smaw pipe welding techniques

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SMAW Pipe Welding Techniques

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Page 1: SMAW Pipe Welding Techniques

SMAWPipe WeldingTechniques

Page 2: SMAW Pipe Welding Techniques

Positions

• 1G

• 2G

• 5G

• 6G

• 1F

• 2F

• 2FR

• 4F

• 5F

Page 3: SMAW Pipe Welding Techniques

1G Position

Pipe rotated, Electrode is always at the top

Either a split bead or weave technique may be used

Page 4: SMAW Pipe Welding Techniques

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.

Page 5: SMAW Pipe Welding Techniques

5G Position

Axis of the Pipe is Horizontal, The weld in vertical.

Progression may be up or down.

A weave bead is best used.

Page 6: SMAW Pipe Welding Techniques

6G PositionPipe 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.

Page 7: SMAW Pipe Welding Techniques

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.

Page 8: SMAW Pipe Welding Techniques

2F Position

Fixed Position

Best to use a split bead technique

Page 9: SMAW Pipe Welding Techniques

2FR Position

Rotated

A split bead technique is best used.

Page 10: SMAW Pipe Welding Techniques

4F Position

A split bead technique is best used

Page 11: SMAW Pipe Welding Techniques

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.

Page 12: SMAW Pipe Welding Techniques

Root Pass Hot Pass

Fill Pass Cover Pass

Page 13: SMAW Pipe Welding Techniques

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!

Page 14: SMAW Pipe Welding Techniques

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!

Page 15: SMAW Pipe Welding Techniques

Techniques• Stringer (push, drag, or whip), or Weave

Page 16: SMAW Pipe Welding Techniques

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

Page 17: SMAW Pipe Welding Techniques

Travel Speed

• Stay on the leading edge of the puddle

Page 18: SMAW Pipe Welding Techniques

Dimensions

• Reinforcement Height– ASME flush - 1/16– AWS flush 1/8

• Reinforcement Width– 1/16” past bevel edge

• Smooth transition at weld toe (45o max)

Page 19: SMAW Pipe Welding Techniques

Keyholeing

Page 20: SMAW Pipe Welding Techniques

Backing

• Metallic– backing ring– consumable inserts

Page 21: SMAW Pipe Welding Techniques

Welding grooves with Inserts

• Keep the root opening wide

• Make the root pass in one bead

• Avoid tight areas at the weld toes

Page 22: SMAW Pipe Welding Techniques

Welding a PJP groove

• Works great for limiting restrictions inside pipes

• make up for loss of wall on reinforcement

Page 23: SMAW Pipe Welding Techniques

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.

Page 24: SMAW Pipe Welding Techniques

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.

Page 25: SMAW Pipe Welding Techniques

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 and stops betoeen passes• stagger all starts and stops between beads in a

single pass• Don’t overgrind tacks.

Page 26: SMAW Pipe Welding Techniques

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)

Page 27: SMAW Pipe Welding Techniques

600 included angle

Root faces

Tacking

Feather Tacks

Butt Joint Preperation

1/16-1/8

(Joints without backing)

Page 28: SMAW Pipe Welding Techniques

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.

Page 29: SMAW Pipe Welding Techniques

Restarts

•Stagger all starts and stops or use runon, runoff 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. no interpass grinding.

Page 30: SMAW Pipe Welding Techniques

Craters

• Fill craters by welding into the previous weld start

• Use a short arc length to control heat.

Page 31: SMAW Pipe Welding Techniques

Wagon Tracks

Page 32: SMAW Pipe Welding Techniques

Watch these areas. Be sure to keep it melted into these spots.

Page 33: SMAW Pipe Welding Techniques

Electrode Angles

• Up Progression - always point toward center of Pipe

• Down Progression - use a steep drag angle

Page 34: SMAW Pipe Welding Techniques

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.

Page 35: SMAW Pipe Welding Techniques

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