underwater welding is the process of welding at elevated pressures, normally underwater. Hyperbaric welding can either take place wet in the water itself or dry inside a specially constructed positive pressure enclosure and hence a dry environment. It is predominantly referred to as "hyperbaric welding" when used in a dry environment, and "underwater welding" when in a wet environment. The applications of hyperbaric welding are diverse—it is often used to repair ships, offshore oil platforms, and pipelines. Steel is the most common material welded. Welding processes have become increasingly important in almost all manufacturing industries and for structural application.[5] Although a large number of techniques are available for welding in atmosphere, many of these techniques cannot be applied in offshore and marine application where presence of water is of major concern

1. UNDER WATER WELDING
MD. ADIL
14 MEB 119
S. No. 26
GG 0540

2. Outlines..
• Introduction and history
• Importance of underwater welding
• Principle of operation
• Classification
• Advantages and Disadvantages
• Risks involved and Safety
• Applications
• future Scope
• Conclusion
• Refrences
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3. Introduction and History..
Process of welding underwater or elevated pressures
 Khrenov , a Russian
engineer, In 1932
invented the under-
water welding.
 In 1946,First water proof
electrode made in Holland
by Van der Willingen
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4. Importance of Underwater welding
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5. Principle of operation..
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 Arc is an electric current flowing between two electrodes through an
ionized column of gas.

6. Continued..
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7. Classification..
 Broadly divided into two types
Dry welding Wet welding
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8. Dry welding
 water is sucked out
 Cabin is made
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9. Wet welding
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 Job is performed directly in
water

10. Advantages of wet welding
 No enclosure or cabin is required.
 Easily reachable to any type of portion.
 Minimum amount of equipment is required.
 High operating speed.
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11. Disadvantages of wet welding
 Rapid quenching reduces impact strength and ductility.
 Poor visibility due to contamination of water.
 Hydrogen embrittlement cracks.
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12. Advantages of dry welding
 Better safety of diver.
 Good quality of welds.
 No fear of shock for welder.
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13. Disadvantages of dry welding
 Higher cost of training and process.
 It cannot approach to unreachable place.
 Large quantity of heavy and costly equipments.
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14. Risks involved
 Chances of electric shock.
 Possibility of an explosion.
 Decompression sickness.
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15. Continued..
 Danger of “ delta p” pressure .
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16. Safety measures..
 Proper training
 Proper insulated suit for welder.
 Avoid formation of gas bubbles to avoid explosion.
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17. Applications.
 Repairing of pipelines.
 Oil is being extracted from a
large depth in the sea.
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Welding of pipeline

18. Continued..
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 Repairing of ships
 Maintainance of naval
objects.

19. Live video of underwater(wet) welding.
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20. Future scopes..
 Development of alternate methods like friction welding ,explosion
welding etc.
 Proceeding towards the automation
of underwater welding.
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Friction welding

21. Conclusion..
• Underwater welding is a very advanced technique. It helps up a lot in
our activities.
• But still it is needed Improvement to avoid accidents
and explosion .
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22. Refrences
 www.slideshare.net
 www.weldpedia.com
 www.wikihow.com/Weld-Underwater
 www.banglajol.info/index.php/JNAME/article/view/927/993
 www.google.com/search
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23. THANK YOU