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1、SMAW Pipe Welding Techniques,Positions,1G 2G 5G 6G,1F 2F 2FR 4F 5F,1G Position,Pipe rotated, Electrode is always at the top Either a split bead or weave technique may be used,2G Position,Pipe Axis Vertical, Weld is Horizontal, Pipe is considered in a “fixed” position. Always use a split bead techniq
2、ue Always work from the bottom up.,5G Position,Axis of the Pipe is Horizontal, The weld in vertical. Progression may be up or down. A weave bead is best used.,6G Position,Pipe axis is fixed in position at a 45 degree incline. Thhe position includes flat, horizontal, vertical, and overhead welds. A s
3、plit bead tecvhnique is best used.,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.,2F Position,Fixed Position Best to use a split bead technique,2FR Position,Rotated,A split bead technique is
4、 best used.,4F Position,A split bead technique is best used,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.,Root Pass,Hot Pass,Fill Pass,Cover Pass,Always work from the bottom up when using the spli
5、t 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!,Always work toward the smaller side of the fillet. (It will be easier to get to) Always be careful not
6、 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!,Techniques,Stringer (push, drag, or whip), or Weave,Progression (vertical),Up deeper penetration Higher deposit rate (lb/hr) Use near 90 deg
7、ree travel angle or slightly up Down faster (point to point) less penetration for thin metal less dilution Use steep drag angle,Travel Speed,Stay on the leading edge of the puddle,Dimensions,Reinforcement Height ASME flush - 1/16 AWS flush 1/8 Reinforcement Width 1/16” past bevel edge Smooth transit
8、ion at weld toe (45o max),Keyholeing,Backing,Metallic backing ring consumable inserts,Welding grooves with Inserts,Keep the root opening wide Make the root pass in one bead Avoid tight areas at the weld toes,Welding a PJP groove,Works great for limiting restrictions inside pipes make up for loss of
9、wall on reinforcement,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.,Root Faces,Larger root faces will allow more amperage which will in turn make welding smoother and e
10、asier, as well as easier arc starts. Smaller root faces will allow more penetration.,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 interpass grind lumps off before next pass stagger all starts
11、and stops betoeen passes stagger all starts and stops between beads in a single pass Dont overgrind tacks.,Root faces - 0 450 included angle Remove all mill scales and rust Tacking - not in groove Tack away from coupon area. Flush on backing,Butt Joint Preperation,(With Backing),600 included angle R
12、oot faces Tacking Feather Tacks,Butt Joint Preperation,(Joints without backing),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
13、in front of the puddle at all times. Use the keyholing technique.,Restarts,Stagger all starts and stops or use runon, runoff tabs Feather all restarts & start on top, or start in front and remelt Dont restart in a coupon area. Also stagger all beads on a single pass. Use a longer arc length when sta
14、rting a weld.,Compare interpass grinding techniques vs. no interpass grinding.,Craters,Fill craters by welding into the previous weld start Use a short arc length to control heat.,Wagon Tracks,Watch these areas. Be sure to keep it melted into these spots.,Electrode Angles,Up Progression - always poi
15、nt toward center of Pipe Down Progression - use a steep drag angle,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.,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,
