Arc Welding Introduction: Difference between revisions

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== Safety ==
== Safety ==
=== Dangers ===
[[PPE|Personal protection]]: [[File:Protection - welding mask.svg|50px]] [[File:Protection - gloves.svg|50px]] [[File:protection - protective clothing.svg|50px]]
* extreme heat
 
* CRITICAL HAZARD - extreme bright arc
Make sure you cover yourself completely, there should be no exposed skin at all!
** light damages eyes, including permanent blindness if used without appropriate protection
* cotton clothing - synthetics could melt
** UV radiation burns exposed skin
* [[Welding Jacket|welding jacket]]
* [[Welding Gloves|welding gloves]] over the jacket
* ideally also a fireproof apron against molten metal drops and as additional radiation protection
 
Protect your eyes with a [[Welding Helmet|welding helmet]] during welding, and [[goggles]] when hammering & brushing off slag
 
{| class="wikitable"
|-
! Dangers !! Precautions
|-
| [[File:danger - optical radiation.svg|50px]] CRITICAL HAZARD - extremely bright arc
* light damages eyes, risks include permanent blindness if used without appropriate protection
* UV radiation burns exposed skin
||
* wear proper [[PPE|personal protection]] (see above)
* immediately stop if '''anything''' seems to be wrong with the welding helmet
|-
| [[File:danger - heat.svg|50px]] extreme heat
* splattering molten metal
* splattering molten metal
* sharp & hot slag pieces
* sharp & hot slag pieces
* exposed electricity (up to 60 V DC, 100+ A)
|| make sure there are no gaps in your [[PPE|personal protection]], e.g. between pants and shoes or jacket and gloves
** still below ''zulässige Berührungsspannung'' - minor risk
|-
* toxic fumes (e.g. ozone, flux components, nitrous gases, heavy metal particles)
| toxic fumes (e.g. ozone, flux components, nitrous gases, heavy metal particles)
** galvanized steel ''(verzinkter Stahl)'' releases zinc oxide when welded which can give you "metal fume fever"<sup> [https://www.metalsupermarkets.com/welding-galvanized-steel/]</sup>
* galvanized steel ''(verzinkter Stahl)'' releases zinc oxide when welded which can give you "metal fume fever"<sup> [https://www.metalsupermarkets.com/welding-galvanized-steel/]</sup>
** stainless steel releases hexavalent chromium (carcinogenic)
* stainless steel releases hexavalent chromium (carcinogenic)
** other coatings may also release all sorts of unknown compounds when vaporized
* other coatings may also release all sorts of unknown compounds when vaporized
* in some cases the electrode may get stuck on the workpiece upon striking an ark
||
** if you can't remove it from the workpiece quickly, turn off the welder and then remove the electrode
** usually this can be caused if the setting on the welder is wrong or due to old electrodes
 
=== Precautions ===
* wear proper [[PPE|personal protection]]:
** cotton clothing - synthetics could melt!
*** cover yourself completely, there should be no exposed skin at all
** [[Welding Helmet|welding helmet]] during welding, [[goggles]] when hammering & brushing off slag
** [[Welding Jacket|welding jacket]]
** [[Welding Gloves|welding gloves]] over the jacket
** ideally also a fireproof apron against molten metal drops and as additional radiation protection
* immediately stop if '''anything''' seems to be wrong with the welding helmet
* [[grind]] away '''any''' surface coatings (e.g. galvanization, paint) before welding, they could generate harmful fumes or at least obstruct your weld
* [[grind]] away '''any''' surface coatings (e.g. galvanization, paint) before welding, they could generate harmful fumes or at least obstruct your weld
* take care of good ventilation - our [[Welding Enclosure|welding enclosure]] is open at the top but that alone might not be enough for long sessions or difficult materials! Also, you should obviously avoid breathing in the fumes.
* take care of good ventilation - our [[Welding Enclosure|welding enclosure]] is open at the top but that alone might not be enough for long sessions or difficult materials! Also, you should obviously avoid breathing in the fumes.
* reduce the chances of electric accidents:<sup> [https://www.bghm.de/fileadmin/user_upload/Arbeitsschuetzer/Gesetze_Vorschriften/Informationen/209_010.pdf]</sup>
|-
** make sure you are isolated (proper gloves, shoes and/or floor mat) from the workpiece, especially do not touch the electrode and the workpiece simultaneously
| [[File:danger - high voltage.svg|50px]] exposed electricity (up to 60 V DC, 100+ A)
** unplug the welding transformer when not in use
* still below ''zulässige Berührungsspannung'' - minor risk of shock
** do not use two welding transformers on the same workpiece
* equipment may overheat
** remove the welding electrode before putting the holder down (NEVER on your workpiece or anything connected to the power!)
|| reduce the chances of electric accidents:<sup> [https://www.bghm.de/fileadmin/user_upload/Arbeitsschuetzer/Gesetze_Vorschriften/Informationen/209_010.pdf]</sup>
** if you weld for longer, make sure that the cable drum is completely unfolded - a winded cable drum will induce current and heat up the cables, which may lead to a molten cable coat.
* make sure you are isolated (proper gloves, shoes and/or floor mat) from the workpiece, especially do not touch the electrode and the workpiece simultaneously
* unplug the welding transformer when not in use
* do not use two welding transformers on the same workpiece
* remove the welding electrode before putting the holder down (NEVER on your workpiece or anything connected to the power!)
* if you weld for longer, make sure that the cable drum is completely unfolded - a winded cable drum will induce current and heat up the cables, which may lead to a molten cable coat.
|-
* in some cases the electrode may get stuck on the workpiece upon striking an ark - if you can't remove it from the workpiece quickly, turn off the welder and then remove the electrode || use the correct setting on the welder or switch to a new electrode
|}


== Suggested Reading ==
== Suggested Reading ==

Revision as of 20:10, 1 September 2019

This is the content required for an introduction to our welding transformer - reading this does NOT replace the mandatory session with a tutor! It will make it a lot quicker though ;-)

Let's begin! First off, make sure you have read the machine's wiki page.

Safety

Personal protection: Protection - welding mask.svg Protection - gloves.svg Protection - protective clothing.svg

Make sure you cover yourself completely, there should be no exposed skin at all!

  • cotton clothing - synthetics could melt
  • welding jacket
  • welding gloves over the jacket
  • ideally also a fireproof apron against molten metal drops and as additional radiation protection

Protect your eyes with a welding helmet during welding, and goggles when hammering & brushing off slag

  • in some cases the electrode may get stuck on the workpiece upon striking an ark - if you can't remove it from the workpiece quickly, turn off the welder and then remove the electrode || use the correct setting on the welder or switch to a new electrode
Dangers Precautions
Danger - optical radiation.svg CRITICAL HAZARD - extremely bright arc
  • light damages eyes, risks include permanent blindness if used without appropriate protection
  • UV radiation burns exposed skin
  • wear proper personal protection (see above)
  • immediately stop if anything seems to be wrong with the welding helmet
Danger - heat.svg extreme heat
  • splattering molten metal
  • sharp & hot slag pieces
make sure there are no gaps in your personal protection, e.g. between pants and shoes or jacket and gloves
toxic fumes (e.g. ozone, flux components, nitrous gases, heavy metal particles)
  • galvanized steel (verzinkter Stahl) releases zinc oxide when welded which can give you "metal fume fever" [1]
  • stainless steel releases hexavalent chromium (carcinogenic)
  • other coatings may also release all sorts of unknown compounds when vaporized
  • grind away any surface coatings (e.g. galvanization, paint) before welding, they could generate harmful fumes or at least obstruct your weld
  • take care of good ventilation - our welding enclosure is open at the top but that alone might not be enough for long sessions or difficult materials! Also, you should obviously avoid breathing in the fumes.
Danger - high voltage.svg exposed electricity (up to 60 V DC, 100+ A)
  • still below zulässige Berührungsspannung - minor risk of shock
  • equipment may overheat
reduce the chances of electric accidents: [2]
  • make sure you are isolated (proper gloves, shoes and/or floor mat) from the workpiece, especially do not touch the electrode and the workpiece simultaneously
  • unplug the welding transformer when not in use
  • do not use two welding transformers on the same workpiece
  • remove the welding electrode before putting the holder down (NEVER on your workpiece or anything connected to the power!)
  • if you weld for longer, make sure that the cable drum is completely unfolded - a winded cable drum will induce current and heat up the cables, which may lead to a molten cable coat.

Suggested Reading

Besides these safety notes, you should read our page about welding electrodes.

These websites may also be interesting:

Demonstration

The tutor will show you these steps in detail:

  • set up your work in the welding enclosure
    • red curtain far away
    • close gaps, e.g. with spring clamps (long-term solution needed!)
    • bring a light with you, if necessary
  • try striking an arc and depositing metal on a scrap piece (e.g. in the shape of your initials)
    • it's good to experience the often scary sensation of your first arc ignition with your tutor ;-)
    • once there is a steady arc, push forward and make little circles in the weld pool to "mix" the workpiece(s) with the deposited material

Waiting List

This introduction takes longer than many others and usually can't be done spontaneously during regular opening times. If you would like to receive it, please add yourself to >> this list << and we will find a good time once a few members are on it!