Welding Mr. Huebsch

Behavioral Objectives Metal Basics Welding Equipment Welding Safety ARC Welding MIG Welding Welding Education

Metal Basics Metals come from natural deposits of ore in the earth’s crust. Two methods of mining open pit and underground ore are Selective – precise veins are worked (high grade) Bulk – Large quantities (low grade) Two types of ore are Ferrous – high iron content, 20x more abundant than non- ferrous, magnetic Non-Ferrous – low or no iron content, not magnetic

Metal Basics Types of Metal Ferrous (iron) Non-Ferrous (no iron) Cast Iron Mild Steel Stainless steel Wrought Iron Carbon Steel Forged Steel Titanium Non-Ferrous (no iron) Aluminum Brass Copper Gold Silver Lead Magnesium

Metal Basics Ice Steel Solid, Liquid, Gas Like ice metal can exist in these three stages Ice Solid below its 32° Fahrenheit melting point Heat to 32° and up it turns to water Heat to 212°, begins to boil and vaporize Steel Solid at or below 2,786° Heat to 2,786° and it turns to a liquid or molten Heat over 5,500° begins to vaporize

Metal Basics Heat Control Too cold won’t weld Too hot and vaporize the metal Different fuels offer different tempts Color of metal can indicate tempt. Refer to charts and keep in shop To control the weld puddle, you must learn how to judge and control the temp. of the metal you’re welding!

Welding Equipment Oxyacetylene Brazing & Soldering Arc Welding SMAW (Shield metal arc welding) MIG Welding (GMAW) Gas Metal Arc Welding TIG Welding (Tungsten Inert Gas) Tig Video Spot Welding EBW (Electron Beam Welding) thin electron beam used to fusion weld two or more parts together when other methods won’t work.

Arc Welding AC or DC Power source Electrode Cable Electrode Holder 2.2.3 Electrode Holder - The electrode holder connects to the welding cable and con- ducts the welding current to the electrode.  The insulated handle is used to guide the electrode over the weld joint and feed the electrode over the weld joint and feed the electrode into the weld puddle as it is consumed.  Electrode holders are available in different sizes and are rated on their current carrying capacity. 2.2.4 Ground Clamp - The ground clamp is used to connect the ground cable to the work piece.  It may be connected directly to the work or to the table or fixture upon which the work is positioned.  Being a part of the welding circuit, the ground clamp must be capable of carrying the welding current without overheating due to electrical resistance. 2.2.5 Welding Cables - The electrode cable and the ground cable are important parts of the welding circuit.  They must be very flexible and have a tough heat-resistant insulation. Connections at the electrode holder, the ground clamp, and at the power source lugs must be soldered or well crimped to assure low electrical resistance.  The cross-sectional area of the cable must be sufficient size to carry the welding current with a minimum of voltage drop. Increasing the cable length necessitates increasing the cable diameter to lessen resistance and voltage drop.   2.2.6 Coated Electrodes - Various types of coated electrodes are used in shielded metal arc welding.  Electrodes used for welding mild or carbon steels are quite different than those used for welding the low alloys and stainless steels.  Details on the specific types will be covered in subsequent lessons. Ground Cable Electrode Work

Arc Welding Coating Core rod Shielding gasses Solidified slag Molten Pool Work Piece

MIG Welder Metal intert gas – changed to Gas Metal Arc Welding http://www.weldguru.com/Mig.html Metal intert gas – changed to Gas Metal Arc Welding

MIG Welder

Welding Safety Risks Precautions Ventilation Explosion Fire Eye radiation burns (60 secs.) Skin Burns Chemical Precautions Ventilation Boots, leather apron, leather gloves Eye protection (ultraviolet light) Skin Burns

Welding Safety

Welding Education Learn in a formal classroom On the job training If you are Considering a career in welding check out this web site. Education-Portal.com gives a great overview of welding educational requirements. http://education- portal.com/welding_education.html