1. ThermexWELD Exothermic Welding User and Inspector’s Guide
“The Good-The Bad-The Ugly”
What is acceptable?
What went wrong?
How to correct.

2. ThermexWELD Exothermic Welding User and Inspector’s Guide
What went wrong?
Is it OK? OR
Must it be cut out and redone?

3. ThermexWELD Exothermic Welding User and Inspector’s Guide
ThermexWELD Exothermic Joint :
IS metallurgically fused.
IS permanent
IS electrically continuous
WILL carry more current
than the conductors
WILL NOT loosen
WILL NOT fuse
Uses PORTABLE TOOLS
requiring no outside power

4. ThermexWELD Exothermic Welding User and Inspector’s Guide
Section Through an “X” connection:
Showing the full metallurgical fusion of the conductors.

5. ThermexWELD Exothermic Welding User and Inspector’s Guide
Lets look at some practical cases:
What went wrong?
Is it OK? OR
Must it be cut out and redone?

6. ThermexWELD Exothermic Welding User and Inspector’s Guide
Mould Closure:
Some wire strands displaced from the conductor has prevented the mould closing properly.
This can happen on both vertically split or horizontally split moulds.

7. ThermexWELD Exothermic Welding User and Inspector’s Guide
Tee weld remade
Note strands neatly held.
Weld clean.
Weld nicely formed.

8. ThermexWELD Exothermic Welding User and Inspector’s Guide
Straight Connection Type SS1
Weld not formed on the top.
Cable strands exposed.
Correction:
Too LITTLE Weld Metal used.….OR
Weld metal leaked from mould.
Use CORRECT SIZE as given on Mould Tag.
NOT ACCEPTABLE as all wire strands are not welded. Remake weld.

9. ThermexWELD Exothermic Welding User and Inspector’s Guide
Straight Connection Type SS1
Weld fully formed.
Excess metal in the riser.
Correction:
Too LARGE a Weld Metal.
Use CORRECT SIZE as given on Mould Tag.
ACCEPTABLE as all wire strands are welded.

10. ThermexWELD Exothermic Welding User and Inspector’s Guide
Straight Connection Type SS1
Weld fully formed.
Slight surface slag.
Correction:
ACCEPTED
Nil required.
Acceptable surface slag up to 1 mm deep.
Tip: Check that disc is correctly seated and not dislodged when weld metal is added to crucible.

11. ThermexWELD Exothermic Welding User and Inspector’s Guide
Guide for ACCEPT/REJECT:
Correct weld form.
Small riser
Clean
No conductor exposed
ACCEPTABLE

12. ThermexWELD Exothermic Welding User and Inspector’s Guide
Guide for ACCEPT/REJECT:
Correct weld form.
Tall riser
Clean
No conductor exposed
ACCEPTABLE

13. ThermexWELD Exothermic Welding User and Inspector’s Guide
Guide for ACCEPT/REJECT:
Correct weld form
No riser
Clean
No conductor exposed
ACCEPTABLE minimum level

14. ThermexWELD Exothermic Welding User and Inspector’s Guide
Guide for ACCEPT/REJECT:
Incorrect weld form
No riser
Clean
Conductor exposed
REJECT

15. ThermexWELD Exothermic Welding User and Inspector’s Guide
MOULD TAG
Shows:
ThermexWELD Mould Code
Weld metal Size
Cable Run
Cable Tap
Gap

16. ThermexWELD Exothermic Welding User and Inspector’s Guide
Straight Connection Type SS1
Weld fully formed.
Dark surface indicates presence of oil in cable.
Slight surface porosity. (probably internal porosity as well)
Correction:
Nil required.
ACCEPTABLE.
Tip: Clean cable with solvent for next joint.

17. ThermexWELD Exothermic Welding User and Inspector’s Guide
Tee Connection Type SS2
Weld not fully formed.
Leak to sides of weld.
Slag present in top of weld.
Wires not all welded.
Correction:
Mould not correctly closed, wire in mould parting line OR
incorrect mould clamp adjustment.
Check Mould Clamp adjustment.
REJECT.

18. ThermexWELD Exothermic Welding User and Inspector’s Guide
Mould Clamp Adjustment:
Check mould closure.
Check Mould handle closing pressure:
Too tight – loosen off.
Too loose – tighten---

19. ThermexWELD Exothermic Welding User and Inspector’s Guide
Mould Handle adjustment continued:
Withdraw the R Clip in the mechanism.

20. ThermexWELD Exothermic Welding User and Inspector’s Guide
Mould Handle adjustment continued:
Screw the adjusting screw out 1 turn to make the closing “firmer”. OR
1 turn in to make the closing “softer”.
CHECK
Re-assemble and check mould closure.

21. ThermexWELD Exothermic Welding User and Inspector’s Guide
Mould Clamp adjustment continued:
After adjustment re-check the handle pressure – a “firm click” to close.

22. ThermexWELD Exothermic Welding User and Inspector’s Guide
Mould Condition:
New mould.
Crucible well defined shape.
Well defined disc seat.
Note well defined weld cavity.
Cable holes round.
New mould with correct care will make 75 to 80 connections.

23. ThermexWELD Exothermic Welding User and Inspector’s Guide
Mould Condition:
Used/Old mould.
Crucible worn.
Eroded disc seat.
Chipped and eroded weld cavity.
Cable holes worn.
Not properly cleaned after each weld.
Recommendation:
Replace mould.
Tip: Follow cleaning procedures with crucible scraper and soft brush in weld cavity.

24. ThermexWELD Exothermic Welding User and Inspector’s Guide
Good appearance:
Why does the weld appear to be “sleeved” at the ends?
Acceptable, all welds are like this!-----see next slide.

25. ThermexWELD Exothermic Welding User and Inspector’s Guide
Tee connection on steel rod shows the sleeve effect:
Hot metal has fused the rods in the centre of the joint and cooler metals flows to the side.
Acceptable weld.
No fusion at ends.
Fully fused at rods.

26. ThermexWELD Exothermic Welding User and Inspector’s Guide
Weld Type SS3
Well formed.
Fully fused.
No porosity.
All welds should be like this!

27. ThermexWELD Exothermic Welding User and Inspector’s Guide
Earth Rod Connection:
Use the T-241 clamp supplied in the Kit on ALL earth rod connections.
This clamps holds the mould in place during the welding/exothermic reaction.

28. ThermexWELD Exothermic Welding User and Inspector’s Guide
ThermexWELD Exothermic products are designed to work as a system and they may not necessarily be compatible with other manufacturer’s products.
Use ALL the correct tools.

29. ThermexWELD Exothermic Welding User and Inspector’s Guide
Weld Metal Size on the tag MUST match the Weld Metal Size on the Box and on the Container.

30. ThermexWELD Exothermic Welding User and Inspector’s Guide
ThermexWELD Exothermically Welded Joints:
Can be used on:
Copper to Copper
Copper to Steel
Copper to Copper Jacket Earth Rods
Copper to Pipes
Etc.

31. ThermexWELD Exothermic Welding User and Inspector’s Guide
For full training instructions see the ThermexWELD “TRAINING GUIDE”.
See website for a full catalogue.