[Factorio] Oil Refinery Layout and 20:5:17 / 8:2:7 Ratios

After blue science in Factorio, it's more stable to launch your oil line with a minimal basic oil processing setup rather than jumping straight into advanced processing. This guide is for players who've experienced the frustration of jams—the moment you start running plastic and sulfur simultaneously, one oil type fills up and your entire refinery halts.

I've been there too. The instant I spun up plastic and sulfur together, light oil maxed out alone, and the backup propagated all the way to petroleum gas, silencing the entire line. From there, after reviewing the ratios, I arrived at a workflow: start with basic oil processing producing 9 petroleum gas per second immediately after research, and when space opens up, transition to the 20:5:17 (practically 8:2:7) advanced configuration, with the principle that heavy oil feeds lubricant first, and only surplus flows to cracking.

Oil processing is tricky because if any output line maxes, everything shuts down. That's why this article focuses less on the advanced configuration itself (which can scale to 19.5 petroleum gas equivalent per second), and more on the core principle: designing pump and storage priorities actually matters. I'll walk through the numbers and layout thinking.

Foundational Knowledge: Refinery and Cracking Design

Target Versions (Vanilla / Space Age) and Article Scope

This article centers on vanilla 2.0 baseline. That means crude oil processing in oil refineries and, as needed, cracking (decomposing higher-tier oil into lower tiers) in chemical plants to manage heavy oil, light oil, and petroleum gas flow. Factorio's oil line looks simple—"just three fluid outputs"—but if even one type jams, the whole system stops. It's a classic early stumbling block.

What I always keep in mind at this stage is less the recipes themselves and more the pipework layout that'll later scale to advanced setups. Even starting from basic oil processing, the crude oil input and petroleum gas output positions align well with advanced oil processing, so if you design it for easy recipe swaps after research, you avoid wasteful rebuilds. Using ALT mode to see input/output positions while pre-laying just the crude and gas trunk lines makes future revamps far easier.

Space Age does introduce differences in oil processing specifications. The Advanced oil processing (research) - Factorio Wiki design itself reflects the intent to support progression from basic setups. However, for this guide's purposes, establishing the design principles that work in vanilla first is more valuable than chasing every Space Age number difference. Space Age does expand ways to generate heavy oil outputs from coal and simplifies lubricant startup in some scenarios. But the core issue—that oil lines are "easily-clogged multi-output systems"—hasn't changed.

When you run plastic and sulfur together, basic oil processing's 9 petroleum gas per second starts feeling pinched faster than the numbers suggest. That "technically running, but struggling once we expand" feeling right after blue science? It comes from here. Understanding this feeling clarifies why switching to advanced processing is so valuable.

The Difference Between Basic and Advanced Oil Processing

The gap isn't just "later-game recipe, better output." The design philosophy itself differs. Basic oil processing transforms crude oil into petroleum gas alone. One oil refinery produces 9 petroleum gas per second, and with a single output type, setup is refreshingly straightforward. When you're racing to get plastic or sulfur online, that simplicity is a genuine strength.

Advanced oil processing, by contrast, produces three types simultaneously: heavy, light, and petroleum gas. At first glance, "why add two unwanted byproducts?" But pair this with cracking and the evaluation flips. Decompose heavy oil into light oil, then light into gas, and one refinery's petroleum gas equivalent rises to 19.5 per second. Against basic's 9, advanced's responsiveness to gas demand jumps dramatically.

However, raw numbers don't work in isolation. Advanced processing halts the entire refinery if any output maxes. The configuration's real essence isn't "producing three types at once"—it's needing constant surplus spillage design through cracking. That's where cracking equipment ratios become critical.

A practical standard ratio is advanced oil processing : heavy oil cracking : light oil cracking = 20:5:17. Building strict ratios at full scale tends to bloat, so in practice, the 8:2:7 approximation becomes more manageable. I frequently base mid-game backbone lines on this approximation. Paired numbers scale and expand cleanly, and when jams appear, identifying "what's short" becomes intuitive. The ratio philosophy itself applies across factory design generally—nothing special about oil.

One clarification: basic oil processing isn't weak. For short-term early-game use, simple structure and fast startup make it genuinely excellent. But once plastic, sulfur, and battery chains ramp, that 9 gas-per-second cushion erodes fast. When expansion feels insufficient, raising the recipe tier rather than adding more lines is the right read. The oil processing overview comes from the Oil processing - Factorio Wiki and similar references.

Oil processing

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Primary Uses of the Three Oil Types (Heavy, Light, Petroleum Gas)

Stabilizing advanced oil processing requires deciding upfront which oil feeds what purpose. Skipping this makes surplus handling priorities undefined. The three types share names but diverge sharply in factory roles.

Heavy oil starts with lubricant production. Lubricant feeds directly into electric engine units, with consequences cascading into roboports and upper-tier logistics. You can decompose heavy oil into light oil, but only heavy yields lubricant, so securing this first is critical. Operationally, routing heavy oil through lubricant chemical plants first, then spilling excess to cracking, stays stable.

Light oil is the fuel workhorse. It pairs especially well with solid fuel. Solid fuel yield favors light oil: 10:1 from light oil, 20:1 directly from heavy, and roughly 13:1 equivalent when heavy is cracked into light first. By ratio alone, centering fuel production on light oil is rational. Once rocket fuel enters the picture, light oil's fuel role grows stronger still.

Petroleum gas is the most versatile oil product. Plastic, sulfur, and batteries—most mid-tier intermediates—concentrate here, so early-to-mid game shortages typically hit petroleum gas first. I used to think "advanced processing still feels tight even now," but it turned out I hadn't properly built heavy and light escape routes. I was accidentally strangling gas production myself. To boost gas output, stop light and heavy from jamming—that's the lever.

The priority ladder, stated plainly: heavy oil feeds lubricant first; light oil covers fuel-tier demand; any surplus splits to petroleum gas. Once that role split clicks, oil lines read much more clearly. Later cracking pump controls and tank thresholds also plug in more smoothly once you've locked down "which oil type survives for what."

Starting with Basic Oil Processing: A Jam-Free Minimal Setup

Aligning Input/Output Positions with ALT Mode

The first move after placing an oil refinery isn't laying pipe—it's using ALT mode to spot input/output positions and aligning crude intake and all outputs to match later scaling. Oil refineries, once recipe is set, show input/output slots in ALT view. Since those positions are fixed, rotating for alignment and pre-staging a placement that supports later side-by-side expansions is crucial. The Oil refinery (input/output positions) specification is your reference.

The goal isn't perfecting your minimal form today; it's laying the foundation to pivot to advanced processing later. Pre-running crude inflow and gas outflow in straight lines makes it far easier to attach chemical plants and water after research. I often position the gas side toward the factory interior and the crude side toward the outside, letting petroleum gas flow directly to plastic and sulfur while heavy/light oil tank off the far side.

Early builders tend to cut corners with diagonal runs and ad-hoc underground pipes. That habit echoes later: when you flip to advanced, light and heavy oil escape routes don't materialize, so you end up demolishing everything anyway. Even in minimal form, leaving one pipe's width of breathing room around the refinery cuts revamp rework substantially.

Oil refinery - Factorio Wiki

wiki.factorio.com

Petroleum Gas Priority in Early Operation

Right after research, the first shortage is almost always petroleum gas. Plastic and sulfur demand spike, but heavy and light oil haven't yet found big consumers. So the minimal setup makes petroleum gas the star and spins the line on that—it jams least. The Oil processing - Factorio Wiki entry documents this halt condition and inter-oil relationships clearly.

Piping logic is simple: crude intake → oil refinery → petroleum gas direct line goes first, feeding that gas straight to chemical plants. Connect either plastic or sulfur, or both, to keep gas flowing. Basic oil processing's single refinery produces 9 gas per second—very practical for post-blue-science startup. Demand direction is clear, so design judgment doesn't waver.

The nasty part: if even one output maxes, the whole refinery halts. I learned this the hard way: I ran gas without receptacles for heavy or light oil, thinking "gas only, so we're safe." Light oil filled first, the refinery stopped, and petroleum gas vanished with it—taking my plastic and blue science down. Oil line peril isn't shortage; it's surplus blocking necessary product.

So early operation demands a reframe: don't consume all three—stage them. Even without full cracking at this stage, just having somewhere for surplus to park keeps gas production alive. Early oil prioritizes stability over efficiency; the farm grows faster.

Temporary Storage and Revamp-Ready Piping

The minimal setup's real form is much simpler than it sounds: feed crude to one line, send petroleum gas directly downstream, and dump heavy and light oil into parallel storage tanks. Storage tanks hold 25,000 units each—huge early buffer. Since oil needs escape routes before consumption endpoints, reserving one or two heavy and light tanks up front anchors stability.

Critically, don't let tanks become endpoints. Leave breathing room before and after so you can later branch into lubricant chemical plants, heavy cracking, light cracking, or solid fuel. Early, tanks are just parking lots. By mid-game, you'll want heavy feeding lubricant and light fueling systems. Tanks pinned against walls kill that expansion room and trigger dreaded revamps.

I often leave one branching point open in tank plumbing. That alone makes later pump control injections or side-spawned chemical plant rows trivial. When advanced kicks in, piping is the luxury—genuine freedom comes from "I left branch room in my straight line." Foresight here dodges rebuilding refineries later.

Simply, the reproducible early-game skeleton is one refinery row, one direct petroleum gas line, parallel heavy/light oil tanks. Polish takes a backseat to "won't jam, upgrades smooth"—and that's where early oil actually wins.

Advanced Oil Processing: Ratios and Recommended Equipment Count

Reading 20:5:17 and 8:2:7

After advancing, the benchmark ratio to anchor on is 20:5:17: oil refinery : heavy oil cracking plant : light oil cracking plant count. If you line up 20 refineries, pair with 5 heavy and 17 light cracking chemical plants, the flow stabilizes. This is a mid-to-late-game classic found across Oil processing - stable wiki references.

Full-scale 20-unit blocks are unwieldy. That's where 8:2:7—a compact approximation of 20:5:17—fits building better. Eight refineries, two heavy crackers, seven light crackers. Not exact, but remainder gets soaked by storage buffer easily. I launch most mid-game lines from this shape.

A table clarifies reading:

The ratio's strength is less the numbers themselves than plugging in only what runs short later. I'll start 8:2:7, secure some lubricant, spin it up, then append identical blocks when light or gas shortages hit. Burning the full 20:5:17 upfront wastes piping restructure; 8:2:7 as a base unit revises cleanly and scales gas without rewiring.

Understanding "19.5 Petroleum Gas Equivalent per Refinery per Second"

When evaluating advanced processing, one refinery's 19.5 petroleum gas equivalent per second is crucial. It's not just the direct gas output—it bakes in the heavy and light oil you crack all the way down to gas (note: some figures here reflect community measurements; for strict accuracy, cross-check Oil processing - Factorio Wiki). Versus basic's 9, advanced's value clicks immediately.

Quick reference:

Internalizing 1, 5, 10 refinery gas outputs lets you split decisions: "More plastic, or secure lubricant, or hold light oil for rockets?" Especially mid-game, hoarding light oil while gas runs short loses to flowing excess into cracking. Factory-wide stability improves.

Heavy oil does prioritize lubricant sometimes; light oil does fuel and rocket duty. Still, one refinery ≈ 19.5 gas equivalent as a design baseline absorbs demand swings powerfully. Ratio design works because of this per-unit conversion.

Expansion and Belt Speed Alignment

Advanced ratios flop into theory because supply planning gets deferred. Petroleum gas pipes fine, but downstream plastic, sulfur, solid fuel flow to belts. Transport belts/Physics/ja gives belt math: yellow is 7.5 items per second single, 15 double sided; red doubles; blue triples.

That knowledge transforms expansion decisions. When you add an 8:2:7 block, do solid fuel and plastic assemble on yellow single-side, dual-side, or red-width mains? I often pre-reserve main trunks at red width—yellow works launch, but red-swapped later lets you double-speed the existing footprint without rerouting.

Speed tiers:

Oil lines hinge as much on which streams convert to items for belting as fluid ratios. Light oil becomes solid fuel (airtight by ratio), doubling as dense fuel backbone. Balancing fuel and gas keeps everything breathing.

Operationally, launch 8:2:7, then append identical blocks as shortfalls show. Fluid side mirrors horizontally; item side swaps yellow→red→blue. One factory never gets torn down.

Transport belts/Physics

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Lubricant Priority and Surplus Cracking Piping

Why Heavy Oil Feeds Lubricant First and Branching Strategy

If you want advanced processing to jam minimally, the design is crystal: heavy oil routes to lubricant first, and only surplus after lubricant demand is met goes to heavy cracking. Since any full output halts the refinery, treating heavy as "spare processing stock" arrives too late—priority must embed in the pipes themselves.

Lubricant locks production because shortfall chokes base expansion visibly. Electric engine units can't progress without it; roboports and upper tiers cascade-stall. I learned this mid-game when boosting heavy cracking to chase petroleum gas while lubricant tanks drained alone. Stopping cracking instantly stabilized the line—heavy oil can't be treated as surplus.

Piping-wise, run a lubricant-direct line from heavy oil output first, then anchor cracking downstream. Fluid ins/outs are fixed, so ALT-checking orientation then setting heavy's shortest path to lubricant locks intent against future tampering. {{ogp:https://wiki.factorio.com/Oil_processing|Oil processing - Factorio Wiki}} validates lubricant's priority through decomposition deferral.

A clean pattern: keep lubricant's throughline always open (bypass-like), enable heavy cracking only when heavy storage tops up. Lubricant stays primary; cracking becomes "cleanup." Ratio math matters second to pump-and-tank ordering.

Light Oil Applications and Gas Conversion Trade-offs

Next question—light oil—uses the same logic: reserve light for future needs, vent current surplus as petroleum gas. Early-to-mid game, gas demand leads, so storing light oil while shortages hit gas weakens the whole factory. Cracking it buys breathing room.

Yet light oil appreciates later. Rocket fuel and solid fuel value light oil—fuel yields are 10:1 from light, 20:1 from heavy, 13:1-equivalent if heavy cracks to light first. So light deserves flexibility—a midway fluid that can gas-shift today and fuel-pivot tomorrow.

This reframes light cracking: don't always crack everything. Run fuel or rocket systems and proportionally reduce cracking. Branch piping—one line to fuel systems (steady open), another to cracking (demand-controlled)—separates concerns and lets you shift light allocation without rebuilding.

Light cracking isn't antagonist; it's intermediate surplus handling and gas stability. Frame it that way, and growth absorbs easily.

Pumps and Tanks: Building "Priority" Into Pipes

Real factories codify priority through tanks and pumps, not ratio charts alone. Fluids level-equalize if just connected, so what fills first and what draws from where must be hard-wired. I set stones: tank → pump → cracker, embedding priority in layout before circuits.

Simplest: put small buffers on light and heavy lines, but only connect crackers downstream through pumps. Tanks absorb swings (25,000 units is huge early), and circuit-wired valve hysteresis—"pump on above 50% tank level"—auto-governs. Even pump-free, up-stream-direct and down-stream-pumped creates mechanical priority.

Light copies verbatim: fuel gets tank-direct, cracking gets pump-gated. Demand shifts then just kill pumps or tune crackers—no replumbing.

Jam-proof oil lines don't consume every drop—they prioritize escape routes in sequence. Heavy→lubricant→stockpile→crack. Light→fuel-future→temp-stock→crack. Clacking becomes insurance, not foundation.

Common Jams and Failure Modes

How One Full Output Halts Everything

The trap most early players hit: even one surplus oil type stops the whole refinery. Oil refineries halt if any output maxes. {{Oil processing - Factorio Wiki|Oil processing}} details this behavior—miss it, and "heavy alone topped out but gas died too" baffles you.

I made that mistake: light filled while I wasn't watching, the refinery froze, and plastic stalled from gas loss, not demand. Oil peril isn't scarcity—it's surplus choking necessary products.

Given that, priority flips: create escape routes for all three before they clog. Heavy and light get tanks; unused tiers get cracking-backup. Tap into that and the "one-jam halts-all" design becomes manageable.

Stalled Fluids and Tank Operations Basics

After advancing, usually only petroleum gas demand immediately matures, leaving heavy and light stranded. The trap: "we'll use it later"—then that orphaned oil fills up and kills everything.

Early practice: call it quits and exhale unused types into storage, then liquidate surplus by cracking. Tanks hold 25,000 units—massive buffer while consumers ramp. They're not luxury storage; they're jam-delay valves buying time.

Use tanks as status lights. Persistently-full heavy tank? Lubricant and cracking both fall short. Rising light tank? Fuel or cracking demand lags. Empty? That oil flows. Fluids hide their blockages, so tanks expose them.

Lubricant Drought Accidents and Prevention by Order

Oil can betray: chase one surplus and starve a dependency. Classic: over-crack heavy for light while lubricant tanks evaporate. Lubricant feeds electric engines directly; stall that and the mid-game chain shatters.

Prevention is piping order over volume. Route heavy's shortest path to lubricant first, then fork cracking behind. Heavy cracking pulls surplus, not primary output. Flip that and lubricant starves.

I spot lubricant failures by electric engine lines stopping while refineries run. Not crude shortage—usually bad heavy routing. Cracking steals faster than lubricant drinks. Reverse pump priority and it stabilizes instantly: piping, not formula, is the governor.

Retooling: Keeping Pipe Positions Aligned

Jumping from basic to advanced often jams because refinery ins/outs are fixed—misaligned placement breaks everything later. Align entries at start; pre-stage side-room for crackers and downstream branching. Misalign now, and revamp cost explodes.

Mess this up, and "swap recipes" becomes "tear it down." Spacing for future crackers, tanks, and main feed lines—even symbolically—lets recipe-swaps slide smooth. I unify all target-function facilities in the same orientation using ALT, reserve branching space, and later cuts vanish.

Worst: gas-only piping ignoring where heavy and light escape. Even if you relocate equipment, the whole skeleton jams. Real trick: leave space for heavy/light outlets from day one. Refinery revamps then become painless recipe flips.

Oil lines blend ratio and layout—aligning direction and position side-by-side.

Space Age: What Changes and Cautions

Research and Input/Output Differences

In Space Age, Advanced oil processing research parameters display differently than vanilla convention. Key insight: this isn't a "completely redesigned minigame"—it's fine-tuning the basic→advanced migration path. {{Advanced oil processing (research) - Factorio Wiki}} shows research intent; design and practical piping can diverge slightly.

My read: Space Age oil design fits best if you launch basic, then iterate toward advanced post-research, parallel to the vanilla spine. Pre-aligned refineries make output-route expansion much easier. Start gas-focused, then thread heavy/light handling in after research—that sequence harmonizes better than trying to hit perfection day-one.

Core lesson persists: basic stability first, advanced expansion next, bottleneck-proof second. Vanilla bones don't snap in Space Age.

Simple Coal Liquefaction and Limits

Space Age adds simple coal liquefaction: invest 25 heavy, 10 coal, 50 steam → yield 90 heavy, 20 light, 10 gas. Make oil without crude—handy when ore thins mid-campaign.

I've used it as auxiliary when a key field stalled, temporarily stabilizing plastic and sulfur. Gas isn't the star (heavy leans harder), but "keep the factory moving" wins mid-crisis.

Numbers reveal character: output skews heavy, light and gas are filler. Try to central-source petroleum gas here and you'll chase heavy disposal instead. Liquefaction shines as contingency cracking partner, not primary. {{Coal liquefaction - Factorio Wiki}} confirms: needs cracking infrastructure to shine.

Design angle: plant coal liquefaction offline as auxiliary feed, route its heavy through existing lubricant-then-crack systems. Normal times, crude backbone runs. Drought phases, coal tops off. Dead simple role split.

Coal liquefaction

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Planetary Elements: Treat as Separate

Space Age's per-planet resource variance and special outputs tilt oil design. But I'll treat planetary conditions as _distinct_ not _extensions_ of vanilla logic. {{Oil processing - Factorio Wiki}} and Space Age - Factorio Wiki share jam-and-priority roots but diverge on supply context. Blending them muddies foundational clarity.

Separate shared design philosophy from planet-specific resource supply. "Keep heavy and light from jamming, route lubricant first"—universal. "This planet has sparse crude but coal-rich"—contextual, not foundational.

I study Space Age oil by anchoring vanilla bone, then overwriting planet quirks. Splits "why oil jams" from "why gas shortfalls happen here," avoiding design-blindspot crossover.

Planets enrich expansion but muddy principles if bundled. Keep vanilla spine front-and-center; planetary variants layer on top cleanly.

Oil processing

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Next Expansion: Solid Fuel, Rocket Fuel, Train Logistics

Solid Fuel

Post light-oil setup, solid fuel becomes your natural next sink. Numbers say it all: 10:1 from light oil (best), 20:1 direct from heavy, or ~13:1 equivalent if heavy cracks to light first. Light-centered fuel is hard to beat. Post-lubricant-reserve heavy oil grows into light-then-fuel chains.

Solid fuel isn't "filler"—each units holds 12 MJ, so it backs up power or steam as auxiliary fuel. Oil gas demand wobbles; solid fuel's a pressure-relief valve. I slot it less for power lead and more as stop-the-refinery insurance, diverting light when gas cracking wavers. Light tank rises? Solid-fuel it. Gas demand climbs? Dial back solid production.

{{Solid fuel - Factorio Wiki}} details specs. Cross-read ratio articles to lock where light fork-splits: how much solid, how much cracking?

Solid fuel - Factorio Wiki

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Light Oil Backbone for Rocket Fuel

Until rocket fuel looms, light oil looks "always surplus." The moment it enters scope, light demand explodes. Scale up and light shrinks fast—suddenly you're short where you were once drowning it in cracking. I learned this painfully: light's narrow mains bottlenecked once rockets kicked in; what worked yesterday failed tomorrow.

Futureproof: pre-size light backbone and reserve branching room for downstream. Rocket won't show immediate need, but it's coming, so size the trunk line for maturity. Separate the heavy→lubricant priority line from a light as star player main. Post-research light cracking, but light itself flows rich to future rocket infrastructure.

Related ratio articles flesh out fuel-demand math.

Train Transport and Barreling Options

Oil products don't need pipe-only supply. Distance and scale suggest short-range pipe, long-range train, early-tier barreling. Trains crush long hauls: fluid wagons hold 50,000 units each. Landing pads take two tanks per wagon, making station math clean. Distant fields? Pipe crude locally, train refined product, rebuild without long-distance pipework. Simpler and expands easier.

Offload speed is snappy: pumps theoretically max ~1,200 units/sec, up to three per wagon—~14 sec per wagon refill or drain, ideal. Trains feel less "slow supply" and more "bulk handoff per station." Long-distance oil main becomes "route to stations" instead of "extend forever."

Barreling still works early: 50 units per barrel is fine for droplet transfers or pre-fluid-wagon eras. Once volume climbs, barrel logistics (stuffing, recycling, routing empties) burn effort faster than wagon ops. I treat barreling as placeholder until trains scale, not permanent.

Design-wise: supply method matters alongside production ratio. Light-main undersizing then late rocket-demand panic taught me this. Decide where and how before locking ratios. Distant oil? Train planning first, pipe ratios second. Colocated? Pipe mains, but reserve train backup space.

Each choice reshapes how oil distribution supports downstream chains. Ignore it and you're retrofitting under pressure.

Summary

Oil lines stabilize when launched basic with tanks, then early-transition to advanced. Operational spine is unwavering: heavy oil feeds lubricant first; surplus splits to cracking. This protects necessities while preventing halts.

Design prizes building in increments over perfect scale. One output jamming halts everything, so tank-and-pump sequencing beats pipe diameter. Treat each ratio block as a growth unit—expand by units, keep tank buffers, let cracking be insurance.

From there, sharpen light into fuel chains, run solid fuel, and pick trains for long distance. I treat oil as tomorrow-ready bone, not today's ceiling, and future scaling becomes trivial.

• Ratio Calculation Guide (detailed oil-line ratio math)
• Transport Belt Fundamentals (belt speeds and throughput)