Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Chromie]

I'm starting up a obsidian-pouring project. So I've got a pump stack for magma going from the bottom of the map to the surface, right now, all green glass pieces.

They're not pumping anything, they're not 'running dry', the power is disengaged. There are no berzerk dwarves or buildingdestroyers around. But my empty pumps are spontaneously deconstructing. What the hell?

[kcwong]

I'm starting up a obsidian-pouring project. So I've got a pump stack for magma going from the bottom of the map to the surface, right now, all green glass pieces.

They're not pumping anything, they're not 'running dry', the power is disengaged. There are no berzerk dwarves or buildingdestroyers around. But my empty pumps are spontaneously deconstructing. What the hell?

It would help if you upload your save somewhere so we can look at it.

But from "power is disengaged" and "spontaneously desconstructing" it sounds like your pumps are hanging on a gear which you removed with a lever...

http://dwarffortresswiki.net/index.php/Gear
See if the section "Disconnected gears" describes what you've constructed.

[Akigagak]

Or; YOUR PUMPS ARE MELTING.
Glass doesn't like magma.
Go for steel/iron.

[Quietust]

Or; YOUR PUMPS ARE MELTING.
Glass doesn't like magma.
Go for steel/iron.

It's been demonstrated in a forum thread that screw pipes made entire from glass are, for some reason, magma-proof.

[Akigagak]

What? How bizarre.

[Dorf3000]

Do you have something like this on the lowest z-level?:

_pump_ |
##########
is there a clear space behind your pump that leads directly over a magma source tile?
Because the source will try to fill the empty space above it, flow onto your pump and melt it.

You would need to do something like this:
_pump |
#####_####

so the pump level can't be filled by the source.

[Shurhaian]

Wrong. Magma doesn't flow upwards like that. Only if there's a gap from above or the sides will it flow in and hit the pump.

Depending on how exactly the pumps are rigged... "disengaged" could be the problem. If you have them shut off, and they're "hanging" on the gear assembly that's disengaged, that would make the whole system collapse.

(I can personally vouch for the magma safe materials not being the issue. It's been suggested that WOODEN parts will eventually scorch from the heat on either side, but it doesn't actually behave like the magma is going through the pump. Fire-safe materials seem to suffice.)

[Dorf3000]

Wrong. Magma doesn't flow upwards like that. Only if there's a gap from above or the sides will it flow in and hit the pump.

That's why I said magma SOURCE tile.  They do in fact create magma above them if there's a space, and its the only way magma rises without a pump.

And AFAIK there's no way to build a pump without the walkable tile being on solid ground, so that rules out any gear disengaging shenanigans.

[Jim Groovester]

(I can personally vouch for the magma safe materials not being the issue. It's been suggested that WOODEN parts will eventually scorch from the heat on either side, but it doesn't actually behave like the magma is going through the pump. Fire-safe materials seem to suffice.)

I've had wooden pumps not deconstruct in magma. I've also had them ignite. Outside temperature seems to be a factor. Hotter biomes tend to ignite wooden pumps, colder ones tend to keep them around. Something to keep in mind when you need to melt some ice to get water on a glacier, that a wooden pump will probably do the job just fine and won't ignite in the process.

Anyways, if you're building lots and lots of screw pumps at once, it might take some time to get them built, and they can deconstruct if your mechanics and architects and carpenters and masons take too long to build your pump tower. Are you certain that all your pump tower was built within the frame of time it takes before pumps start deconstructing? That could be the problem.

[Albedo]

<nods>

There's more going on than a simple "A works, B doesn't".  DF is like that, again and again.

For example, sometimes fire imp fat burns and burns, and sometimes it explodes.  The diff seems to be map dependent.  (I have a growing suspicion Toady has modeled heat and temperature very complexly, just for his own amusement.)

It's possible that the ambient heat is too much for (some of) the glass parts. Possible.  Try again with stone blocks, and hope for the best.

Because the source will try to fill the empty space above it, flow onto your pump and melt it.

Magma flowing naturally does not flow up like that.  If it's been previously pumped it can, and water will.

What? How bizarre.

As bizarre as someone taking a completely blind guess and stating it as fact?

I made the same mistake - DF and "logic" or "common sense" do not go together.  Again and again... 

[Chromie]

I fixed it, I didn't realize that disengaging the gear assembly (to turn on/off the pumpage) removed 'support' from the pump stack. They were completed in a wonky order so when a completed pump was finished over an only-designated pump that now no longer had even imaginary support, it had an existential crisis and crumbled.

My pumps DID melt but this was a problem regarding backwash once my magma mold was filled.

[random51]

Instead of using a gear, use a hatch over the tile the bottommost pump pumps magma from.  Want to turn off the lava, just close the hatch.  Works great and you can close it if you've got dwarf morale issues.

[Albedo]

My pumps DID melt but this was a problem regarding backwash once my magma mold was filled.

Most things will "melt" when submerged in magma.  This is not the same as being "in contact with" magma.  Stone doors, for instance, will work fine while shut against a wall of magma, and if the magma goes away (or is turned to obsidian, etc) they'll open fine.  But if opened while magma is there, they're toast, they either melt or deconstruct, or both.

[Puzzlemaker]

Screwpumps can be a little screwy.

[torne]

Because the source will try to fill the empty space above it, flow onto your pump and melt it.

Magma flowing naturally does not flow up like that.  If it's been previously pumped it can, and water will.

No, Dorf3000 is right: if you dig far enough (horizontally) into the pipe that there is empty space above one of the magma SOURCE tiles on the very bottom Z-level then magma will eventually spawn inside that empty space, which will then flow horizontally onto the walkable tile of the pump and melt it unless it's made of magma safe materials. Magma source tiles spawn little columns of magma at the current magma surface level above the tile, up to the original level of the pipe. I have flooded my pumping operations with magma this way