Sandustry Fluid Logistics: Pump, Pipe and Liquid Vent Guide

Understand the machine's job before placing it

Fluid logistics is a three-part system: a Pump collects liquid, Pipes connect the network on their separate layer, and Liquid Vents release the stored mixture. Diagnose the parts in that order. A visible pipe line says nothing about whether the intake is submerged or the vent has room.

Crossing Pipes merge into one network, and all liquids in that network mix and distribute. Use physically separate networks when two fluids must remain distinct. A drawing that shows two colored lines crossing is not two isolated routes in the game's pipe layer.

Follow the documented input and output rules

The official Pump page states that every pixel can act as an intake and that a fully submerged Pump can move up to 16 pixels per tick. Solids inside the Pump block intake. Lava is not supported. These constraints make clean intake chambers and material screening essential.

The official Liquid Vent page documents a maximum of 4 pixels per tick and says output stops when the vent is about three-quarters submerged. Under otherwise clear conditions, one 16-per-tick Pump can feed four 4-per-tick vents. That is a capacity ceiling, not a guarantee when immersion, blockage, or network demand differs.

Build a serviceable layout

Build a clean source pocket around the Pump, route Pipes without crossing unrelated networks, and place Vents where discharged liquid can move away. Provide four vents only when the source can keep the Pump submerged and each destination remains below the stop level.

Add a shutoff or removable connection near the source and leave access to every vent. If the network carries more than one liquid, label that choice as intentional. Otherwise isolate networks before the crossing and test each with a small amount to confirm there is no hidden merge.

Measure sustainable throughput

Treat Pump, Pipe, and Liquid Vent network as one boundary in a longer chain. Start with empty or recorded buffers, count how much a supported liquid touching a Pump reaches the input during a fixed interval, and compare that with the mixed network liquid through one or more Liquid Vents leaving the output. Record material still inside the chamber. A growing reserve before the machine identifies an intake or processing limit; a growing reserve after it identifies a collection or destination limit.

Do not infer an exact rate from a short animation. Let startup material clear, repeat the interval, and test again after saving and loading. If supply arrives in bursts, record both average flow and the largest burst. Add parallel capacity only after the same boundary limits two clean observations. Otherwise extra machines can hide a routing fault while consuming space, power, heat, cold, or scarce construction resources.

Diagnose the first failed boundary

When intake is slow, inspect Pump submersion and remove solids from its cells. When one vent stops, check local liquid depth before blaming the whole network. When every vent stops, compare source availability, Pipe continuity, and whether an unintended crossing distributed liquid elsewhere.

If the wrong liquid appears, trace all Pipe crossings and connected Pumps. The network mixes its contents; waiting will not separate them. Isolate the source, drain the contaminated network into a safe area, and rebuild distinct routes before restoring production.

Apply the v0.5.6 version notes

The cited official pages provide the current capacity and mixing rules used here. Update #3 changes Lava density and destruction but does not make Lava pumpable; the Pump page still says it cannot pump Lava. Keep Lava on a separate documented conversion or containment route.

Retest modded fluid networks on the v0.5.6 mods branch. New building-removal and material events can affect custom components, and a mod may introduce its own capacity or supported fluid. Preserve vanilla figures as the comparison rather than treating a modded result as a base-game update.

Validate the design in a small test cell

Build one isolated Pump, Pipe, and Liquid Vent network with a limited input sample, visible output pocket, and a way to stop supply. Label the game version and active mods. Observe the expected transformation, any byproduct, where each pixel settles, and what happens when the destination fills. Then clear the cell and reverse the loading order if two materials share space. A repeatable small test gives a stronger design basis than a screenshot of a large factory.

After the test passes, copy the geometry into production while keeping access to the input, output, and removal controls. Leave enough room to inspect or drain the machine without opening a neighboring line. Recheck the route after patches that mention the machine, its materials, density, heat, fluids, energy, or building events. Keep the prior measurement with its version so a future change is visible instead of becoming an unexplained slowdown.

Use the pre-launch checklist

Before opening full supply, confirm that the input really is a supported liquid touching a Pump, the planned result is the mixed network liquid through one or more Liquid Vents, every required power or temperature connection is active, and no incompatible material can enter. Verify output clearance, overflow capacity, a shutoff point, and a safe path for the player. Take one recovery save before connecting a rare or destructive input.

During the first long run, compare starting and ending inventory at every boundary. Watch for material trapped inside building cells, a mixed network, a full destination, and a reserve that only delays failure. If the line remains balanced through its normal burst and restart conditions, record the observed rate and promote the module as the factory's current versioned standard.

Field facts

Troubleshooting

• Pump intake drops.

  Increase supported-liquid contact around the Pump and clear solids occupying its intake pixels.

• A Liquid Vent stops while the network is supplied.

  Check whether the vent is about three-quarters submerged and clear its destination.

• Two liquids unexpectedly mix.

  Find a Pipe crossing or shared connection, isolate the sources, drain the network, and rebuild separate routes.