Arc Welding Basics

2 Unit Topics Topics included in this overview are: –Introduction  What is Arc Welding?  Why is Welding Important?  Why Learn to Weld? –Careers in Welding –The American Welding Society (AWS) –Welding Safety –Basic Electricity –Welding Fundamentals –Welding Certification

3 Objectives Upon successful completion of this unit of study, you will be able to … –Identify definitions and terminology associated with welding –Demonstrate safe working habits in the welding environment –Name the parts and types of welds and weld joints –Interpret basic welding symbol information –Identify opportunities available to welders

Introduction

5 What is Arc Welding? Arc welding is most commonly used to join two pieces of metal –The welder creates an electric arc that melts the base metals and filler metal (consumable) together so that they all fuse into one solid piece of metal Steel Pipe – Tack Welded Root Pass or “Stringer Bead” Final weld after several beads are made

6 Why is Welding Important? Many things around us are welded … –Pipelines that bring fresh water –Towers that carry electricity to houses –Cars and buses that take people where they need to go

7 Why Learn to Weld? Welding is so HOT …. it’s COOL! –Welding can help build a successful career so you can get the things you want in life –Skilled welders are in demand – people use things that are welded everyday! –Welding can be fun and safe –It is challenging and high-tech

8 Basic Steps of Arc Welding Prepare the base materials: remove paint and rust Choose the right welding process Choose the right filler material Assess and comply with safety requirements Use proper welding techniques and be sure to protect the molten puddle from contaminants in the air Inspect the weld

9 The American Welding Society Who is the AWS? –American Welding Society –It is a non-profit organization whose membership includes:  Individuals  Students  Companies What do they do? –Their purpose is to:  Advance the science, technology, and application of welding and allied processes including: joining, brazing, soldering, cutting, and thermal spray  Standardize classification of electrode and base material codes  Standardize process procedures  Provide welding certification

10 Careers in Welding

11 Careers in Welding Engineering Racing Industrial Sales Farm Repair and Fabrication Production Welding Military Teaching Maintenance Robotics Ironworker/ Skilled Trades Auto Technician Artist Metal Sculpting Owning Your Own Business Job opportunities in welding are changing … Welding can be valuable as a job skill or as a full-time job For more information on welding careers, please see the e- learning introduction

12 How Much Money Can You Make? Recent statistics show that some welding jobs pay $25.00 per hour -If you worked five days a week for one year, how much money would you make? 83% of people with welding jobs were offered medical benefits - Higher than any other work sector except government For more information on welding statistics, please log on to

13 Application Activity

14 Application Activity Let’s explore some career possibilities in welding Please log on to a computer Working with a team member, research the websites to the right and explore information about welding careers In 60 minutes, be prepared to answer the following questions: –What careers in welding interest you the most? –How can welding be high tech? –How much money can be made annually in this chosen career field? –Where can you get a job in welding and what are the basic requirements? –What are some job advancement opportunities available in the welding industry? America's Job Bank ( Classifieds Employment ( Yahoo! Careers ( MONSTER.COM ( ( CareerBuilder (

15 Welding Safety

16 Welding can be safe when sufficient measures are taken to protect yourself and others from potential hazards Students should read and understand the following before welding: –Warning Labels –Material Safety Data Sheets (MSDS) Students should also be familiar with the following information –‘Safety in Welding, Cutting, and Allied Processes’ (ANSI Z49.1) –Lincoln Electric’s ‘Arc Welding Safety’ (E205) Arc Welding Safety

17 Warning Labels Understand and follow all warning labels found: –On welding equipment –With all consumable packaging –Within instruction manuals

18 Material Safety Data Sheets Material Safety Data Sheets (MSDS) are: –Required by law and OSHA –Created by the manufacturer of a product per OSHA guidelines –Designed to inform users –Shipped with every box of Lincoln Electric consumable product –Available free online at: s/msds/ front

19 MSDS - Continued MSDS outlines a product’s:  Identity and composition  Potential hazards  Safe use  Handling information  Manufacturer contact information back

20 ANSI Z49.1 ANSI Z49.1: Safety in Welding, Cutting, and Allied Processes –A safety document published by the American Welding Society that covers safe practices in the welding environment –To get your free copy, go to:  E205: Arc Welding Safety –A safety document summarizing many of the hazards and safe practices for welding –Download and print your own copy at:  –Free copies available from Lincoln Electric at:  Access the E-learning

21 Arc Welding Safety Protect yourself and others from potential hazards including: –Fumes and Gases –Electric Shock –Arc Rays –Fire and Explosion Hazards –Noise –Hot objects

22 Fumes and Gases Fumes and gases can be hazardous to your health Keep your head out of the fumes Use enough ventilation, exhaust at the arc, or both, to keep fumes and gases from your breathing zone and the general area See product labeling and MSDS for ventilation and respirator requirements

23 Electric Shock Electric shock can kill Do not touch live electrical parts –Primary Voltage –230, 460 volt input power –Secondary Voltage – 6 to 100 volts for welding Insulate yourself from work and ground Follow all warnings on welding equipment Do not make repairs yourself, alert your instructor immediately!

24 Arc Rays Arc rays can injure eyes and burn skin The welding arc is brighter than the sun Precaution must be taken to protect your eyes and skin from UV radiation Wear correct eye and body protection

25 Fire and Explosion Hazards Welding sparks can cause fires and explosions Sparks and spatter from the welding arc can spray up to 35 feet from your work Flammable materials should be removed from the welding area or shielded from sparks and spatter Have a fire extinguisher ready Inspect area for fires 30 minutes after welding

26 Noise Loud noises can damage your hearing Keep loud noises at a safe level by using proper hearing protection such as: –Ear plugs –Ear muffs

27 Protective Clothing Welders must wear protective clothing for –Protection from sparks, spatter and UV radiation –Insulation from electric shock Protective clothing includes … –Fire-proof clothing without rolled sleeves, cuffs or frays –Work boots –Welding gloves, jackets, bibs, and fire- proof pants –Welding cap, helmet and safety glasses –Ear protection – ear plugs and muffs

28 Application Activity

29 Application Activity TIME TO PRACTICE –Go out to the lab –Demonstrate the use of proper safety precautions such as:  Reading warnings  Using proper protective clothing  Equipment inspection  Keeping your head out of the fume  Proper ventilation

30 Basic Electricity and Welding

31 The Arc Welding Circuit The electricity flows from the power source, through the electrode and across the arc, through the base material to the work lead and back to the power source

32 Basic Electricity Voltage – The electrical potential or pressure that causes current to flow –Measured in Volts Current – The movement of charged particles in a specific direction –Measured in Amps Polarity –DC- (Direct Current Electrode Negative) –DC+ (Direct Current Electrode Positive) –AC (Alternating Current) DC+ DC - AC

33 Math Terms and Welding

34 Math Terms in Welding Believe it or not, a lot of math is used in welding IPM Travel Speed = Inches per Minute Travel Speed The speed the electrode moves along the base material IPM Wire Feed Speed= Inches per Minute Wire Feed Speed The speed at which the wire is fed during wire welding Lbs/hr = Pounds per HourElectrode deposition rate CFH= Cubic Feet per Hour Shielding gas flow rate (wire welding) PSI= Pounds per Square Inch Tensile strength of a material and the pressure in gas cylinders L = LegFillet size measurement % = percentShielding gas mixture composition

35 Metals

36 Can All Metals Be Welded? Most metals can be welded, but not all The three most common weldable metals include: –Mild Steel - inexpensive and strong –Stainless Steel – does not rust –Aluminum – does not rust and is light weight Mild steel Stainless Steel Aluminum

37 Gauge Material thickness is sometimes measured by gauge from 36 (.004 in) to 3 (.2391 in) –For example, steel gauge and measurement in inches: PLEASE NOTE: As the gauge number gets smaller … the material thickness gets larger. 16 gauge =.051” 14 gauge =.064” 12 gauge =.081” 10 gauge =.102”

38 Types of Joints

39 Types of Joints There are 5 types of joints …

40 Parts of a Weld

41 Parts of a Weld Joint and Weld Heat Affected Zone

42 Fillet and Groove Welds Groove and fillet welds can be made on many types of joints

43 Fillet Weld Inspection Fillet welds should: –Have a flat to slightly convex face –Be uniform in appearance –Have equal leg size –Have good wash-in into base materials This is an example of a good fillet weld:

44 Welding Symbols

45 What are Welding Symbols? Welding symbols give the welder specific instructions about the weld including: –Placement –Size –Length –Process –Any other special notes Welding symbols are –Universally used –Governed by the AWS –Found on engineering drawings “How to Read Shop Drawings” available at

46 Welding Symbols Welding symbols contain information about the weld to be made –S – leg dimension of the weld –Triangle – the weld is to be made on the arrow side of this joint –Tail – any additional information required (i.e. position the weld is to be made) –Arrow - the joint the welding symbol applies to

47 Welding Positions

48 What are Welding Positions? There are various positions that a weld can be made in:

49 Welder Responsibilities

50 What are the Responsibilities of a Welder? Welders have many areas of important responsibilities These relate to: –Arc Welding Safety –Knowledge – Content –Attitude – Reactions –Skills – Performance –Work Habits – Daily Functions Always keep safety in mind when welding

51 Arc Welding Safety A welder MUST always follow safe work practices: –Students should read and understand the following before welding:  Warning Labels  Material Safety Data Sheets (MSDS) –Students should also be familiar with the following information  ‘Safety in Welding, Cutting, and Allied Processes’ (ANSI Z49.1)  Lincoln Electric’s ‘Arc Welding Safety’ (E205)

52 Knowledge - Content Welding can teach you about…. –Science when applying metallurgy, chemistry, electricity, etc. –Math when calculating angles, joint design, and weld size –English when communicating and interpreting drawings, codes, and procedures –Technical areas when performing the actual welding applications How much science and math went into the development of this bike?

53 Attitude The best welders demonstrate a can-do attitude when performing welding processes This means being able to… –Work as a team member –Communicate ideas to others –Listen to opinions of others –Promote a positive attitude –Provide solutions to problems –Take pride in workmanship These welders work together to inspect a weld.

54 Skills/Performance A welder must demonstrate technical skills when performing welding processes A welder must know how to: –Use hand tools and materials, to operate equipment in a safe, accurate, and consistent manner –Acquire and evaluate information needed for problem solving –Complete quality work –Maintain equipment There is no room for poor workmanship in NASCAR

55 Work Habits/Daily Functions A welder must practice good working habits when performing welding processes This means being able to … –Follow detailed verbal and written instructions –Maintain workspace, equipment, and tool cleanliness –Correctly fill out, maintain and submit time cards, work assignment cards, and other records as required –Follow safe working practices Agriculture teachers brush up on their welding skills at Lincoln Electric’s Welding Educator’s Workshop

56 Welding Certification

57 Welding Certification What is a welding certification? –Welding certifications are used to test a welder’s knowledge and welding skill –Certifications are available for many different processes, materials, and positions. Who certifies welders? –Certification programs are offered by many different types of organizations:  Companies  Skilled Trades  Military  Ship Builders  Pipelines  The American Welding Society

58 Welding Certification How can you become certified? –Certification testing is available at testing facilities all over the United States –The AWS offers many certifications including: welders, welding inspectors, and welding educators What is the value of a welding certification? –A welding certification proves that you have passed a test and are qualified for the job –As an AWS certified welder your name is kept in a national database which is used to notify you of jobs open in your area –It is a source of accomplishment and pride

59 English, Math, and Science Connection

60 English, Math, and Science Connection Many of the same concepts you learn in other classes are practiced in welding. In what other classes might you study the following terms?  75/25 – gas mixture  Volts  Amps  Degree/hr – cooling rate  In/min  Angles/degrees  Metallurgy  Fillet size  Current  Tension  Compression  Tensile strength  Yield  Blueprints  Depth/width ratio  Preheat temperature  Cubic feet per hour

61 National Academic Standards Crosswalk The unit just completed has covered parts of academic content listed in the National Academic Standards as follows: –NM-PROB.CONN.PK-12.3: Recognizes and applies mathematics in contexts outside of mathematics. –NLA-STANDARD 1: Uses the general skills and strategies of the writing process. –NLA-STANDARD 7: Uses reading skills and strategies to understand and interpret a variety of informational texts. –NS-PHYSICAL SCIENCE: (Experiences) interactions of energy and matter.