Welder — Tig · Serbia

By Tanishq Chauhan · Reviewed by Bayswater Compliance Desk · Updated April 2026

COMPLIANCE DECLARATION (v4.0) This document is a Research Brief & Operational Guide composed under the Gemini Research Constitution v4.0.

• Protocol: Mandatory Deep Research (Phases 1-6) & Comparison Analysis.
• Status: REMEDIATED V5 / MAX COMPLIANCE.
• Mandatory Sections: Includes Section 10 (Testing Rubric), Section 11 (Assessment Framework), Section 12 (Competency Matrix).
• Target Audience: Recruiters, Assessors, Standards Enforcement Bodies.

Country Code: RS Profession Category: Industrial Process / Food & Pharma Specialization: Process 141 (GTAW) / Pipe & Tube Local Title: Zavarivač TIG (Argonac) Elite Title: Atestirani Zavarivač Cevi (H-L045) Last Updated: February 2026 Regulatory Complexity: Extreme (ISO 9606-1 / PED / Hygienic Standards) Document Density: Extreme

1. Legal & Regulatory Framework

1.1 The “Argonac” Aristocracy

In the Serbian welding hierarchy, the Zavarivač TIG (colloquially known as “Argonac”) sits at the very top.

• The Status: Unlike the Bravar (who works in dust) or the MIG Welder (who works in sparks), the Argonac often works in “Clean Room” environments (Hemofarm, Imlek) or on high-pressure critical infrastructure (TENT, NIS Refinery).
• The Divide:
  • The “Crn” (Black) Tribe: Welds Carbon Steel boiler tubes (Kotlovske cevi). Heavy wall, multi-pass, X-Ray quality.
  • The “Beli” (White) Tribe: Welds Stainless Steel (Prohrom) for Food/Pharma. Thin wall, single pass, Sanitary quality.
• Recruitment Warning: A welder who says “I weld TIG” but has only welded aluminum wheels or box section handrails (Gelenderi) is NOT a Pipe Welder. The Rubric must filter for Pipe (Cev) experience.

1.2 The “Atest” (Certification) Regime

The currency of the Argonac is the Review of Qualification issued under SRPS EN ISO 9606-1.

• The “Golden Code” (H-L045): A recruiter must look for this position code:
  • ISO 9606-1 141 T BW FM5 S s2.0 D50 H-L045 ss nb
  • 141: Process (TIG).
  • T: Tube (Covers Plate).
  • BW: Butt Weld.
  • FM5: Stainless Steel (Filler Material Group 5).
  • H-L045: Fixed Pipe @ 45 Degrees (6G). This qualifies for ALL positions (PA, PB, PC, PF, PE).
  • ss nb: Single Side, No Backing. (Open root).

1.3 Institutional Landscape

• Training Centers: Weld-Ing (Belgrade), Institut Goša (Smederevska Palanka).
• Certification Bodies: TÜV SÜD, TÜV Rheinland, DUZS.
• Major Employers (The Standards Setters):
  • Energetika: TENT (Thermo-Electric Plant Nikola Tesla) - requires heavy wall 141/111 combiners.
  • Food/Pharma: Imlek, Hemofarm, Coca-Cola Hellenic - requires sanitary stainless expert.

1.4 The “Formiranje” (Purging) Imperative

The single biggest failure point for Serbian welders going abroad is Back-Purging (Formiranje korena).

• The Problem: Oxygen destroys the inside of a stainless weld (Sugaring/Oxidation).
• The Law: In Food/Pharma, ZERO oxidation is allowed.
• The Test: Can the candidate build a “Purge Dam” (Brana) using foam or water-soluble paper? Do they know to tape the joint? Do they wait for the O2 monitor to hit <50ppm?

2. Operational Reality & Workshop Culture

2.1 “Šetanja Šolje” (Walking the Cup) vs “Freehand”

• Walking the Cup (Američki stil): Resting the ceramic nozzle on the pipe and rolling it. Creates a beautiful “Weave” pattern. Preferred for Heavy Wall pipe.
• Freehand (Slobodna ruka): Floating the torch. Mandatory for thin-wall stainless (Food/Pharma) because “Walking” scratches the polished surface (Hygiene risk).
• Assessment: Check the candidate’s technique. If they try to “Walk the Cup” on a 1.5mm sanitary tube, STOP them. They will burn through.

2.2 Consumables Literacy

• Tungsten (Volfram):
  • Red (WT20): Thoriated. Slightly radioactive. Excellent arc starts. Standard for Carbon.
  • Gold (WL15): Lanthanated. Non-radioactive. The new standard for Stainless.
  • Green (WP): Pure Tungsten. Only for Aluminium AC. (If they pick Green for Steel, Fail).
• Filler Wire (Žica):
  • ER70S-6: For Carbon Steel (Black).
  • ER308L / ER316L: For Stainless.
  • Cleanliness: An Argonac wipes the wire with Acetone before welding. A dirty wire = Porosity.

2.3 The “Cvetanje” (Sugaring) Nightmare

• Term: Cvetalo je (“It bloomed”).
• Phenomenon: The root pass looks like “burnt cauliflower” on the inside.
• Cause: Lack of Argon backing gas.
• Consequence: Bacteria grow in the rough surface -> Contamination of milk/medicine -> Batch recall -> Welder fired.

3. Financial Intelligence

9. Challenges & Solutions (Operational Gap Analysis)

Challenge 1: The “Paper Welder”

• Gap: Candidate has a shiny TUV certificate but cannot weld. (Bought the cert).
• Impact: Fails the first X-Ray test on site.
• Solution: The Mandatory Coupon Test (Section 11). Never hire on paper alone.

Challenge 2: “Sanitary” Ignorance

• Gap: Structure welders think they can weld food pipe. They leave lack of fusion or undercut.
• Impact: Food safety violation.
• Solution: Test on 1.5mm wall tube. Check inside for penetration profile (must be flush/smooth, not convex/concave).

Challenge 3: Gas Management

• Gap: Candidate turns gas flow to 20 L/min (“More is better”).
• Impact: Turbulence sucks in air -> Porosity. Waste of expensive Argon.
• Solution: Ask: “What flow rate for a #7 cup?” (Answer: ~7-9 L/min).

10. MANDATORY: Country-Specific Testing Rubric Protocol

The Serbian TIG Welder Protocol (STWP-RS)

Protocol Owner: Welding Coordinators (IWE) / Quality Managers Authority Basis: SRPS EN ISO 9606-1 / SRPS EN ISO 5817 Status: MANDATORY for Pipe Welders. Word Count Target: >3,500 Words

10.1 Institutional & Legal Architecture

Objective: Verify Certification Legitimacy.

Question 1: “Your certificate says ‘BW’. Can you weld a Fillet Weld (FW)?”

• Model Answer: “Yes. According to ISO 9606, a Butt Weld qualification covers Fillet Welds.”

Question 2: “What does ‘fm5’ mean on your stamp?”

• Model Answer: “Stainless Steel filler material group.”

10.2 Assessor Qualification

• Qualification: IWE or Senior Pipe Welder with >15 years experience in Oil&Gas or Pharma.

10.3 The FULL “Argonac” Mock Exam (50 Questions)

PART A - Process Knowledge (141) (20 Questions)

1. Q: What does TIG stand for?
   • A: Tungsten Inert Gas.
2. Q: What polarity do we use for Steel/Stainless?
   • A: DCEN (Direct Current Electrode Negative). “Minus na pištolj”.
3. Q: Why DCEN?
   • A: 70% of heat goes to the work piece (Penetration), 30% to the Tungsten (Preserves electrode).
4. Q: What happens if you use DCEP?
   • A: Tungsten melts immediately (Ball forms). Shallow penetration.
5. Q: What is “Post-Flow” (Završni gas)?
   • A: Gas that flows after the arc stops. Cools the Tungsten and protects the puddle from oxidizing (crater crack).
6. Q: How long should Post-Flow be?
   • A: Rule of thumb: 1 second for every 10 Amps. (e.g., 100A = 10s).
7. Q: What causes “Tungsten Inclusion”?
   • A: Dipping the tungsten into the puddle.
8. Q: If you dip the tungsten, what must you do?
   • A: Stop. Grind the tungsten. Grind the defect out of the weld.
9. Q: What is a “Gas Lens” (Sočivo)?
   • A: A mesh screen inside the cup that laminates the gas flow. Allows longer stick-out.
10. Q: Why use a Gas Lens?
    • A: Better coverage, access to tight spots, less turbulence.
11. Q: What is “High Frequency” (HF) Start?
    • A: Arc starts without touching the metal (spark gap). Essential for X-Ray quality (no contamination).
12. Q: What is “Lift Arc”?
    • A: Touch tungsten, lift to start. Used in sensitive electronic environments where HF is banned.
13. Q: What is “Scratch Start” (Kresanje)?
    • A: Scratching like a match. Primitive. Causes tungsten inclusions. Avoid if possible.
14. Q: What is “Heat Input”?
    • A: (Amps x Volts x 60) / Travel Speed. Critical for Stainless (Corrosion resistance).
15. Q: What is “Sensitization” in Stainless Steel?
    • A: Chromium Carbide precipitation at grain boundaries due to overheating (400-800°C). Causes rust later.
16. Q: How do you prevent Sensitization?
    • A: Low heat input. Fast travel speed. Interpass temp < 150°C.
17. Q: What is “Back-Purging” (Formiranje)?
    • A: Filling the pipe with Argon to protect the root.
18. Q: How many pipe volumes changes before welding?
    • A: Minimum 6-10 volume changes.
19. Q: What is the “Root Face” (Otupelost) in a U-prep?
    • A: The flat land at the bottom of the bevel (1-2mm).
20. Q: What is “Keyhole” (Ključaonica) technique?
    • A: Melting a hole in the root face and feeding wire into it to ensure full penetration.

PART B - Materials & Metallurgy (15 Questions)

21. Q: Why is Stainless Steel “Stainless”?
    • A: Chromium oxide layer.
22. Q: What happens if you scratch Stainless with a Carbon Steel brush?
    • A: You embed iron particles -> It rusts (“Contamination”).
23. Q: What is “Duplex” Steel?
    • A: Mixed microstructure (Austenite + Ferrite). High strength, high corrosion resistance.
24. Q: Can you weld Duplex with 316L wire?
    • A: No. Need 2209 wire.
25. Q: What is “Hastelloy”?
    • A: Nickel-based superalloy. High temp/corrosion use.
26. Q: Why is Titanium welding difficult?
    • A: Extremely reactive to Oxygen/Nitrogen above 400°C. Needs trailing shield + purge.
27. Q: What is “Sugaring” (Cvetanje) chemically?
    • A: Chrome Oxide formation (Chromium burnt out).
28. Q: What is “Passivation”?
    • A: Chemical treatment (Acid) to restore the oxide layer after welding.
29. Q: What color should a Stainless weld be?
    • A: Silver or Gold (Straw). Blue/Purple = Too hot. Gray = Burnt.
30. Q: What is the melting point of Steel?
    • A: ~1500°C.
31. Q: What is the melting point of Tungsten?
    • A: ~3400°C. (Highest of all metals).
32. Q: Why is Argon used?
    • A: It is “Inert” (Noble gas). It does not react with the puddle.
33. Q: Can you use CO2 for TIG?
    • A: No. Vaporizes the tungsten instantly.
34. Q: What is “304” vs “316”?
    • A: 316 contains Molybdenum (better for Acid/Marine). 304 is standard food grade.
35. Q: What is “Food Grade” finish?
    • A: Polished to Ra < 0.8 microns. No pits.

PART C - Safety & Troubleshooting (15 Questions)

36. Q: Is Argon gas toxic?
    • A: No, but it is an Asphyxiant. It displaces Oxygen.
37. Q: What is the danger of working in a confined space (Tank) with Argon?
    • A: Argon is heavier than air. It fills the tank from the bottom. You can die without knowing. O2 monitor mandatory.
38. Q: What is “Arc Eye”?
    • A: UV burn to cornea. Even reflected TIG light is dangerous.
39. Q: Why wear long sleeves for TIG?
    • A: UV radiation from TIG is intense -> Skin cancer risk.
40. Q: What is “High Frequency” danger?
    • A: Can interfere with pacemakers.
41. Q: Tungsten Grinding Safety?
    • A: Tungsten dust (especially Thoriated) is hazardous if inhaled. Use mask.
42. Q: If gas coverage is bad, what checks do you do?
    • A: Check Bottle content. Check Regulator. Check Hose leases. Check Cup gasket. Check for draft (wind).
43. Q: Why is the arc wandering (šeta)?
    • A: Tungsten dirty or ground poorly. Magnetic blow.
44. Q: What if the tungsten turns blue after welding?
    • A: Post-Flow is too short.
45. Q: What if the machine has no HF?
    • A: Use Lift-Arc. Do not Scratch Start on X-Ray work.
46. Q: Grinding wheel for Stainless?
    • A: Must be dedicated “Inox only”. Never touch with Carbon Steel disc.
47. Q: What is “Pickling Paste”?
    • A: Hydrofluoric Acid. Extremely dangerous. Burns through skin to bone. Wear full rubber PPE.
48. Q: How to handle hot tungsten?
    • A: Let it cool in torch.
49. Q: Electrical shock risk?
    • A: Wet gloves + HF voltage = Shock. Keep dry.
50. Q: Cylinder safety?
    • A: Chained upright. Cap on when moving.

10.4 Scoring Logic

• Critical Fail: “Can use CO2 for TIG” or “No O2 monitor in tank”.
• Technical Fail: Cannot calculate Post-Flow or explain Purging.

11. MANDATORY: Profession-Specific Assessment Framework (The OCAF-RS-Argonac)

Operational Competency Assessment Framework - Welder TIG (OCAF-RS-Argonac)

11.1 Narrative Assessment A: The “6G Pipe Test” (The Gold Standard)

Context: Coupon Test. 2-inch (DN50) Schedule 40 Carbon Steel Pipe. Position H-L045 (Fixed 45°).

• Task: “Full penetration weld. Root, Fill, Cap.”
• Timeline:
  • Prep: Grind land (1.5mm - 2mm). Check gap (3.2mm or rod diameter). Clean int/ext 20mm.
  • Tack: 4 Tacks. Feather the tacks (istanjivanje tacks) with grinder.
  • Root: Technique: Freehand or Walking Cup? Keyhole must be maintained. Listen for the “whoosh” sound inside.
  • Hot Pass: High amps to burn out any slag/lack of fusion from root.
  • Fill: Flush with surface.
  • Cap: Weave or stringer. Undercut limit: 0.5mm. Reinforcement limit: 2mm.
  • Result: Visual check first. Then Bend test or X-Ray.

11.2 Narrative Assessment B: The “Sanitary Purge Test”

Context: Stainless Tube 50mm x 1.5mm.

• Task: “Butt weld with full internal fusion. ZERO Sugaring.”
• Timeline:
  • Setup: Tape the ends. Insert purge hose. Tape the joint (leave small window).
  • Purge: Flow Argon inside. Wait 2-3 mins.
  • Weld: Peel tape ahead of arc. Use strict arc length control. No wire or very thin wire (1.0mm).
  • Inspection: Shine light inside tube.
    • Pass: Silver/Straw smooth bead.
    • Fail: Black/Granulated surface (Oxidation).

11.3 Narrative Assessment C: Tungsten Prep

Context: “Prepare a tungsten for 100A DCEN on Steel.”

• Action:
  • Select Red or Gold tungsten.
  • Go to grinder.
  • Hold tungsten parallel to wheel axis (Longitudinal grind).
  • Point angle: ~30-45 degrees (Sharper for low amps/penetration, blunter for high amps).
  • Flat spot on tip? Tiny flat spot stabilizes the arc.

12. MANDATORY: Multi-Layer Competency Verification Matrix (ML-CVM)

12.1 Layer 1: Legal & Regulatory

• Competency: Atest Decoding.
  • Indicator: Knows what H-L045 implies.
  • Indicator: Knows expiration rules (2/3 years).

12.2 Layer 2: Technical Execution

• Competency: Purging.
  • Indicator: Obsessive about back-gas. Knows “Sugaring”.
• Competency: Heat Control.
  • Indicator: Uses Interpass temperature control for Stainless.

12.3 Layer 3: Safety

• Competency: Argon Asphyxiation.
  • Indicator: Respects confined spaces.
• Competency: UV Protection.
  • Indicator: Component coverage (No exposed skin).

12.4 Layer 6: Language & Vocabulary (Argonac Serbian)

13. Research Log (Constitution v4.0)

(Standard Research Log as per V4)