Gas Pipe

Gas Pipe is the basic ventilation conduit used to connect the inputs and outputs of ventilated buildings. It forms one of the three pipe systems in the game, alongside Liquid Pipe and Conveyor Rail, and follows the same general simulation rules: gases are moved through the network without being affected by gravity. A gas pipe network also supports the usual utility buildings such as bridges and valves.

Each gas pipe segment can hold 1000 g of gas. The system updates once per second, and a packet can move from one pipe segment to the next during that update, so the maximum throughput of a single continuous line is 1 kg/s. Because the system works in discrete packets, the size and direction of the network matter when designing efficient ventilation.

Gas Pipe tiles can occupy the same space as other buildings, but not other Gas Pipe segments. The ventilation overlay highlights all gas pipes, building intakes, and outputs, which makes it easier to trace a network and spot missing connections or routing problems.

Gas pipes exchange heat with the gas inside them, and the pipe segment also exchanges heat with the tile it occupies. The thermal conductivity of the pipe material is an important part of that exchange. Among available building materials, Granite has the highest thermal conductivity, while Ceramic has the lowest before Thermium and Insulation become available. A pipe segment does not exchange heat with neighboring pipe segments, so heat transfer occurs through the gas and the tile, not along the line itself.

Several practical behaviors make Gas Pipe useful in both ventilation and temperature management:

• When a pipe network connects more than one output and intake, avoid bidirectional flow. The simulation can flip gas back and forth if it is unsure which direction a packet should move. Gas Valves and Gas Bridges can be used to force direction.
• Because Gas Pipe is not insulated, its contents are exposed to temperature changes. This can be exploited to build cooling systems by moving insulated gases such as Hydrogen into an area, then switching to normal pipes so the room can shed excess heat into the gas.
• If gas in a pipe changes phase into liquid, the pipe can be damaged. Keeping packet size reduced to 100 g helps prevent this.
• Building pipes through natural tiles will mine out those tiles.
• Regular Gas Pipe has no decor penalty.

Gas Pipe is therefore both a core logistics building and a useful thermal tool. Its simple routing rules, visible overlay support, and interaction with heat make it central to most ventilation systems, from basic oxygen distribution to more advanced environmental control.