Guidelines For Shielded Metal Arc Welding (SMAW) For Shielded Metal Arc Welding ... SECTION 3 SHIELDED METAL ARC WELDING ... Arc Welding Hazards The symbols

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ProcessesStick (SMAW) Welding155 095 AJuly 2005Visit our website atwww.MillerWelds.comGuidelines ForShielded Metal ArcWelding (SMAW)WARNINGThis document contains general information about the topics discussed herein.This document is not an application manual and does not contain a completestatement of all factors pertaining to those topics.This installation, operation, and maintenance of arc welding equipment and theemployment of procedures described in this document should be conductedonly by qualified persons in accordance with applicable codes, safe practices,and manufacturers instructions.Always be certain that work areas are clean and safe and that proper ventilationis used. Misuse of equipment, and failure to observe applicable codes and safepractices, can result in serious personal injury and property damage.ARC WELDING can be hazardous.TABLE OF CONTENTSSECTION 1 SAFETY PRECAUTIONS - READ BEFORE USING 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1. Symbol Usage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2. Arc Welding Hazards 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3. Additional Symbols For Installation, Operation, And Maintenance 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4. California Proposition 65 Warnings 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5. Principal Safety Standards 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6. EMF Information 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SECTION 2 PRINCIPLES OF SHIELDED METAL ARC WELDING (SMAW) 5 . . . . . . . . . . . . . . . . . . . . . . . . . SECTION 3 SHIELDED METAL ARC WELDING (SMAW) PROCEDURE 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1. Typical Stick Welding Set-Up 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2. Electrode And Amperage Selection Chart 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-3. Striking An Arc Scratch Start Technique 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-4. Striking An Arc Tapping Technique 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5. Positioning Electrode Holder 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-6. Electrode Movement During Welding 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7. Conditions That Affect Weld Bead Shape 11 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8. Poor Weld Bead Characteristics 12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9. Good Weld Bead Characteristics 12 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10. Typical Weld Joints 13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11. Welding Butt Joints 14 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12. Welding Tee Joints 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13. Welding Lap Joints 15 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-14. Welding Horizontal Beads And Butt Joints 16 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15. Welding Vertical Beads And Butt Joints 17 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16. Welding Vertical Tee Joints And Lap Joints 18 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17. Welding Overhead Butt Joints And Tee Joints 19 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18. Weld Test 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . SECTION 4 WELDING TROUBLESHOOTING 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1. Porosity 20 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2. Excessive Spatter 21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-3. Incomplete Fusion 21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4. Lack Of Penetration 21 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-5. Excessive Penetration 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-6. Burn-Through 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7. Waviness Of Bead 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-8. Distortion 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155 095 Page 1SECTION 1 SAFETY PRECAUTIONS - READ BEFORE USINGsom _3/05 Warning: Protect yourself and others from injury read and follow these precautions.1-1. Symbol UsageMeans Warning! Watch Out! There are possible hazardswith this procedure! The possible hazards are shown inthe adjoining symbols. Marks a special safety message. Means Note; not safety related.This group of symbols means Warning! Watch Out! possibleELECTRIC SHOCK, MOVING PARTS, and HOT PARTS hazards.Consult symbols and related instructions below for necessary actionsto avoid the hazards.1-2. Arc Welding Hazards The symbols shown below are used throughout this manual tocall attention to and identify possible hazards. When you seethe symbol, watch out, and follow the related instructions toavoid the hazard. The safety information given below is onlya summary of the more complete safety information found inthe Safety Standards listed in Section 1-5. Read and follow allSafety Standards. Only qualified persons should install, operate, maintain, andrepair this unit. During operation, keep everybody, especially children, away.ELECTRIC SHOCK can kill.Touching live electrical parts can cause fatal shocksor severe burns. The electrode and work circuit iselectrically live whenever the output is on. The inputpower circuit and machine internal circuits are alsolive when power is on. In semiautomatic or automatic wire welding, thewire, wire reel, drive roll housing, and all metal parts touching thewelding wire are electrically live. Incorrectly installed or improperlygrounded equipment is a hazard. Do not touch live electrical parts. Wear dry, hole-free insulating gloves and body protection. Insulate yourself from work and ground using dry insulating matsor covers big enough to prevent any physical contact with the workor ground. Do not use AC output in damp areas, if movement is confined, or ifthere is a danger of falling. Use AC output ONLY if required for the welding process. If AC output is required, use remote output control if present onunit. Additional safety precautions are required when any of the follow-ing electrically hazardous conditions are present: in damplocations or while wearing wet clothing; on metal structures suchas floors, gratings, or scaffolds; when in cramped positions suchas sitting, kneeling, or lying; or when there is a high risk of unavoid-able or accidental contact with the workpiece or ground. For theseconditions, use the following equipment in order presented: 1) asemiautomatic DC constant voltage (wire) welder, 2) a DC manual(stick) welder, or 3) an AC welder with reduced open-circuit volt-age. In most situations, use of a DC, constant voltage wire welderis recommended. And, do not work alone! Disconnect input power or stop engine before installing orservicing this equipment. Lockout/tagout input power according toOSHA 29 CFR 1910.147 (see Safety Standards). Properly install and ground this equipment according to itsOwners Manual and national, state, and local codes. Always verify the supply ground check and be sure that inputpower cord ground wire is properly connected to ground terminal indisconnect box or that cord plug is connected to a properlygrounded receptacle outlet. When making input connections, attach proper grounding conduc-tor first double-check connections. Frequently inspect input power cord for damage or bare wiring replace cord immediately if damaged bare wiring can kill. Turn off all equipment when not in use. Do not use worn, damaged, undersized, or poorly spliced cables. Do not drape cables over your body. If earth grounding of the workpiece is required, ground it directlywith a separate cable. Do not touch electrode if you are in contact with the work, ground,or another electrode from a different machine. Do not touch electrode holders connected to two welding ma-chines at the same time since double open-circuit voltage will bepresent. Use only well-maintained equipment. Repair or replace damagedparts at once. Maintain unit according to manual. Wear a safety harness if working above floor level. Keep all panels and covers securely in place. Clamp work cable with good metal-to-metal contact to workpieceor worktable as near the weld as practical. Insulate work clamp when not connected to workpiece to preventcontact with any metal object. Do not connect more than one electrode or work cable to anysingle weld output terminal.SIGNIFICANT DC VOLTAGE exists in inverter-typewelding power sources after removal of inputpower. Turn Off inverter, disconnect input power, and discharge inputcapacitors according to instructions in Maintenance Sectionbefore touching any parts.Welding produces fumes and gases. Breathingthese fumes and gases can be hazardous to yourhealth.FUMES AND GASES can be hazardous. Keep your head out of the fumes. Do not breathe the fumes. If inside, ventilate the area and/or use local forced ventilation at thearc to remove welding fumes and gases. If ventilation is poor, wear an approved air-supplied respirator. Read and understand the Material Safety Data Sheets (MSDSs)and the manufacturers instructions for metals, consumables,coatings, cleaners, and degreasers. Work in a confined space only if it is well ventilated, or whilewearing an air-supplied respirator. Always have a trained watch-person nearby. Welding fumes and gases can displace air andlower the oxygen level causing injury or death. Be sure the breath-ing air is safe. Do not weld in locations near degreasing, cleaning, or spraying op-erations. The heat and rays of the arc can react with vapors to formhighly toxic and irritating gases. Do not weld on coated metals, such as galvanized, lead, orcadmium plated steel, unless the coating is removed from the weldarea, the area is well ventilated, and while wearing an air-suppliedrespirator. The coatings and any metals containing these elementscan give off toxic fumes if welded.155 095 Page 2Arc rays from the welding process produce intensevisible and invisible (ultraviolet and infrared) raysthat can burn eyes and skin. Sparks fly off from theweld.ARC RAYS can burn eyes and skin. Wear an approved welding helmet fitted with a proper shade of fil-ter lenses to protect your face and eyes when welding or watching(see ANSI Z49.1 and Z87.1 listed in Safety Standards). Wear approved safety glasses with side shields under yourhelmet. Use protective screens or barriers to protect others from flash,glare and sparks; warn others not to watch the arc. Wear protective clothing made from durable, flame-resistant mate-rial (leather, heavy cotton, or wool) and foot protection.Welding on closed containers, such as tanks,drums, or pipes, can cause them to blow up. Sparkscan fly off from the welding arc. The flying sparks, hotworkpiece, and hot equipment can cause fires andburns. Accidental contact of electrode to metal objects can causesparks, explosion, overheating, or fire. Check and be sure the area issafe before doing any welding.WELDING can cause fire or explosion. Remove all flammables within 35 ft (10.7 m) of the welding arc. Ifthis is not possible, tightly cover them with approved covers. Do not weld where flying sparks can strike flammable material. Protect yourself and others from flying sparks and hot metal. Be alert that welding sparks and hot materials from welding caneasily go through small cracks and openings to adjacent areas. Watch for fire, and keep a fire extinguisher nearby. Be aware that welding on a ceiling, floor, bulkhead, or partition cancause fire on the hidden side. Do not weld on closed containers such as tanks, drums, or pipes,unless they are properly prepared according to AWS F4.1 (seeSafety Standards). Connect work cable to the work as close to the welding area aspractical to prevent welding current from traveling long, possiblyunknown paths and causing electric shock, sparks, and firehazards. Do not use welder to thaw frozen pipes. Remove stick electrode from holder or cut off welding wire atcontact tip when not in use. Wear oil-free protective garments such as leather gloves, heavyshirt, cuffless trousers, high shoes, and a cap. Remove any combustibles, such as a butane lighter or matches,from your person before doing any welding. Follow requirements in OSHA 1910.252 (a) (2) (iv) and NFPA 51Bfor hot work and have a fire watcher and extinguisher nearby.FLYING METAL can injure eyes. Welding, chipping, wire brushing, and grindingcause sparks and flying metal. As welds cool,they can throw off slag. Wear approved safety glasses with sideshields even under your welding helmet.BUILDUP OF GAS can injure or kill. Shut off shielding gas supply when not in use. Always ventilate confined spaces or useapproved air-supplied respirator.HOT PARTS can cause severe burns. Do not touch hot parts bare handed. Allow cooling period before working on gun ortorch. To handle hot parts, use proper tools and/orwear heavy, insulated welding gloves andclothing to prevent burns.MAGNETIC FIELDS can affect pacemakers. Pacemaker wearers keep away. Wearers should consult their doctor beforegoing near arc welding, gouging, or spotwelding operations.NOISE can damage hearing.Noise from some processes or equipment candamage hearing. Wear approved ear protection if noise level ishigh.Shielding gas cylinders contain gas under highpressure. If damaged, a cylinder can explode. Sincegas cylinders are normally part of the weldingprocess, be sure to treat them carefully.CYLINDERS can explode if damaged. Protect compressed gas cylinders from excessive heat, mechani-cal shocks, physical damage, slag, open flames, sparks, and arcs. Install cylinders in an upright position by securing to a stationarysupport or cylinder rack to prevent falling or tipping. Keep cylinders away from any welding or other electrical circuits. Never drape a welding torch over a gas cylinder. Never allow a welding electrode to touch any cylinder. Never weld on a pressurized cylinder explosion will result. Use only correct shielding gas cylinders, regulators, hoses, and fit-tings designed for the specific application; maintain them andassociated parts in good condition. Turn face away from valve outlet when opening cylinder valve. Keep protective cap in place over valve except when cylinder is inuse or connected for use. Use the right equipment, correct procedures, and sufficient num-ber of persons to lift and move cylinders. Read and follow instructions on compressed gas cylinders,associated equipment, and Compressed Gas Association (CGA)publication P-1 listed in Safety Standards.155 095 Page 31-3. Additional Symbols For Installation, Operation, And MaintenanceFIRE OR EXPLOSION hazard. Do not install or place unit on, over, or nearcombustible surfaces. Do not install unit near flammables. Do not overload building wiring be sure power supply system isproperly sized, rated, and protected to handle this unit.FALLING UNIT can cause injury. Use lifting eye to lift unit only, NOT runninggear, gas cylinders, or any other accessories. Use equipment of adequate capacity to lift andsupport unit. If using lift forks to move unit, be sure forks arelong enough to extend beyond opposite side ofunit.OVERUSE can cause OVERHEATING Allow cooling period; follow rated duty cycle. Reduce current or reduce duty cycle beforestarting to weld again. Do not block or filter airflow to unit.STATIC (ESD) can damage PC boards. Put on grounded wrist strap BEFORE handlingboards or parts. Use proper static-proof bags and boxes tostore, move, or ship PC boards.MOVING PARTS can cause injury. Keep away from moving parts. Keep away from pinch points such as driverolls.WELDING WIRE can cause injury. Do not press gun trigger until instructed to doso. Do not point gun toward any part of the body,other people, or any metal when threadingwelding wire.MOVING PARTS can cause injury. Keep away from moving parts such as fans. Keep all doors, panels, covers, and guardsclosed and securely in place. Have only qualified persons remove doors,panels, covers, or guards for maintenance asnecessary. Reinstall doors, panels, covers, or guardswhen maintenance is finished and before re-connecting input power.READ INSTRUCTIONS. Read Owners Manual before using or servic-ing unit. Use only genuine Miller/Hobart replacementparts.H.F. RADIATION can cause interference. High-frequency (H.F.) can interfere with radionavigation, safety services, computers, andcommunications equipment. Have only qualified persons familiar withelectronic equipment perform this installation. The user is responsible for having a qualified electrician prompt-ly correct any interference problem resulting from the installa-tion. If notified by the FCC about interference, stop using theequipment at once. Have the installation regularly checked and maintained. Keep high-frequency source doors and panels tightly shut, keepspark gaps at correct setting, and use grounding and shielding tominimize the possibility of interference.ARC WELDING can cause interference. Electromagnetic energy can interfere withsensitive electronic equipment such ascomputers and computer-driven equipmentsuch as robots. Be sure all equipment in the welding area iselectromagnetically compatible. To reduce possible interference, keep weld cables as short aspossible, close together, and down low, such as on the floor. Locate welding operation 100 meters from any sensitive elec-tronic equipment. Be sure this welding machine is installed and groundedaccording to this manual. If interference still occurs, the user must take extra measuressuch as moving the welding machine, using shielded cables,using line filters, or shielding the work area.1-4. California Proposition 65 Warnings Welding or cutting equipment produces fumes or gases whichcontain chemicals known to the State of California to causebirth defects and, in some cases, cancer. (California Health &Safety Code Section 25249.5 et seq.) Battery posts, terminals and related accessories contain leadand lead compounds, chemicals known to the State ofCalifornia to cause cancer and birth defects or otherreproductive harm. Wash hands after handling.For Gasoline Engines: Engine exhaust contains chemicals known to the State ofCalifornia to cause cancer, birth defects, or other reproductiveharm.For Diesel Engines: Diesel engine exhaust and some of its constituents are knownto the State of California to cause cancer, birth defects, andother reproductive harm.155 095 Page 41-5. Principal Safety StandardsSafety in Welding, Cutting, and Allied Processes, ANSI Standard Z49.1,from Global Engineering Documents (phone: 1-877-413-5184, website:www.global.ihs.com).Recommended Safe Practices for the Preparation for Welding and Cut-ting of Containers and Piping, American Welding Society StandardAWS F4.1 from Global Engineering Documents (phone:1-877-413-5184, website: www.global.ihs.com).National Electrical Code, NFPA Standard 70, from National Fire Protec-tion Association, P.O. Box 9101, 1 Battery March Park, Quincy, MA022699101 (phone: 6177703000, website: www.nfpa.org).Safe Handling of Compressed Gases in Cylinders, CGA Pamphlet P-1,from Compressed Gas Association, 1735 Jefferson Davis Highway,Suite 1004, Arlington, VA 222024102 (phone: 7034120900, web-site: www.cganet.com).Code for Safety in Welding and Cutting, CSA Standard W117.2, fromCanadian Standards Association, Standards Sales, 178 RexdaleBoulevard, Rexdale, Ontario, Canada M9W 1R3 (phone:8004636727 or in Toronto 4167474044, website: www.csain-ternational.org).Practice For Occupational And Educational Eye And Face Protection,ANSI Standard Z87.1, from American National Standards Institute, 11West 42nd Street, New York, NY 100368002 (phone: 2126424900,website: www.ansi.org).Standard for Fire Prevention During Welding, Cutting, and Other HotWork, NFPA Standard 51B, from National Fire Protection Association,P.O. Box 9101, 1 Battery March Park, Quincy, MA 022699101 (phone:6177703000, website: www.nfpa.org).OSHA, Occupational Safety and Health Standards for General Indus-try, Title 29, Code of Federal Regulations (CFR), Part 1910, Subpart Q,and Part 1926, Subpart J, from U.S. Government Printing Office, Super-intendent of Documents, P.O. Box 371954, Pittsburgh, PA 15250 (thereare 10 Regional Officesphone for Region 5, Chicago, is3123532220, website: www.osha.gov).1-6. EMF InformationConsiderations About Welding And The Effects Of Low FrequencyElectric And Magnetic FieldsWelding current, as it flows through welding cables, will cause electro-magnetic fields. There has been and still is some concern about suchfields. However, after examining more than 500 studies spanning 17years of research, a special blue ribbon committee of the NationalResearch Council concluded that: The body of evidence, in thecommittees judgment, has not demonstrated that exposure to power-frequency electric and magnetic fields is a human-health hazard.However, studies are still going forth and evidence continues to beexamined. Until the final conclusions of the research are reached, youmay wish to minimize your exposure to electromagnetic fields whenwelding or cutting.To reduce magnetic fields in the workplace, use the followingprocedures:1. Keep cables close together by twisting or taping them.2. Arrange cables to one side and away from the operator.3. Do not coil or drape cables around your body.4. Keep welding power source and cables as far away from opera-tor as practical.5. Connect work clamp to workpiece as close to the weld as possi-ble.About Pacemakers:Pacemaker wearers consult your doctor before welding or going nearwelding operations. If cleared by your doctor, then following the aboveprocedures is recommended.155 095 Page 5SECTION 2 PRINCIPLES OF SHIELDED METAL ARCWELDING (SMAW)Shielded Metal Arc Welding (SMAW) or Stick welding is a process which melts and joins metals by heating them withan arc between a coated metal electrode and the workpiece. The electrode outer coating, called flux, assists in creat-ing the arc and provides the shielding gas and slag covering to protect the weld from contamination. The electrodecore provides most of the weld filler metal.When the electrode is moved along the workpiece at the correct speed the metal deposits in a uniform layer calleda bead.The Stick welding power source provides constant current (CC) and may be either alternating current (AC) or directcurrent (DC), depending on the electrode being used. The best welding characteristics are usually obtained using DCpower sources.The power in a welding circuit is measured in voltage and current. The voltage (Volts) is governed by the arc lengthbetween the electrode and the workpiece and is influenced by electrode diameter. Current is a more practical measureof the power in a weld circuit and is measured in amperes (Amps).The amperage needed to weld depends on electrode diameter, the size and thickness of the pieces to be welded,and the position of the welding. Generally, a smaller electrode and lower amperage is needed to weld a small piecethan a large piece of the same thickness. Thin metals require less current than thick metals, and a small electroderequires less amperage than a large one.It is preferable to weld on work in the flat or horizontal position. However, when forced to weld in vertical or overheadpositions it is helpful to reduce the amperage from that used when welding horizontally. Best welding results areachieved by maintaining a short arc, moving the electrode at a uniform speed, and feeding the electrode downwardat a constant speed as it melts.More specific information on the Stick welding procedure is provided in the following sections.1 Stick Welding Power Source Constant Current (CC), ACOr DC2 Insulated Electrode Holder3 Workpiece4 Work ClampRef. 157 858123 4155 095 Page 6SECTION 3 SHIELDED METAL ARC WELDING (SMAW)PROCEDURE3-1. Typical Stick Welding Set-Up Welding current starts as soon aselectrode touches the workpiece.1 WorkpieceMake sure workpiece is clean beforewelding.2 Work ClampPlace as close to the weld as possible.3 ElectrodeBefore striking an arc, insert an electrodein the electrode holder. A small diameterelectrode requires less current than alarge one. Follow recommendations ofthe electrode manufacturer when settingweld amperage (see Section 3-2).4 Insulated Electrode Holder5 Electrode Holder Position6 Arc LengthArc length is the distance from the elec-trode to the workpiece. A short arc withcorrect amperage will give a sharp,crackling sound. Correct arc length is re-lated to electrode diameter. Examine theweld bead to determine if the arc lengthis correct.Arc length for 1/16 and 3/32 in diameterelectrodes should be about 1/16 in (1.6mm); arc length for 1/8 and 5/32 in elec-trodes should be about 1/8 in (3 mm).7 SlagUse a chipping hammer and wire brush toremove slag. Remove slag and checkweld bead before making another weldpass. 151 59314352Tools Needed:76155 095 Page 73-2. Electrode And Amperage Selection ChartRef. S-087 985-A3/321/85/323/167/321/41/165/643/321/85/323/167/321/43/321/85/323/167/321/43/321/85/323/167/321/43/321/85/323/167/321/43/321/85/323/163/321/85/326010&60116013701470187024Ni-Cl308L50 100150200250300350400450ELECTRODEDC*ACPOSITIONPENETRATIONUSAGEMIN. PREP, ROUGHHIGH SPATTERGENERALSMOOTH, EASY,FASTLOW HYDROGEN,STRONGSMOOTH, EASY,FASTERCAST IRONSTAINLESSDEEPDEEPLOWMEDLOWLOWLOWLOWALLALLALLALLALLFLATHORIZFILLETALLALLEPEPEP,ENEP,ENEPEP,ENEPEP601060116013701470187024NI-CL308L*EP = ELECTRODE POSITIVE (REVERSE POLARITY) EN = ELECTRODE NEGATIVE (STRAIGHT POLARITY)ELECTRODEAMPERAGERANGEDIAMETER155 095 Page 83-3. Striking An Arc Scratch Start Technique Welding current starts assoon as electrode touches theworkpiece. The scratch-start technique ispreferred for ac welding.1 Electrode2 Workpiece3 ArcDrag electrode across workpiecelike striking a match; immediately liftelectrode slightly after touchingwork. If arc goes out, electrode waslifted too high. If electrode sticks toworkpiece, use a quick twist to free it.S-00491233-4. Striking An Arc Tapping TechniqueS-0049 Welding current starts assoon as electrode touches theworkpiece.1 Electrode2 Workpiece3 ArcBring electrode straight down toworkpiece; then lift slightly to startarc. If arc goes out, electrode waslifted too high. If electrode sticks toworkpiece, use a quick twist to free it.132155 095 Page 93-5. Positioning Electrode HolderS-066090 9010- 304545End View Of Work Angle Side View Of Electrode AngleEnd View Of Work Angle Side View Of Electrode Angle10- 30Fillet WeldsGroove WeldsAfter learning to start and hold anarc, practice running beads of weldmetal on flat plates using a full elec-trode.Hold the electrode nearly perpen-dicular to the work, although tiltingit ahead (in the direction of travel)will be helpful. To produce the best results,hold a short arc, travel at a uni-form speed, and feed the elec-trode downward at a constantrate as it melts.Direction Of WeldingDirection Of Welding155 095 Page 103-6. Electrode Movement During Welding A single stringer bead is satisfac-tory for most narrow groove weldjoints; however, for wide grooveweld joints or bridging across gaps,a weave bead or multiple stringerbeads work better.1 Stringer Bead Steady Move-ment Along Seam2 Weave Bead Side To SideMovement Along Seam3 Weave PatternsUse weave patterns to cover a widearea in one pass of the electrode. Limitweave width to a maximum of 2-1/2times diameter of electrode.S-0054-A123NotesWork like a Pro!Pros weld and cutsafely. Read thesafety rules atthe beginningof this manual.155 095 Page 113-7. Conditions That Affect Weld Bead ShapeIMPORTANT: Weld bead shape is affected by electrode angle, arc length, travel speed, and thickness of base metal.S-0661Too Slow Normal10 - 30DragToo Short Normal Too LongSpatterAngle Too Small Angle Too LargeCorrect AngleToo FastElectrode AngleArc LengthTravel Speed155 095 Page 123-8. Poor Weld Bead Characteristics1 Large Spatter Deposits2 Rough, Uneven Bead3 Slight Crater DuringWelding4 Bad Overlap5 Poor PenetrationS-0053-A542 313-9. Good Weld Bead Characteristics1 Fine Spatter2 Uniform Bead3 Moderate Crater DuringWeldingWeld a new bead or layer for each1/8 in (3.2 mm) thickness in metalsbeing welded.4 No Overlap5 Good Penetration Into BaseMetalS-0052-B152 3 4155 095 Page 133-10. Typical Weld Joints804 248Vertical Position Welds Overhead Position WeldsFlat Position Welds Horizontal Position WeldsTee JointButt JointLap Joint Tee JointButt JointLap JointTee JointButt JointLap Joint Tee JointButt JointLap Joint155 095 Page 143-11. Welding Butt JointsTypes Of Butt Joint Welds1 Tack WeldsPrevent butt joint distortion by tack weld-ing the materials in position before finalweld.Workpiece distortion occurs when heatis applied locally to a joint. One side of ametal plate will curl up toward the weld.Distortion will also cause the edges of abutt joint to pull together ahead of theelectrode as the weld cools.2 Square Groove Weld3 Single V-Groove Weld4 Double V-Groove WeldMaterials up to 3/16 in (5 mm) thick canoften be welded without special prepara-tion using the square groove weld. How-ever, when welding thicker materials itmay be necessary to prepare the edges(V-groove) of butt joints to ensure goodwelds.The single or double V-groove weld isgood for materials 3/16 3/4 in (5-19mm) thick. Generally, the single V-groove is used on materials up to 3/4 in(19 mm) thick and when, regardless ofthickness, you can weld from one sideonly. Cut the bevel with oxyacetylene orplasma cutting equipment. Removescale from material after cutting. A grind-er can also be used to prepare bevels.Create a 30 degree angle of bevel on ma-terials in V-groove welding.Butt Joint Training ProcedurePractice welding butt joints on 1/8 in (4mm) or thicker material. (Avoid thinnermaterials since they require greaterskill.) Separate the squared edges of thematerial about 1/16 in (1.6 mm) andmake a butt weld all the way through witha 1/8 in electrode. (You may need to ad-just the weld current and travel speed toobtain the desired weld.) Perform a simi-lar exercise on 1/4 in (6 mm) material, de-positing a bead on each side of the jointand fusing one to the another (no bevelneeded).Practice making a single V-groove weldon 1/4 in (6 mm) plate beveled 30. Startwith a 1/8 in electrode for the first beadand finish with a 5/32 in (4 mm) elec-trode. Be sure to penetrate about 1/32 in(1 mm) beyond the bottom of the V orroot. Perform a similar exercise on thick-er materials. Generally, deposit a beadfor each 1/8 in (3mm) of material thick-ness, cleaning the joint between layers.On heavier plates, it may be necessaryto weave the top layers to fill the groove.After completing the practice welds, testthem as described in Section 3-18.S-066230211/16 in.(1.6 mm)3 4155 095 Page 153-12. Welding Tee Joints1 Electrode2 Fillet WeldKeep arc short and move at definiterate of speed. Hold electrode asshown to provide fusion into thecorner. Square edge of the weldsurface.For maximum strength weld bothsides of upright section.3 Multi-Layer DepositsWeld a second layer when a heavi-er fillet is needed. Use any of theweaving patterns shown in Section3-6. Remove slag before makinganother weld pass.45Or LessS-0060 / S-0058-A / S-0061121323-13. Welding Lap Joints1 Electrode2 Single-Layer Fillet WeldMove electrode in circular motion.3 Multi-Layer Fillet WeldWeld a second layer when a heavi-er fillet is needed. Remove slag be-fore making another weld pass.Weld both sides of joint for maxi-mum strength.30Or LessS-0063 / S-0064Single-Layer Fillet WeldMulti-Layer Fillet Weld30Or Less1123155 095 Page 163-14. Welding Horizontal Beads And Butt Joints When welding horizontally,gravity may distort the mol-ten metal. This technique is notsuitable for all electrodes.1 Electrode2 Backing StripBevel edges if warranted by ma-terial thickness (see Section3-11). Tack weld a backing stripto the plates to make the firstweld pass (root pass) easier.804 26030Direction OfWelding45902Direction OfWeldingTilt Electrode 15 InDirection Of TravelMake First Weld Pass (Root Pass). Make Second Weld Pass.Completed Weld.Make Third Weld Pass.Bevel Material If Necessary (See Section 3-11).Single Pass HorizontalButt Joint Weld Or FirstPass Of Multi-Layer DepositSingle Pass Bead WeldDirection Of WeldingTilt Electrode 15Toward DirectionOf Welding.15909013030Direction OfWelding155 095 Page 173-15. Welding Vertical Beads And Butt Joints When welding vertically,gravity may distort the mol-ten metal. This technique is notsuitable for all electrodes.1 Electrode2 Backing StripWeld vertically by carrying theweld upward or starting at the topand welding down. Welding up-ward is easier and is shown inthese illustrations.Bevel edges if warranted by ma-terial thickness (see Section3-11). Tack weld a backing stripto the plates to make the firstweld pass (root pass) easier.804 260Single Pass Bead WeldSingle Pass Vertical Butt Joint Weld OrFirst Pass Of Multi-Layer DepositVertical Butt Joint Weld Subsequent Layers1/2 in(12 mm)Whipping UpMotionWeave Bead1/2 in (12 mm)WideDirection OfWelding Direction OfWelding90Direction OfWelding9090Direction OfWeldingArrows Show Lifting UpOf Electrode And ReturnTo Crater.ORDirection OfWelding4th Pass1st Pass2nd Pass3rd PassHesitate With Slight Up AndDown Motion.Shorten Arc AtArrowheadsWhen At CenterOf Weld.21155 095 Page 183-16. Welding Vertical Tee Joints And Lap Joints When welding vertically,gravity may distort the mol-ten metal. This technique is notsuitable for all electrodes.For maximum strength, weldboth sides of joint.804 260ORDirection OfWeldingDirection OfWeldingDirection OfWeldingArrows Show Lifting UpOf Electrode And Return ToCrater.ShowsWeavingMotion.ShowsWeavingMotion.Tee Joint WeldLap Joint WeldShowsWeavingMotion.9090 909090First Weld PassSubsequent Weld PassesDirection OfWelding155 095 Page 193-17. Welding Overhead Butt Joints And Tee Joints When welding overhead,gravity may distort the mol-ten metal. This technique is notsuitable for all electrodes.1 Electrode2 Backing StripWelding overhead is the most dif-ficult welding skill to master.When welding overhead, use awelding motion that draws arcout and slightly away from thecrater to allow weld puddle to so-lidify.When weaving is necessary, usethe pattern shown.Bevel edges if warranted by ma-terial thickness (see Section3-11). Tack weld a backing stripto the plates to make the firstweld pass (root pass) easier.804 2601/2 in (12 mm)90159030Direction OfWelding1/2 in(12 mm)1/2 in(12 mm)Direction OfWeldingElectrode PositionDirection Of WeldingWelding Patterns21Butt Joint WeldTee Joint WeldDraw arc out and awayfrom crater to let weldpuddle soldify.Overhead Welding Technique12 3Sequence Of Multiple Weld PassesFirst Weld Pass Subsequent Weld Passes155 095 Page 203-18. Weld Test1 Vise2 Weld Joint3 HammerStrike the weld joint in the directionshown. A good weld bends over butdoes not break.If the weld breaks, examine it to de-termine the cause.If the weld is porous (many holes),the arc length was probably toolong.If the weld contains bits of slag, thearc may have been too long or theelectrode was moved incorrectlywhich allowed molten slag to betrapped in the weld. This may hap-pen on a V-groove joint made inseveral layers and calls for addi-tional cleaning between layers.If the original beveled surface is vis-ible the material was not fully meltedwhich is often caused by insufficientheat or too fast a travel speed.S-0057-B2 To 3 in.1/4 in.3212 To 3 in.321(51-76 mm)(6.4 mm)(51-76 mm)SECTION 4 WELDING TROUBLESHOOTING4-1. PorosityPorosity small cavities or holesresulting from gas pockets in weldmetal.Possible Causes Corrective ActionsArc length too long. Reduce arc length.Workpiece dirty. Remove all grease, oil, moisture, rust, paint, coatings, slag, and dirt from work surface before welding.Damp electrode. Use dry electrode.155 095 Page 214-2. Excessive SpatterExcessive Spatter scattering ofmolten metal particles that cool tosolid form near weld bead.Possible Causes Corrective ActionsAmperage too high forelectrode.Decrease amperage or select larger electrode.Arc length too long or voltagetoo high.Reduce arc length or voltage.4-3. Incomplete FusionIncomplete Fusion failure of weldmetal to fuse completely with basemetal or a preceeding weld bead.Possible Causes Corrective ActionsInsufficient heat input. Increase amperage. Select larger electrode and increase amperage.Improper welding technique. Place stringer bead in proper location(s) at joint during welding.Adjust work angle or widen groove to access bottom during welding.Momentarily hold arc on groove side walls when using weaving technique.Keep arc on leading edge of weld puddle.Workpiece dirty. Remove all grease, oil, moisture, rust, paint, coatings, slag, and dirt from work surface before welding.4-4. Lack Of PenetrationLack Of Penetration shallowfusion between weld metal andbase metal.Lack of Penetration Good PenetrationPossible Causes Corrective ActionsImproper joint preparation. Material too thick. Joint preparation and design must provide access to bottom of groove.Improper weld technique. Keep arc on leading edge of weld puddle.Reduce travel speed.Insufficient heat input. Increase amperage. Select larger electrode and increase amperage.155 095 Page 224-5. Excessive PenetrationGood PenetrationExcessive Penetration weld metalmelting through base metal andhanging underneath weld.Excessive PenetrationPossible Causes Corrective ActionsExcessive heat input. Select lower amperage. Use smaller electrode.Improper weld technique. Adjust travel speed.4-6. Burn-ThroughBurn-Through weld metal meltingcompletely through base metalresulting in holes where no metal re-mains.Possible Causes Corrective ActionsExcessive heat input. Select lower amperage. Use smaller electrode.Increase and/or maintain steady travel speed.4-7. Waviness Of BeadWaviness Of Bead weld metal thatis not parallel and does not coverjoint formed by base metal.Possible Causes Corrective ActionsUnsteady hand. Use two hands. Practice technique.4-8. DistortionDistortion contraction of weld met-al during welding that forces basemetal to move.Base metal movesin the direction of the weld bead.Possible Causes Corrective ActionsExcessive heat input. Use restraint (clamp) to hold base metal in position.Make tack welds along joint before starting welding operation.Predict anticipated weld distortion and precamber base metal.Select lower amperage for electrode.Increase travel speed.Weld in small segments and allow cooling between welds.Notes16 Gauge (.063 in)22 Gauge (.031 in)24 Gauge (.025 in)20 Gauge (.037 in)18 Gauge (.050 in)14 Gauge (.078 in)1/8 in (.125 in)3/16 in (.188 in)1/4 in (.25 in)5/16 in (.313 in)3/8 in (.375 in)1/2 in (.5 in)MATERIAL THICKNESS REFERENCE CHARTNotesWork like a Pro!Pros weld and cutsafely. Read thesafety rules atthe beginningof this manual.NotesOver 80,000 trainedsince 1930!400 Trade Square East, Troy, Ohio 453731-800-332-9448 www.welding.orgStart Your ProfessionalWelding Career Now!PRINTED IN USA 2005 Miller Electric Mfg. Co. 1/05Miller Electric Mfg. Co.An Illinois Tool Works Company1635 West Spencer StreetAppleton, WI 54914 USAInternational HeadquartersUSAUSA Phone: 920-735-4505 Auto-AttendedUSA & Canada FAX: 920-735-4134International FAX: 920-735-4125European Headquarters United KingdomPhone: 44 (0) 1204-593493FAX: 44 (0) 1204-598066www.MillerWelds.com

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