Welder Training – TIG MIG ARC

WELDER TRAINING

Welder Training

Welder Training  in TIG MIG ARC – 1G to 6G position

 

Welder Certification (Without Experience)

Topics Covered:

  • Operations of SMAW / GTAW / OFGW/MIG / SAW Processes
  • Types of Joint
  • Classification of Electrodes
  • Welding Procedures
  • Welding Defects , Causes and Remedies
  • Theoretical – 10%
  • Practical – 90%

Course on GMAW Process (Mig/Mag) for Non Welders:

Topics Covered:

  • Basics of SMAW & GMAW process
  • Important welding variables of each process and their effects on welding
  • Welding techniques of each process in different positions
  • Effect of shielding gases on GMAW of Carbon steel
  • Welding Consumables
  • GMAW Steel filler wires and their codes
  • GMAW process advantages
  • GMAW process characteristics
  • Current/voltage relation in different shielding gases and their effects on metal transfer modes in GMAW process
  • Theoretical – 10%
  • Practical – 90%

Welding Technology

Topics Covered:

  • Welding Processes
  • Basic Welding Metallurgy
  • Weldability of metals-Ferrous & Non-Ferrous
  • Classification & Coding of welding electrodes
  • WPS & PQR
  • Welding Consumables
  • Weld Defects-their cause & remedies
  • Weld distortion– stress & control
  • Safety in welding
  • Theoretical – 60%
  • Practical – 40%

Foundation Course for Welders Conversant with Smaw Process

Topics Covered:

  • GMAW  Process
  • Equipment & Accessories
  • Modes of  metal transfer and industrial application
  • Selection of welding consumables
  • Weld defects – their causes & remedies
  • Welding Safety
  • Theoretical – 10%
  • Practical – 90%

High Pressure Welding on MS/SS

Topics Covered:

  • GTAW Process characteristics, its advantages & limitations
  • Power sources, equipment & accessories
  • Shielding gasses and their properties
  • Non consumable electrodes & filler metals
  • Weldability of MS & SS
  • Joint design & welding techniques
  • Theoretical – 10%
  • Practical – 90%

Reclamation Welding Technology For Welders

Topics Covered:

  • Welding Process
  • Basic Welding Metallurgy
  • Welding Consumables
  • Weldability of metals-Ferrous & Non-Ferrous
  • Weld defects –Causes and Remedies
  • Weld distortion, stress and control
  • Wear Factors and weld surfacing
  • Theoretical – 50%
  • Practical – 50%

Welding of Stainless Steel/Aluminium by Shielded Tungsten arc Welding

Topics Covered:

  • GTAW Process characteristics & its advantages
  • Power sources, equipment & their properties
  • Shielding gases and their properties
  • Selection of filler metals
  • Choice of non-consumable electrode & electrode holder
  • Joint design & welding techniques
  • Physical & chemical properties of SS & AL
  • Theoretical – 30%
  • Practical – 70%

 

 

WELD DEFECTS

WELD DEFECTS

DISCONTINUITY IN WELD DEFECTS ::

  • AN INTERUUPTION OF THE TYPICAL STRUCTURE IN THE MECHANICAL OR METALLURGICAL OR PHYSICAL CHARETERESTICS OF MATERIAL OR WELDMENT
  • DISCONTINUITY IS A DEFECT WHEN IT DOES NOT MEET THE PRODUCT REQUIREMENT

TYPES OF DEFECTS:

  • PLANAR

CRACKS, LAMELLAR TEARS

LACK OF FUSION

LACK OF PENETRATION

  • VOLUMINAR

POROSITY

SLAG

TUNGSTEN INCLUSION

INSPECTION METHOD IN  WELD DEFECTS:

JOINT RT UT PT MT VT
BUTT A A A A A
CORNER O A A A A
TEE O A A A A
LAP U O A A A
A – APPLICABLE O –   Marginally applicablity U- Not applicable

POROSTY – Types

  • SCATTERED POROSITY
  • CLUSTER POROSTY
  • LINEAR ALIGNED POROSITY
  • WORMHOLE – ELONGATED POROSTY

Porosity – Causes

  • Due to dissolved gases ( mostly H2 ) in the weld metal > the solubility limits when weld solidifies
  • H2 is supplied by gas shield, moisture in atmosphere, flux, coating, or water in the area of welding
  • Excess arc length
  • Moisture pickup in the low hydrogen electrodes
  • Surface contamination
  • Moist flux
  • Magnetic arc blow
  • Welding speed too high
  • Crater pipes
  • In TIG , MIG process loss of shielding, impure gas may causes porosity
  • More tendency in vertical & overhead position
  • At start and stop points due to unstable heat flow condition

SLAG & SOLID INCLUSIONS

  • Oxides and other non metallic solid materials entrapped between weld and base metal, or between weld metal and base metal

CAUSES

  • Loss of slag control due to poor manipulating technique and slag flooding advance of the arc because of the arc positioning
  • Incomplete inter-pass cleaning
  • Poor previous bead
  • Heavy mill scale or rust
  • Piece of unfused flux from electrodes with damaged coatings