Common tasks: Hands-on Skills Notes for Welder (ITI)

Common Welding Tasks – Hands‑on Skills

Program: Welder (ITI) – Subject: Hands‑on Skills – Topic: “Common Tasks”

1. Simple Explanation

In a welding shop a welder’s day is a series of routine tasks that keep a job running smoothly and safely.
These tasks include preparing the workpiece, selecting the right welding process, performing the weld, inspecting the weld and maintaining equipment.
Mastery of these steps ensures strong, defect‑free welds and a safe work environment.

2. Key Points

Task	What It Involves	Why It Matters	Typical Tools / Equipment
Joint Preparation	Cutting, beveling, cleaning, aligning, and clamping the parts.	A clean, accurately positioned joint reduces defects.	Saw, grinder, beveling jig, clamps, cleaning brushes.
Welding Process Selection	Choose MIG, TIG, Stick, Flux‑Cored, etc.	Each process suits different materials, thicknesses, and positions.	Welding machine (MIG, TIG, Stick), consumables.
Welding Execution	Set proper parameters: voltage, wire feed, travel speed, angle.	Controls heat input, penetration, and bead profile.	Welding gun, torch, electrode holder.
Weld Inspection	Visual check, non‑destructive testing (NDT), dimensional measurement.	Detects cracks, porosity, under‑penetration before part fails.	Visual inspection tools, torch, feeler gauges, NDT devices.
Post‑Weld Cleaning	Grinding, wire brushing, degreasing, rust removal.	Removes slag, burrs, and surface contaminants for future processing.	Grinder, wire brush, chemical cleaners.
Equipment Maintenance	Checking gas cylinders, cleaning nozzles, replacing filters, inspecting cables.	Prevents equipment failure and ensures safety.	Service manual, multimeter, cleaning supplies.
Safety Checks	PPE, ventilation, fire watch, gas leak test.	Protects welder and crew from injuries and accidents.	PPE kit, fire extinguisher, gas leak detector.

3. Worked Example

Scenario: MIG welding a 1 mm thick mild steel butt joint in a flat position.

Step	Action	Detail & Tip
1. Joint Prep	• Cut the steel to exact length. • Bevel edges 5° on each side. • Clean with a wire brush or solvent. • Clamp the plates together.	Tip: Use a 1 mm bevel to ensure proper penetration without excessive heat.
2. Set Up Machine	• Select MIG (GMAW) with 1 mm solid wire. • Set voltage to 25 V, wire feed 200 in/min. • Use 20 psi gas flow.	Tip: Start with lower voltage, increase if bead is too flat.
3. Weld Execution	• Hold the gun at 10° to the joint, 1 in from the root. • Move at 4–6 in/s, maintaining consistent speed. • Use a 30° weave pattern to avoid burn‑through.	Tip: Keep the torch steady; a slight back‑and‑forth weave adds filler.
4. Inspect	• Visually check for uniform bead, no porosity. • Use a feeler gauge to confirm cross‑section thickness ≥ 1.0 mm.	Tip: A 0.02 mm deviation is acceptable for 1 mm material.
5. Clean	• Lightly grind slag ridges off the weld. • Brush the seam with a wire brush.	Tip: Do not over‑grind; it can remove filler material.
6. Post‑Weld	• Record weld parameters and any observations. • Inspect for distortion and tighten clamps if needed.	Tip: Documenting helps trace any future failures.

Result: A clean, fully penetrated butt weld that meets the 1 mm thickness requirement with no visible defects.

4. Quick Revision Summary

Prepare – Cut, bevel, clean, clamp.
Select – MIG/TIG/Stick based on material & position.
Set Parameters – Voltage, wire feed, gas flow.
Execute – Proper angle, speed, weave.
Inspect – Visual, dimensional, NDT.
Clean – Grind, brush, degrease.
Maintain – Check gas, nozzles, cables.
Safety – PPE, ventilation, gas leak, fire watch.

Remember: A good weld starts with a good joint. Always follow the workflow, keep safety first, and double‑check your work before moving on.