Page 216 - CITS - Fitter Trade Pactical - Volume - 2

FITTER - CITS

Setting the single Vee butt joint and tacking

Keep the bevel edges upside down with a root gap of 2mm, and 30 distotion allowance. (Fig 2) using suitable
support i.e. 1.50 on each side of the joint.

Fig 2

Tack-well on both ends. (20mm long)
Ensure safety apparels are worn.
Place the joint in flat position after tacking.
Deposition of root bead (Fig 3)
Deposit root bead using a Ø3.15 M.S. electrode and 110 amps welding current.

Proceed with a uniform normal speed holding a short arc.
Keep the electrode angle (as shown in Fig 3) at 800 to the line of weld.

Fig 3

Give a whipping motion to the electrode to maintain the size of the KEYHOLE for correct penetration.

Clean the root bead, and observe penetration.
Deposition of hot pass & caping beads (Fig 4)
Deposit the 1st covering bead using a 4.00mm dia medium coated M.S.electrode and 160 amps welding current.
Proceed with a uniform speed, holding a normal short arc and a side-to side weaving motion to the electrode.
Ensure the electrode angle is the same as it was for the root bead.

Clean the bead thoroughy and grind the humps in beads (if present).
Rectify possible defects, if any.

201

CITS : C G & M - Fitter - Exercise 54