Oil Processing and Fluids

Oil is the wall that separates the early game from the mid game. Up to blue science your factory deals in solids on belts, but chemical (blue) science forces you to set up oil processing, and oil behaves differently from anything before it. Crude oil refines into three fractions at once, and you have to balance all three or the whole refinery backs up and stalls. On top of that, oil is a fluid, and fluids move through pipes with their own throughput rules rather than along belts. Most players hit a real difficulty spike here, which is exactly why the standard advice is to set up oil the moment you reach blue science rather than putting it off and stalling your tech.

Crude oil and refining

Crude oil is mined as a fluid and refined in an oil refinery. The base-game advanced oil processing recipe, a 5 second craft, takes 50 Water and 100 Crude oil and yields 25 Heavy oil, 45 Light oil, and 55 Petroleum gas. The catch is that all three come out together. If you consume only petroleum gas and let heavy and light oil pile up, the refinery fills its outputs and stops, taking your gas supply with it. Balancing the three fractions is the core puzzle of oil, and it is what makes this the first big complexity jump.

Cracking and what the fractions become

Cracking converts surplus fractions downward so nothing backs up. Heavy-to-light cracking consumes 40 heavy oil per 2 seconds to make 30 light oil per 2 seconds; light-to-gas cracking consumes 30 light oil per 2 seconds to make 20 petroleum gas per 2 seconds. From there the fractions feed the chemical layer: petroleum gas becomes plastic and sulfur, and can also become solid fuel or rocket fuel, while heavy oil makes lubricant. A community balancing ratio holds that for every 8 refineries you run 2 heavy-to-light crackers and 7 light-to-gas crackers, though you should treat that as one community figure and verify it against a calculator for your specific build.

Crack your surplus. If you draw only petroleum gas and let heavy and light oil fill their tanks, the refinery stops and your gas dries up. Balancing all three fractions is the whole job.

Fluids and pipes

Fluids, including water, crude oil, the oil fractions, lubricant, sulfuric acid, and steam, move through pipes and are stored in tanks. Pipes have throughput limits that fall off over distance, so a long pipe run carries less than a short one, and pumps boost flow to push fluid further or faster. The 2.0 update reworked the fluid system, so older guidance about pipe behavior may not match the current game. The practical takeaways stand: keep fluid runs short where you can, add pumps for distance, and use tanks to buffer.

Fitting oil into a run

Set up oil as soon as you reach blue (chemical) science. It blocks a lot of tech, and delaying it just stalls you with a half-built tech base. Build the refinery, plumb in water and crude, and get cracking running from the start so the fractions stay balanced. Once oil is flowing you have plastic and sulfur for advanced circuits and the chemical layer, which is what the rest of the tech ladder is waiting on.

Watch out for

• Drawing one fraction and ignoring the others, which backs up the refinery and stalls everything downstream.
• Delaying oil past blue science and wondering why your tech has ground to a halt.
• Running long pipe runs without pumps and quietly starving a distant consumer.
• Assuming pre-2.0 pipe guidance still holds. The fluid system was reworked in 2.0.

Related: The Science Pack Ladder and Key Ratios.