Editing 40d:Screw pump

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Salt water pumped through a pump will become drinkable if then kept separate from natural walls, natural floors, other salt water or an aquifer.

 

''For a basic overview of how the different machine parts work and work together, see [[machinery]].''

It's important to choose the proper orientation for your pump, where it will draw water from and where it will deliver the water.  This is determined before placement with the {{k|u}}, {{k|k}}, {{k|m}}, or {{k|h}} keys, and the text at the top of the sub-menu will change to confirm your choice.  The default (as shown above in the sidebar), "pumps from the north" (top).  The ''light'' green X must be next to the liquid source and the ''dark'' green X is where the liquid exits the pump. [[Image:Small pump.jpg|thumb|right|300px|'''Basic Side View of a Pump'''. <br /> This pump "pumps from the west", from left to right.  The area to the right may fill to the top of that level, but no more  (See [[pressure]]; see [[Screw_pump#Pumping_up_multiple_levels|Pump stack]]). Note that the entire space required is 4 tiles long by 1 tile wide, not including any retaining walls for the outflow.  If pumped manually, the [[pump operator]] stands in the light-colored area, as the dark-colored is impassable to both fluid and movement.<br />

This example "pumps from the west" (left) to the east (right), the {{k|h}} option.  If pumped manually, the dwarf stands on the light-colored tile, as the dark-colored is impassable.

* The source of the pump must be directionally adjacent to "Open Space" that is directly above a source of liquid. The adjacent space cannot be a floor, stairway or wall suspended over water. Screw pumps can pull water through a grate, floor bars, or a [[construction|constructed]] fortification on the Z-level below.

* Adjacent pumps ''automatically'' transfer mechanical power to any other adjacent pump(s), no [[axle]] or [[mechanism]] is required.  If too many pumps are adjacent, there may be insufficient power to run them. This does '''not''' apply to pumps being manually operated by dwarves.

* In order to build pumps in a "hanging" state, as in the stacked screw pump example (below), one of its tiles must be able to connect to a nearby machine, either already existing or designated to be built. If, when the screw pump's construction is completed, the supporting mechanism has not yet been completed, it will promptly collapse into its component parts.

* In order to safely pump magma, the pump must be made of [[magma-safe]] materials or the pump's components will melt or burn. Curiously, if the [[pipe segment]] is made of any [[metal]], then none of the pump's components will heat up, allowing a wooden corkscrew to pump magma without problems. This is likely a bug.

* Magma, which normally has no pressure, will behave like pressurized when pumped. For example, when pumped into an U-turn, magma will come out at the other end. Normal (non-pumped) magma would just pool at the lowest level. This may be either very useful (can be used to build pressure towers for magma) or deadly (forge level flooded with magma, because someone tried to pump magma into a volcano).

* Pump's pseudo-pressure doesn't work across diagonals. If there is a diagonal-only passage in your tunnel, liquids will seep slowly through it, instead of bursting through above their normal maximal speed, like they would if there was good passage.

The easiest way to do this is to stack the pumps directly on top of each other in alternating directions, also known as a '''pump stack'''. The first one pumps North to South, the one directly above it pumps South to North, the next one above that pumps North to South again, ad infinitum. Make sure to fully surround the area the water will fill with walls, including diagonals, or water will leak out very fast.

Adjacent pumps automatically transmit mechanical power. If the pumps are "open" (that is, built on channeled tiles) to each other across z-levels, then a stack only requires (sufficient) power to be transferred to one pump. All others will be powered by association with the first. You can transmit power to each pump by simply channeling out the floor at the front (aka output side).

:#Solution for a freestanding tower - fire escape! You can also consolidate the up and downstairs into a single up/down stair tile. Just build these on top of each other, flipping horizontally each time. Minimal yet aesthetic multi-level water pumping.

# In this example the power is brought back up to the surface for pumping straight from a river. To do this, dig away from the first gear until the surface is clear above. Place another gear here.

It is recommended that you connect a lever to one of your gears beforehand. The pump will start pumping as soon as it has power.

[[Image:Screwpump-desalination.png|thumb|An example of how to desalinate water. Single-tilde water is salty, double-tilde water is pure.  Constructed walls and floor are not shown.]]

Screw pumps also act to desalinate any water which is pumped through them. This is very useful for providing a source of potable water in otherwise entirely salt-water regions. However, if desalinated water comes into contact with natural walls or natural floors, other saltwater, or passes through a saltwater [[aquifer]] level (even if that has been sealed by [[smoothing]]), the water will be ''re''salinated.  So any freshwater cistern (tanks) must be entirely constructed to the full level of the water, with no natural floors or walls that will come in contact with the de-salinated water.

{{Category|Machine components}}