Pressure Barrel adds a reliable late-game option for interplanetary fluid transport. Zero changes to vanilla progression — just one technology, one recipe, and one new intermediate.

• High-Pressure Barrel — holds 5000 units of any fluid. Cast in a Foundry. Extreme pressure standards mean only 1 in 10 passes; rejects are melted back into molten iron as a byproduct.
• Fluoroplastic — a new intermediate produced from fluorine gas and plastic bars in a Chemical Plant.
• High-Pressure Fluid Handling — a trigger technology unlocked by mining a fluorine vent on Aquilo.

All fluids auto-generate fill/empty recipes. Vanilla barrels are untouched. Purely additive, late-game only.