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SMAW Welding Techniques
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Weld Bead A weld resulting from a pass Stringer Bead Weave Bead
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Passes Weld Pass - A single progression of welding along a joint. The result of a pass is a weld bead or layer
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Fill Pass Cover Pass Root Pass Hot Pass
Hot pass - one or two beads. But keep it open
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Techniques Stringer (drag) (whip) Weave Circles crescent zig zag
box weave double J
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Progression (vertical)
Up deeper penetration Higher deposit rate (lb/hr) Use near 90 degree travel angle or slightly up Down faster (point to point) less penetration for thin metal less dilution Use steep grag angle
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Travel Speed Stay on the leading edge of the puddle
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Flat Position Fillet/Groove - stringer or weave, split bead or wide weave
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Horizontal Fillet/Groove - stringers (small weave may be used in tight place) Bead Placement - bottom to top
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Vertical Fillet/Groove - weave (or whip but not straight stringers)
Root pass 6010 whip Root pass 7018 straight stringer or weave (open closed)
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Overhead Same as horizontal for Fillets
6010 open root whip for flat face and keyhole control 7018’s stringers OH Butt Joints can be stringers or weaves
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Dimensions Reinforcement -ASME flush 1/16 AWS flush 1/8 discuss keyholeing, metallic backing, nonmetallic backing, partial penetration, root openings, root faces, tacking, tack grinding, fast freeze, and fill freeze Fill -as many as needed 1/8 per pass flat overload 3/16 vertical Cover -flush 1/16 high, 1/16 past edge
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Butt Joint Preperation
(Joints without backing) 1/16-1/8 600 included angle Root faces Tacking Feather Tacks
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Open Root Technique Use root opening to allow increase in amperage for smoother welding Whip backwards for penetration Whip forwards to reduce penetration Do Not Weave a root pass. Maintain a short arc gap Stay slightly in front of the puddle at all times. Use the keyholing technique.
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Butt Joint Preperation
(With Backing) Root faces - 0 450 included angle Remove all mill scales and rust Tacking - not in groove Tack away from coupon area. Flush on backing
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Welding grooves with Backing
Keep the root opening wide Make the root pass in one bead Avoid tight areas at the weld toes
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Restarts Stagger all starts and stops or use run-on, run-off tabs
Feather all restarts & start on top, or start in front and remelt Don’t restart in a coupon area. Also stagger all beads on a single pass. Use a longer arc length when starting a weld. Compare interpass grinding techniques vs. techniques for no interpass grinding.
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Craters Fill craters by reversing direction at the weld end
Use a short arc length to control heat.
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Electrode Work Angles 700 300 450
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work angle (transverse angle)
middle of joint directs heat between sides may need to direct more on heavy plate
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Transverse Angle Effects
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Electrode Travel Angles
Drag Angle increases Penetration Increases crown height Push Angle gives shallow penetration, and flattens out the weld surface.
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Electrode (arc) Placement
Current takes the path of least resistance. Therefore, the arc, and resulting weld, will go where the electrode end is closest to, NOT NECESSARILY IN THE DIRECTION THE ELECTRODE IS POINTING
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Arc Length Longer arc lengths = increased puddle heat, flatter welds, deeper penetration Shorter arc lengths = less puddle heat, flatter welds, less penetration Use arc length to control puddle size, penetration, and burn through. Normal arc length is 1/16” - 1/8” Use a slightly longer arc length during a start or restart.
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Helpful Tips Clean your Welding Hood lens
Drape the cable over your shoulder or knee Get Comfortable Watch the puddle, not the arc Concentrate on steady travel speed and arc length
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SMAW Pipe Welding Techniques
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Positions 1G 2G 5G 6G 1F 2F 2FR 4F 5F Basic review of position designation codes. These codes will be taught in detail later.
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1G Position Pipe rotated, Electrode is always at the top
Split bead or weave technique may be used because gravity will not act to pull the puddle to one side in this position Emphasize the REASONS for choosing one technique over another Recommend progressing from one side to the other on the split bead technique. Otherwise, you increase the likelihood of undercutting in previous beads and of getting a humpy contour. Pipe rotated, Electrode is always at the top Either a split bead or weave technique may be used
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2G Position Pipe Axis Vertical, Weld is Horizontal, Pipe is considered in a “fixed” position. Always use a split bead technique Always work from the bottom up. Using a wide weave will lead to the bead sagging toward the bottom, increasing the likelihood of overlap at the bottom, and undercut at the top. Working from the bottom up gives you a shelf to work from which decreases the likelihood of entrapments Recommend using a weave technique to avoid a narrow tight area at the upper side of a pass, especially the hot pass. Explain that this tight area must be avoided. You will not often “burn it out”. You will almost always create a massive slag inclusion. Cleaning before welding will not solve it either, because new slag will go into it from flux on the electrode as you weld.
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5G Position Axis of the Pipe is Horizontal, The weld in vertical.
The weave technique is best used in vertical, F and OH doesn’t matter much. Therefore, 5G-up will best be accomplished using the weave. There is a limit on how wide you will be allowed to weave. It will depend on the code requirements, electrode side, and electrode type. Down vertical could use either, I prefer the split bead to increase travel speed stay ahead of the molten slag. Axis of the Pipe is Horizontal, The weld in vertical. Progression may be up or down. A weave bead is best used.
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6G Position Pipe axis is fixed in position at a 45 degree incline. Thhe position includes flat, horizontal, vertical, and overhead welds. A split bead tecvhnique is best used. I tend to use a split bead technique on 6G. However, if the groove is narrow, I will sometimes use a weave bead to avoid that narrow tight area at the top toe of the weld.
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1F Position Pipe is rotated. The pipe axis is at a 45 degree incline. Welding is to occur at the top of the pipe. Split bead or weave technique may be used. We tend to forget that pipe can have fillet welds too.
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2F Position Fixed Position Best to use a split bead technique
This weld is no different than a 2F fillet weld on plate.
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2FR Position A split bead technique is best used. Rotated
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A split bead technique is best used
4F Position A split bead technique is best used
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5F Position Not Rotated. Progression may be up or down.
Split beads or weaves can be used on 5F-up welds, split beads are best used on 5F-down welds.
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Fill Pass Cover Pass Root Pass Hot Pass
Hot pass - one or two beads. But keep it open. If we did end up with a tight area, it would be best to open up the area with a grinder and repair it before moving to the next pass.
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Plan your sequence of beads!
Always work from the bottom up when using the split bead technique Always be careful not to create a tight area where slag may get trapped under the next weld. It is better to weave slightly than to leave a tight area. Plan your sequence of beads!
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Plan your sequence of beads!
Always work toward the smaller side of the fillet. (It will be easier to get to) Always be careful not to create a tight area where slag may get trapped under the next weld. It is better to weave slightly than to leave a tight area. Plan your sequence of beads!
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Techniques Stringer (push, drag, or whip), or Weave
Remember, there is a reason for a particular travel or longitudinal angle. There is also a reason for a whip or a stringer technique as well as a wide weave or a split bead technique. Think ahead and use the most advantageous technique.Welding is not magic, it is careful study and forethought.
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Progression (vertical)
Up deeper penetration Higher deposit rate (lb/hr) Use near 90 degree travel angle or slightly up Down faster (point to point) less penetration for thin metal less dilution Use steep drag angle
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Travel Speed Stay on the leading edge of the puddle
Review the effects for fast and slow travel on: penetration contour width
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Keyholeing Explain How to do this technique reasons for this technique
effects of root opening and root face on heat sink why to never whip completely into the molten puddle that keyhole size determines root reinforcement width
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Root Openings Small will allow more amperage which will in turn make welding smoother and easier, as well as easier arc starts. Larger root openings will allow more penetration.
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Root Faces Larger root faces will allow more amperage which will in turn make welding smoother and easier, as well as easier arc starts. Smaller root faces will allow more penetration.
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Tacking, Tack Grinding 3/4” long feather both ends
clean and flatten tops start on top, burn through before end run completely onto tack before stopping grind lumps off before next pass stagger all starts and stops between passes stagger all starts and stops between beads in a single pass Don’t overgrind tacks.
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Butt Joint Preperation
(With Backing) Root faces - 0 450 included angle Remove all mill scales and rust Tacking - not in groove Tack away from coupon area. Flush on backing
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Butt Joint Preperation
(Joints without backing) 1/16-1/8 600 included angle Root faces Tacking Feather Tacks
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Open Root Technique Use root opening to allow increase in amperage for smoother welding Whip backwards for penetration Whip forwards to reduce penetration Do Not Weave a root pass. Maintain a short arc gap Stay slightly in front of the puddle at all times. Use the keyholing technique.
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Restarts Stagger all starts and stops or use runon, runoff tabs
Feather all restarts & start on top, or start in front and remelt Also stagger all beads on a single pass. Use a longer arc length when starting a weld.
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Craters Fill craters by welding into the previous weld start
Use a short arc length to control heat.
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Wagon Tracks
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Watch these areas. Be sure to keep it melted into these spots.
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Electrode Angles Up Progression - always point toward center of Pipe
Down Progression - use a steep drag angle
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Arc Length Longer arc lengths = increased puddle heat, flatter welds, deeper penetration Shorter arc lengths = less puddle heat, flatter welds, less penetration Use arc length to control puddle size, penetration, and burn through. Normal arc length is 1/16” - 1/8” Use a slightly longer arc length during a start or restart.
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Helpful Tips Clean your Welding Hood lens
Drape the cable over your shoulder or knee Get Comfortable Watch the puddle, not the arc Concentrate on steady travel speed and arc length
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BACK TO WELDING TERMINOLOGY
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