Presentation on theme: "Remember there is no such thing as a perfect weld."— Presentation transcript:
1 Remember there is no such thing as a perfect weld. Learning how to Weld.Sit down and be quiet.Remember there is no such thing as a perfect weld.
2 Welding definedArc welding is one of several fusion processes for joining metals. By applying intense heat, metal at the joint between two parts is melted and caused to intermix – directly, or more commonly, with an intermediate molten filler metal. Upon cooling and solidification, a metallurgical bond is created.The arc produces a temperature of about 6500 degrees F at the tip of the rod.
3 Safety Must wear welding helmet Must wear long sleeve shirt Must wear blue jeans or pantsMust wear close toed shoesMust wear welding gloves (both hands)Safety glasses worn (under helmet)
4 Different types of welding OFW Oxyfuel Gas WeldingSMAW Shielded Metal Arc WeldingSAW Submerged Arc WeldingGMAW Gas Metal Arc Welding (MIG)FCAW Flux Cored (Wire) Arc WeldingGTAW Gas Tungsten Arc Welding (TIG)PAW Plasma Arc Welding
5 Basic Knowledge Type of weld joints: T, Butt, Lap, Corner, and Edge Type of welds: Fillet weld or groove weldFillet weld – A right triangle cross section of filler metal deposit joining two pieces of base material at or nearly perpendicular to each other.Groove weld – requires some base material prep work of at least a single bevel face.
6 Basic KnowledgeWelding Positions: The main key of knowing welding positions is ask what is the weld face in? Below is a list of numeric then alpha meanings:1 stands for flat position2 stands for horizontal position3 stands for vertical position4 stands for overhead positionF stands for fillet weldG stands for groove weldSo if you are welding a vertical fillet weld, what numeric alpha position are we welding?
7 Basic Knowledge Answer is 3F This knowledge is found on blueprints in or near the welding symbols.More symbol reading will be covered in your next year classes.
8 Welding Positions Flat welds are either 1F or 1G Horizontal welds are either 2F or 2GVertical welds are either 3F or 3GOverhead welds are either 4F or 4G
9 Welding Rods What does those numbers mean? The “E” stands for arc welding electrodeFirst two represent the tensile strengthE60 is 60,000 lbs strengthE110 is 110,000 lbs strength
10 Welding RodsNext to last digit indicates position the electrode can be used in.3 different positions exist:1 – is for use in all positions2 – is for flat and horizontal only3 – is for flat welding onlyLast digit represents AC, DC+ (reverse polarity) or DC- (straight polarity)
11 Welding Rods Here is a list of the numbers: 4 AC, DC-, or DC+ 5 DC+ 0 DC+ electrode (reverse polarity)1 AC or DC- (straight polarity)2 AC or DC-3 AC, DC-, or DC+4 AC, DC-, or DC+5 DC+6 AC or DC+8 AC, DC-, or DC+
12 Welding RodsE6010 rod is used for all position in DC reverse and produces a deep penetrating weld, does not leave a superior weld appearance.E6011 rod is very similar to 6010, but can be used with AC or DC (both).E6013 rod can be used in AC & DC and produces a medium penetrating weld with superior weld appearance.E7018 rod is known as low hydrogen electrode in AC or DC (both). This electrode must be kept really dry, if allowed to get wet, you must dry it before using.
13 What is polarity?DC Straight – electrode is negative and the weld will have a faster melt off and deposit rate. The weld will have medium penetration.DC Reverse – electrode is positive and the weld penetration will be deep.
14 Welding Angle based on Positions The next slide will show you the different angle to hold the electrodes based on the welding position you are welding in.