Fluid system
Fluids are non-solid items, such as water and oil.
Mechanics
Fluids can only exist inside pipes and certain buildings, meaning they cannot be carried by the player, moved using inserters, dropped on the ground, or even dumped in a lake. They are counted in continuous fractions, rather than discrete integers. Liquids can be silently destroyed by removing buildings or pipes. Only one type of fluid can occupy a pipe at a time. Two fluids will never mix.
Fluids can be transported by piping, barrels, or fluid wagons.
Pressure
Here "pressure" = current_fluid_level / max_amount.
The pressure of a fluid in a pipe can be seen through the pipe window. A pipe with high pressure will show itself nearly full, a pipe with low pressure will show a small trickle of the fluid.
When two neighboring containers (pipes or fluid storage) store the same fluid at different pressure, some of the content of the fuller container will move into the less filled one. The speed of this transfer depends on the difference in pressure.
Fluids do not flow out of a building's input tile or into its output tile. Pumps partially override pressure, putting all their content into their output tile.
Volume
In the game, fluid is held in fluid boxes with a defined size (equivalent to volume). Connected fluidboxes allow fluids to flow between them. For instance, each pipe is a 1x1 fluid box with a connection in each direction.
The volume of fluid contained in a fluid box is value between 0 and the fluidbox size, so for instance the pipe can hold 100 Units of fluid, so the value in the fluid box can be any number between 0 and 100.
Temperature
Work contained in fuel is converted by the boilers or heat exchangers to steam, which is just a liquid form of work. This steam holds energy at ratio of
0.2 kJ per °C per Unit
In other words: 0.2 kJ of work is necessary to heat water by one °C.
Since steam/water is set to have a maximum temperature of 500°C and minimum of 15°C, the most work that can be in an unit of water is 97 kJ.
Types
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Can be extracted from water using the offshore pump. |
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Water heated in a boiler or heat exchanger. Mainly used to produce power. |
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Extracted from oil fields by Pumpjacks and can be converted to Petroleum Gas, Light Oil, and Heavy Oil. |
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Converted from Crude Oil. Used to create various items. |
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Converted from Crude Oil. Used to create various items. Can be converted into Petroleum Gas. |
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Converted from Crude Oil. Can be converted to Light Oil and Lubricant. |
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Converted from Sulfur, Iron Plates, and Water. Can be used to create various items. |
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Converted from Heavy Oil. Used mainly to create Express transport belts and Engines. |
Machines
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Converts Crude oil into Heavy oil, Light oil, and Petroleum gas. |
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Changes liquid to other forms as well as crafting some recipes that require liquids. |
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Extracts Crude oil from Oil fields. |
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Creates 165°C steam when fueled. |
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Creates 500°C steam when heated using a nuclear reactor. |
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Uses steam to generate electricity. |
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Uses steam to generate electricity. |
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Puts liquids into or out of barrels. |
Piping
Piping is the most common way to move liquids in factorio.
Key entities used in piping and general fluid handling:
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Used to direct the flow of liquids. |
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Used to cross other pipes or belts. |
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Stores liquids for later use. |
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Provides Water extracted from a water tile. |
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Moves fluids in the direction of the arrow. Prevents fluid from moving in the opposite deirection. |
History
Water was the first fluid to be added to the game. In version 0.9 the oil processing system, and therefore new fluids, including crude oil and petroleum gas, were added.