Learning how to Weld.

Sit down and be quiet.

Remember there is no such thing as a perfect weld.

Welding defined

Arc 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.

Safety

Must wear welding helmet Must wear long sleeve shirt Must wear blue jeans or pants Must wear close toed shoes Must wear welding gloves (both hands) Safety glasses worn (under helmet)

Different types of welding

OFW Oxyfuel Gas Welding SMAW Shielded Metal Arc Welding SAW Submerged Arc Welding GMAW Gas Metal Arc Welding (MIG) FCAW Flux Cored (Wire) Arc Welding GTAW Gas Tungsten Arc Welding (TIG) PAW Plasma Arc Welding

Basic Knowledge

Type of weld joints: T, Butt, Lap, Corner, and Edge Type of welds: Fillet weld or groove weld Fillet 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.

Basic Knowledge

Welding 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 position– 2 stands for horizontal position– 3 stands for vertical position– 4 stands for overhead position

– F stands for fillet weld– G stands for groove weld

So if you are welding a vertical fillet weld, what numeric alpha position are we welding?

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.

WeldingPositions

Flat welds are either 1F or 1G

Horizontal welds are either 2F or 2G

Vertical welds are either 3F or 3G

Overhead welds are either 4F or 4G

Welding Rods

What does those numbers mean? The “E” stands for arc welding electrode First two represent the tensile strength

– E60 is 60,000 lbs strength– E110 is 110,000 lbs strength

Welding Rods

Next to last digit indicates position the electrode can be used in.

3 different positions exist:– 1 – is for use in all positions– 2 – is for flat and horizontal only– 3 – is for flat welding only

Last digit represents AC, DC+ (reverse polarity) or DC- (straight polarity)

Welding Rods

Here is a list of the numbers:– 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+

Welding Rods

E6010 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.

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.

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.

How to setup

Attach your ground clamp to the table or the work piece.

Put the rod in the stinger Get gloves on, welding helmet down Move your rod down to the metal to strike

How to strike the Arc

First, you will drag to start

Do not stab Gently touch and drag Next, you will move

back to start a puddle Puddle up before

starting to move on

Actually Welding

Now that you have your puddle going…

Watch rod/metal relationship

Watch speed of movement

Most important watch your puddle

Welding Pictures

Running your puddle

Here is a great shot of a running puddle

Notice how you can see the path of welding

Review

Wear proper safety equipment

Lightly drag, do not stab

Watch puddle, rod/metal relationship