Author Topic: Space Industrial Operations: Welding in Space  (Read 34361 times)

Offline TyMoore

  • Veteran
  • Full Member
  • ****
  • Posts: 478
  • Eureka, CA, USA
  • Liked: 3
  • Likes Given: 1
Space Industrial Operations: Welding in Space
« on: 10/07/2006 03:45 am »
So much of what has been discussed on this website involves propulsion, energy production systems, life support, and radiation mitigation, however little has been said (atleast that I can find) about basic industrial processes which will be useful in the space environment. Periodically I would like to explore various industrial processes which may prove useful in space.

Among these is arc welding which has so far been explored a little by the Russians onboard one of the Salyut space stations back in early seventies, I think. Apparently they tried some GTAW (gaseous tungsten arc welding) and Electron beam welding experiments: the amassed enough information to publish a book which I have been unable to locate. Several small Shuttle Getaway Specials were performed to look at arc welding in the space environment, but results have been difficult to come by.

What issues could we expect to confront in welding in space or vacuum; zero g or low-g situations?

   Obviously because of the vacuum it would seem straight 'stick' welding might be the most favorable form of welding—however, how difficult is it to 'strike and arc' in hard vacuum? To ignite an arc, will some carrier gas like argon with a tad bit of neon be necessary to establish an arc, or can simply 'slapping' the electrode against the 'work' be enough to vaporize enough metal to establish an arc?

   Welder design: conventional earth bound industrial arc welders (such as a Lincoln or Miller portable welder) typically either use a 20 hp gasoline or diesel engine to drive a specially wound generator to provide the 10 KW of 20-30vac at 300-400 amps for the welding arc. Air is used to cool the windings in the generator. Obviously in space something different must be used: assuming of course we have enough 'station' power available, what would the design of the unit look like? Might it use a solid state inverter, transformer setup to convert high voltage DC to low voltage AC for welding? Or would it be better to use a dynamotor to convert DC into low voltage AC using a motor generator setup? To minimize or neutralize transient torques from startup, spin down and operational transients of a space arc welder, will it then be necessary to use two mechanically coupled but counter rotating motor/generator units, to minimize torque transients? What about cooling? Using a pressurized case with something like nitrogen blown through the electrical and mechanical parts, and then chilled by a vapor compression freon loop coupled to an external radiator could do the job, certainly, but how big of a radiator do you need? Could you do the same cooling job passively using an ammonia “heat pipe” and condensing radiator?

What about splatter of liquid metal from the work area? Do you need to design a spacesuit 'overall' and bib that protects it from molten splatter? Or do you weld in a vacuum version of a 'glove box?' What about a welding visor for space suits—do you need one externally, or will you just end up needing a specially designed space suit just for welding operations?

These are just some of the questions I'd like to explore:
Is welding practical in space? Are there alternatives? What kinds of special safety precautions would astronaut welders need to follow on orbital or lunar welding operations? Does the lack of gravity and air make a huge difference in the theory and operation of arc welding?What kinds of systems are needed to make welding practical in zero-g and vacuum? Will welding be practical in the low CO2 pressure of Mars' atmosphere? And here's another one: will the welds hold up well to atomic oxygen bombardment from low earth orbit positions, or will special coatings like gold need to be applied?

What do you think?

Offline mauk2

  • Veteran
  • Full Member
  • *
  • Posts: 106
  • Liked: 0
  • Likes Given: 0
Re: Space Industrial Operations: Welding in Space
« Reply #1 on: 10/10/2006 10:52 pm »
Well, if nobody else will comment, I guess I will. :)

This is an excellent thread.  Unlike the fun zoomy stuff, boring mundane crap like running a good bead is what will be required to exploit space resources in a real way.  Sadly, most welding techniques are not well suited to space travel.  (Do YOU want to fly with an acetylene tank?  Think carefully....)

I can think of only two welding techniques that are well suited for vacuum and microgravity/low gravity conditions.  The first is electron beam welding:

http://www.weldingengineer.com/1%20Electron%20Beam.htm

EB welding is a nice process, and best of all, requires only an electron gun and a source of electricity.  LOTS of electricity.  :)  It can weld massive thicknesses, and if carefully done doesn't even need a welding rod.  It actually works BEST in a vacuum, which is a plus, and debris/splatter is minimal and easily contained with a hooded tool.


The other process is stir welding, or friction stir welding.  This is an awesome process that is a tad cumbersome, perhaps, but is almost perfect for space applications.  There is no splatter, it is utterly insensitive to the atmosphere or lack thereof, and can weld thick or thin pieces at excellent production rates.

http://www.msm.cam.ac.uk/phase-trans/2003/FSW/aaa.html

FSW is a classic example of "brute force leads to simplicity."  :)

Some smart cookies at NASA also seem to think this is a winner, as noted here:

http://techtran.msfc.nasa.gov/Patents/(54).html

Hope that helps!  :)

Offline meiza

  • Expert
  • Senior Member
  • *****
  • Posts: 3067
  • Where Be Dragons
  • Liked: 5
  • Likes Given: 3
Re: Space Industrial Operations: Welding in Space
« Reply #2 on: 10/11/2006 12:08 am »
It's hard to do friction stir welding everywhere if it requires an industrial robot, thin surfaces reached from both sides and leaves a hole somewhere. But it's great for making aluminium rocket tanks out of sheets!
If nobody wants to follow the links, it's basically a round stick that is poked into a seam between two plates and when the stick is rotated and some pressure applied to the area from above, the plates can be stirred together, the aluminium becomes soft but does not melt, and thus gives good properties for the finish. Also no gases or liquids or weld materials are needed, making it clean and nice.

Offline hop

  • Senior Member
  • *****
  • Posts: 3352
  • Liked: 553
  • Likes Given: 891
RE: Space Industrial Operations: Welding in Space
« Reply #3 on: 10/11/2006 01:57 am »
Quote
TyMoore - 6/10/2006  8:28 PM
What about splatter of liquid metal from the work area? Do you need to design a spacesuit 'overall' and bib that protects it from molten splatter? Or do you weld in a vacuum version of a 'glove box?' What about a welding visor for space suits—do you need one externally, or will you just end up needing a specially designed space suit just for welding operations?
I would expect a space suit to offer good protection from spatter. The outer layers are coated fiberglass cloth AFAIK, which should compare favorably to the cotton jeans/jacket that are widely found to be sufficient on earth. However, you probably would want a cheap, easy to replace outer layer just to preserve the expensive bits. This should include outer gloves, something covering the front of your suit, and a disposable outer visor. You also have to think about accidental contact with the workpiece, which IMO is a larger safety risk than spatter. From personal experience, by the time you notice your glove is hot, just stoping whatever stupid thing you are doing isn't going to keep you from getting burned. On earth, you take the glove off (or better yet, you notice it smoking before it gets hot). In space, you really want to avoid that :) If you've watched EVA footage, you know that just keeping from bumping into stuff is fairly challenging unless you are well secured.

Auto darkening welding visors are an off the shelf item, and would be the obvious choice for any kind of arc welding. How you integrate this with an exiting helmet should be a fairly minor detail.

Regarding the issues of liquid metals in zero G, there have been a number of experiments on soldering in space (and ISTR some non-experimental soldering on Mir.) All these were done indoors AFAIK, which brings up the point that you will most likely need to weld both inside and outside, and the issues will be somewhat different.

I suspect zero-g has a significant impact on the results of traditional welding techniques, since fluids will behave differently. OTOH, you will never have to do out of position welding (upside down or on a vertical face, both of which are a royal pain).

EB welding obviously benefits from a vacuum, but it produces enough X-rays that it may be a problem for humans at the worksite. Laser welding can produce similar results in many cases, and shouldn't suffer any problems from zero G or vacuum. The equipment isn't normally designed for manual operation, but there isn't any inherent reason it couldn't be. FSW is significantly more cumbersome, and also has trouble with harder metals.

Hard vacuum will simplify many welding processes, since preventing oxidation is a major factor on earth. OTOH, arc and heat transfer characteristics are going to be significantly affected as well.

edit:
Spatter presents another problem, since it will cause bits of conductive debris to go floating all over the place. However, the most spatter intensive processes  usually involve solid flux to prevent oxidation, or impurities in the materials. Cutting might might be a problem.

Offline TyMoore

  • Veteran
  • Full Member
  • ****
  • Posts: 478
  • Eureka, CA, USA
  • Liked: 3
  • Likes Given: 1
Re: Space Industrial Operations: Welding in Space
« Reply #4 on: 10/11/2006 02:07 am »
Friction stir welding is interesting--but the applied forces are pretty large. Torque and hammer-and-anvil forces are pretty large, as well as the translation force. Not all welds are directly applicable to friction stir welding, but certainly many that involve long circumference and longitudinal welds--almost perfect for manufacturing pressure vessels--can be accomplished by friction stir welding. The final 'hole' can be removed by translating completely through the plate, and then patching with a plug. Typically this 'defect' is simply milled away in preperation for butt welding of the next piece. Vacuum is almost perfect for this, I suppose. But friction stir welding is not really something that a person in a suit could do--it can only be accomplished by using a machine.

Electron beam welding in space is another good idea, except that there is always hard x-rays generated from the electrons that penetrate into the interior electron orbitals of iron, nickel, and especially high-Z metals like tungsten. I'm not so sure about aluminum, but titanium probably will also have this probem. Again, no big deal if remotely operated machines do the work, but it can't be done by someone there. Massive slabs can be cut and welded using electron beam welding and cutting--which is why I'm interested in using it for another application: quarrying single slabs of asteroidal nickel-iron--high power electron beams are almost ideal for such an application...

Oxy-acetylene or oxy-hydrogen welding and cutting operations could probably also be done in vacuum--although the welds will still suffer from porosities generated by the combusting gasses, and things like aluminum cannot be welded at all because the work material has a higher affinity for the oxygen than does the fuel.  Still it is interesting to think of other things that could be done with a gas welder-cutter in space...

This leads me to think that wire fed MIG (metal inert gas) or just straight stick welding may be good options for space repairs, patching, and attaching fixtures to structures. Complex welding operations for large, massive parts would still suffer from the need to preheat work before and after welding operations to reduce stresses in the material. This is where friction stir welding may be employed...

Thanks for the feed back. It's interesting to think what it would take to create something like a portable welder for space operations--I'm sure it would end up bulkier, more complex, and a lot more expensive that its ground based counterparts. The only question I suppose would be is it practical? Could adhesives do the same job, or at some point
are you just going to need a good welder?

Hop: Thanks for the feedback--excellent points about the 'thermal lag time.' By the time you feel the warmth of the glove--it's integrity has probably already been comprimised.  I guess we'd have to add some thermal imaging heads-up display in the suit's helmet to find the parts that are really hot--good safety point.

Another good point about laser welding--there are currently some interesting contendors right now for this job such as the water cooled Sony SLD432S4 and the SLD433S4 laser diode arrays. These are laser modules about the same size as a pack of cigarettes that are capable of 1KW of light output using 46vdc@53A, check it out at:

http://www.sony.net/Products/SC-HP/cx_news/vol42/featuring_laser.html

Several of these modules, optically linked and properly phased could easily provide the raw power to cut through steel plate--and robotic and optical systems exist today that could easily lend themselves space operations.

Good points about the disposable face shield--I think even the pro-welders use something similar on their face shields to protect the window from scratches--a thin disposable plastic film ought to do nicely.  Also the auto-transition or auto darkening lense has been in use for some time. Checking my Northern Tool and Equipment catalog, I see that they have autodarkening welding shields from about $150--almost identical technology could be developed for space suits, I'd imagine...

Splatter from welding and cutting operations could probably be mitigated by a Kevlar-Nomex 'Tent' surrounding the work area--reducing or elminating yet another source for annoying artificial MMOD hazards.

Offline space_man

  • Full Member
  • *
  • Posts: 139
  • Liked: 0
  • Likes Given: 0
Re: Space Industrial Operations: Welding in Space
« Reply #5 on: 04/21/2009 03:28 pm »
I found an interesting idea that has not been thought of for welding in space - Newtons second law.

A hot gas welding apparatus used in space will have a micro-nozzle, facing the exact opposite direcrtion of the arch vector, which will provide a constant counter thrust. Otherwise, the welder and the gun will simply fly away from the work area into space.

Offline mlorrey

  • Member
  • Senior Member
  • *****
  • Posts: 2173
  • International Spaceflight Museum
  • Grantham, NH
  • Liked: 23
  • Likes Given: 5
Re: Space Industrial Operations: Welding in Space
« Reply #6 on: 04/22/2009 12:25 am »
Well, if nobody else will comment, I guess I will. :)

This is an excellent thread.  Unlike the fun zoomy stuff, boring mundane crap like running a good bead is what will be required to exploit space resources in a real way.  Sadly, most welding techniques are not well suited to space travel.  (Do YOU want to fly with an acetylene tank?  Think carefully....)

I can think of only two welding techniques that are well suited for vacuum and microgravity/low gravity conditions.  The first is electron beam welding:

http://www.weldingengineer.com/1%20Electron%20Beam.htm
....

You kinda left out ARC, Mig and Tig welding, all of which are fine in vacuum. In fact they should work better in space. The only unique equipment you are going to need is a magnetic device to grab slag spall, otherwise you create a lot of space junk issues.
« Last Edit: 04/22/2009 12:28 am by mlorrey »
VP of International Spaceflight Museum - http://ismuseum.org
Founder, Lorrey Aerospace, B&T Holdings, ACE Exchange, and Hypersonic Systems. Currently I am a venture recruiter for Family Office Venture Capital.

Offline mlorrey

  • Member
  • Senior Member
  • *****
  • Posts: 2173
  • International Spaceflight Museum
  • Grantham, NH
  • Liked: 23
  • Likes Given: 5
Re: Space Industrial Operations: Welding in Space
« Reply #7 on: 04/22/2009 12:30 am »
I found an interesting idea that has not been thought of for welding in space - Newtons second law.

A hot gas welding apparatus used in space will have a micro-nozzle, facing the exact opposite direcrtion of the arch vector, which will provide a constant counter thrust. Otherwise, the welder and the gun will simply fly away from the work area into space.

Its been thought of, and is why oxy-acetylene welding is not viable in space.
VP of International Spaceflight Museum - http://ismuseum.org
Founder, Lorrey Aerospace, B&T Holdings, ACE Exchange, and Hypersonic Systems. Currently I am a venture recruiter for Family Office Venture Capital.

Offline GI-Thruster

  • Full Member
  • ****
  • Posts: 732
  • Liked: 4
  • Likes Given: 0
Re: Space Industrial Operations: Welding in Space
« Reply #8 on: 04/23/2009 04:50 pm »

Another good point about laser welding--there are currently some interesting contendors right now for this job such as the water cooled Sony SLD432S4 and the SLD433S4 laser diode arrays. These are laser modules about the same size as a pack of cigarettes that are capable of 1KW of light output using 46vdc@53A, check it out at:

http://www.sony.net/Products/SC-HP/cx_news/vol42/featuring_laser.html

Several of these modules, optically linked and properly phased could easily provide the raw power to cut through steel plate--and robotic and optical systems exist today that could easily lend themselves space operations.


The link says they have optical power density of 211 W/cm^2.  What sort of power density would one need to cut steel?  Do you see a limit as to how many of these can be stacked?  Is there an industrial standard for working laser rifles?  :-)

The reason I ask is I'm also interested in developing mining tools for space.  An electron beam might make a nice knife but there are those x-rays.  If EEStor delivers what it says it will, then their next gen BaTiO3 caps could store enough energy to make 10 kW lasers light and portable.  They wouldn't be able to run long without a generator hooked to them, but a welding/cutting tool that is both connected to a generator for extended use, and also can go cordless when needed; would be a great tool for mining, construction, etc. and the nice thing about caps is they can be recharged very quickly.

Offline hop

  • Senior Member
  • *****
  • Posts: 3352
  • Liked: 553
  • Likes Given: 891
Re: Space Industrial Operations: Welding in Space
« Reply #9 on: 04/25/2009 06:13 am »
I found an interesting idea that has not been thought of for welding in space - Newtons second law.

A hot gas welding apparatus used in space will have a micro-nozzle, facing the exact opposite direcrtion of the arch vector, which will provide a constant counter thrust. Otherwise, the welder and the gun will simply fly away from the work area into space.
Its been thought of, and is why oxy-acetylene welding is not viable in space.
Uh, no. Figure out how much thrust it actually generates. Hint: If you weld on earth, you have to hold the torch up against gravity, and turning it on and lighting it doesn't significantly reduce this effort.

Astronauts on EVA are affected by all kinds of forces, that's why they use tethers, hand rails, foot restraints etc. A few ounces of thrust from a torch would be nothing compared to things they already do routinely... like bashing stuff with hammers.

None of this is to say that that combustion based welding would be a good choice.
Quote
You kinda left out ARC, Mig and Tig welding, all of which are fine in vacuum. In fact they should work better in space.
In theory. Practice tends to be complicated. The Russians performed a number of experiments in this area, from early Soyuz through Mir.  http://eagar.mit.edu/EagarPapers/Eagar136.pdf covers some of this.

Offline mlorrey

  • Member
  • Senior Member
  • *****
  • Posts: 2173
  • International Spaceflight Museum
  • Grantham, NH
  • Liked: 23
  • Likes Given: 5
Re: Space Industrial Operations: Welding in Space
« Reply #10 on: 04/25/2009 08:35 pm »
I found an interesting idea that has not been thought of for welding in space - Newtons second law.

A hot gas welding apparatus used in space will have a micro-nozzle, facing the exact opposite direcrtion of the arch vector, which will provide a constant counter thrust. Otherwise, the welder and the gun will simply fly away from the work area into space.
Its been thought of, and is why oxy-acetylene welding is not viable in space.
Uh, no. Figure out how much thrust it actually generates. Hint: If you weld on earth, you have to hold the torch up against gravity, and turning it on and lighting it doesn't significantly reduce this effort.

Astronauts on EVA are affected by all kinds of forces, that's why they use tethers, hand rails, foot restraints etc. A few ounces of thrust from a torch would be nothing compared to things they already do routinely... like bashing stuff with hammers.

None of this is to say that that combustion based welding would be a good choice.
Quote
You kinda left out ARC, Mig and Tig welding, all of which are fine in vacuum. In fact they should work better in space.
In theory. Practice tends to be complicated. The Russians performed a number of experiments in this area, from early Soyuz through Mir.  http://eagar.mit.edu/EagarPapers/Eagar136.pdf covers some of this.

that links not working
VP of International Spaceflight Museum - http://ismuseum.org
Founder, Lorrey Aerospace, B&T Holdings, ACE Exchange, and Hypersonic Systems. Currently I am a venture recruiter for Family Office Venture Capital.

Offline hop

  • Senior Member
  • *****
  • Posts: 3352
  • Liked: 553
  • Likes Given: 891
Re: Space Industrial Operations: Welding in Space
« Reply #11 on: 04/26/2009 12:42 am »
Quote from: mlorrey link=topic=4710.msg395455#msg395455
that links not working
Odd, it was working last night but the page seems to be down now. The paper is:

  "In-Space Welding, Visions and Realities," D. Tamir, T. A. Siewert, K. Masubuchi, L. Flanigan, R. Su, and T.W. Eagar, in Proc. of Thirtieth Space Congress: "Yesterday's Vision is Tomorrow's Reality", (4), 1.9 - 1.16, Cocoa Beach, Florida, 1993.
« Last Edit: 04/26/2009 12:42 am by hop »

Offline Axel

  • Member
  • Posts: 27
  • Liked: 0
  • Likes Given: 0
Re: Space Industrial Operations: Welding in Space
« Reply #12 on: 05/03/2009 10:38 pm »
Quote from: mlorrey link=topic=4710.msg395455#msg395455
that links not working
Odd, it was working last night but the page seems to be down now.

The link worked for me right now.

Offline mlorrey

  • Member
  • Senior Member
  • *****
  • Posts: 2173
  • International Spaceflight Museum
  • Grantham, NH
  • Liked: 23
  • Likes Given: 5
Re: Space Industrial Operations: Welding in Space
« Reply #13 on: 05/04/2009 02:32 am »
Quote from: mlorrey link=topic=4710.msg395455#msg395455
that links not working
Odd, it was working last night but the page seems to be down now.

The link worked for me right now.


Works for me now, thanks to whoever fixed it.

Actually, the paper you cite here mentions GTAW as one of the four, and seems to prefer it. GTAW (Gas Tungsten Arc Welding) is also referred to as TIG (Tungsten Inert Gas) welding, which was one of the methods I mentioned earlier. Thanks for the confirmation.
« Last Edit: 05/04/2009 02:39 am by mlorrey »
VP of International Spaceflight Museum - http://ismuseum.org
Founder, Lorrey Aerospace, B&T Holdings, ACE Exchange, and Hypersonic Systems. Currently I am a venture recruiter for Family Office Venture Capital.

Offline First Welder In Space

  • Member
  • Posts: 3
  • Liked: 0
  • Likes Given: 0
Re: Space Industrial Operations: Welding in Space
« Reply #14 on: 07/10/2012 02:31 am »
So much of what has been discussed on this website involves propulsion, energy production systems, life support, and radiation mitigation, however little has been said (atleast that I can find) about basic industrial processes which will be useful in the space environment. Periodically I would like to explore various industrial processes which may prove useful in space.

Among these is arc welding which has so far been explored a little by the Russians onboard one of the Salyut space stations back in early seventies, I think. Apparently they tried some GTAW (gaseous tungsten arc welding) and Electron beam welding experiments: the amassed enough information to publish a book which I have been unable to locate. Several small Shuttle Getaway Specials were performed to look at arc welding in the space environment, but results have been difficult to come by.

What issues could we expect to confront in welding in space or vacuum; zero g or low-g situations?

   Obviously because of the vacuum it would seem straight 'stick' welding might be the most favorable form of welding—however, how difficult is it to 'strike and arc' in hard vacuum? To ignite an arc, will some carrier gas like argon with a tad bit of neon be necessary to establish an arc, or can simply 'slapping' the electrode against the 'work' be enough to vaporize enough metal to establish an arc?

   Welder design: conventional earth bound industrial arc welders (such as a Lincoln or Miller portable welder) typically either use a 20 hp gasoline or diesel engine to drive a specially wound generator to provide the 10 KW of 20-30vac at 300-400 amps for the welding arc. Air is used to cool the windings in the generator. Obviously in space something different must be used: assuming of course we have enough 'station' power available, what would the design of the unit look like? Might it use a solid state inverter, transformer setup to convert high voltage DC to low voltage AC for welding? Or would it be better to use a dynamotor to convert DC into low voltage AC using a motor generator setup? To minimize or neutralize transient torques from startup, spin down and operational transients of a space arc welder, will it then be necessary to use two mechanically coupled but counter rotating motor/generator units, to minimize torque transients? What about cooling? Using a pressurized case with something like nitrogen blown through the electrical and mechanical parts, and then chilled by a vapor compression freon loop coupled to an external radiator could do the job, certainly, but how big of a radiator do you need? Could you do the same cooling job passively using an ammonia “heat pipe” and condensing radiator?

What about splatter of liquid metal from the work area? Do you need to design a spacesuit 'overall' and bib that protects it from molten splatter? Or do you weld in a vacuum version of a 'glove box?' What about a welding visor for space suits—do you need one externally, or will you just end up needing a specially designed space suit just for welding operations?

These are just some of the questions I'd like to explore:
Is welding practical in space? Are there alternatives? What kinds of special safety precautions would astronaut welders need to follow on orbital or lunar welding operations? Does the lack of gravity and air make a huge difference in the theory and operation of arc welding?What kinds of systems are needed to make welding practical in zero-g and vacuum? Will welding be practical in the low CO2 pressure of Mars' atmosphere? And here's another one: will the welds hold up well to atomic oxygen bombardment from low earth orbit positions, or will special coatings like gold need to be applied?

What do you think?

What I think is ,Is that NASA and our ESA and Russian counter parts need to research this matter vigorously. Welding is a very essential part of construction, from spacecraft all the way down to our basic steel structures. It also reduces weight of materials because it allows us to transport structural components in smaller sections. Since aluminum and titanium are also weldable, repairs of a lot of different types of spacecraft becomes possible. Had the whole in columbia been detected, and had this issue been addressed and actual experiments been done, it could have been patched, retiled, and these seven people would still be alive. Think about it. Yes, Welding technology can be adapted to address the problems of power output. My own feelings on the best processes for space are GTAW, and GMAW( MIG And Tig). the only forseeable problems are overcoming newtonian physics and atmosphere. However, if you can weld underwater, you should reasonably be able to do it in space. I could go on and on here, but this is something one of us needs to share with nasa now, either contact nasa or the astronauts please.

Offline First Welder In Space

  • Member
  • Posts: 3
  • Liked: 0
  • Likes Given: 0
Re: Space Industrial Operations: Welding in Space
« Reply #15 on: 07/10/2012 02:40 am »
I found an interesting idea that has not been thought of for welding in space - Newtons second law.

A hot gas welding apparatus used in space will have a micro-nozzle, facing the exact opposite direcrtion of the arch vector, which will provide a constant counter thrust. Otherwise, the welder and the gun will simply fly away from the work area into space.
Agreed, if using oxy/acet, which is fast becoming obsolete. A mig torch can be held in place thus canceling reverse thrust, the problem would be the necessity of a shielding gas which could act as a thruster and could not be used in a vacuum as far as i am aware. The environment around the the joint would have to have some sort of atmosphere or the wire or electrode would have to have some sort of flux within it. which they do. I find it hard to believe that welding in a vacuum has not been experimented with.  So I agree partially, physics and vacuum first must be addressed.

Offline Nomadd

  • Senior Member
  • *****
  • Posts: 8840
  • Lower 48
  • Liked: 60430
  • Likes Given: 1305
Re: Space Industrial Operations: Welding in Space
« Reply #16 on: 07/10/2012 07:06 am »
 Or, the welder could just attach himself to whatever he's working on.
Those who danced were thought to be quite insane by those who couldn't hear the music.

Offline JohnFornaro

  • Not an expert
  • Senior Member
  • *****
  • Posts: 10974
  • Delta-t is an important metric.
  • Planet Eaarth
    • Design / Program Associates
  • Liked: 1257
  • Likes Given: 724
Re: Space Industrial Operations: Welding in Space
« Reply #17 on: 07/10/2012 03:32 pm »
You kinda left out ARC, Mig and Tig welding, all of which are fine in vacuum. In fact they should work better in space. The only unique equipment you are going to need is a magnetic device to grab slag spall, otherwise you create a lot of space junk issues.

It's not the vacuum so much as it is the lack of gravity to control sputter.  And what about non magnetic materials? 
Sometimes I just flat out don't get it.

Offline First Welder In Space

  • Member
  • Posts: 3
  • Liked: 0
  • Likes Given: 0
Re: Space Industrial Operations: Welding in Space
« Reply #18 on: 07/10/2012 09:11 pm »
You kinda left out ARC, Mig and Tig welding, all of which are fine in vacuum. In fact they should work better in space. The only unique equipment you are going to need is a magnetic device to grab slag spall, otherwise you create a lot of space junk issues.

It's not the vacuum so much as it is the lack of gravity to control sputter.  And what about non magnetic materials? 


like i said, aluminum is definitely non ferrous, i agree about the spatter, welding does create a slight magnetic field. these issues are definitely something we all need to go back and forth with. However, i do intend to do a lot of research here in my spare time, since i am a certified welder, and i love the continued exploration of space. we need to keep going on this so let's work the problem ladies and gentleman. Have a great week :)

Offline A_M_Swallow

  • Elite Veteran
  • Senior Member
  • *****
  • Posts: 8906
  • South coast of England
  • Liked: 500
  • Likes Given: 223
Re: Space Industrial Operations: Welding in Space
« Reply #19 on: 07/10/2012 09:22 pm »
If the spatter is charged with static electricity then an electric field can be used to catch it.
« Last Edit: 07/10/2012 09:23 pm by A_M_Swallow »

Tags:
 

Advertisement NovaTech
Advertisement Northrop Grumman
Advertisement
Advertisement Margaritaville Beach Resort South Padre Island
Advertisement Brady Kenniston
Advertisement NextSpaceflight
Advertisement Nathan Barker Photography
0