. MOX changes response further; learn RBMK operation with predictable fuel before changing geometry, fuel and load simultaneously.
The version declares optional Create Aeronautics/Sable compatibility. That does not establish a tested mobile-reactor design here. Cooling and protection requirements still apply on a ship; this handbook has not verified ship operation.