The document discusses underwater welding technology. It describes how underwater welding was first developed by the British Admiralty and then special waterproof electrodes were created. It discusses the different types of underwater welding including wet welding, dry welding using hyperbaric chambers, and different habitat sizes. It outlines the challenges of underwater welding including costs and equipment needs. It also discusses the welding processes, necessary equipment, safety considerations, and developing automation trends in the field.
Its a small and precise presentation about under water welding.
It cover two types of under water welding i.e. wet under water welding and dry under water welding.
i wish this small presentation help many students.....
thank you..
Electron Beam Welding is a fusion welding process in which a beam of high-velocity electrons is applied to the material to be joined. The work-piece melt as the kinetic energy of the electrons is transformed into heat upon impact. The EBW process is well-positioned to provide industries with highest quality welds and machine designs that have proven to be adaptable to specific welding tasks and production environments.
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
Welding processes have become increasingly important in almost all manufacturing industries and for structural application. 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. In this regard, it is relevant to note that a great majority of offshore repairing and surfacing work is carried out at a relatively shallow depth, in the region intermittently covered by the water known as the splash zone. Though numerically, most ship repair and welding jobs are carried out at a shallow depth, the most technologically challenging task is repair at greater depths, especially in pipelines and repair of accidental failure. The advantages of underwater welding are largely of an economic nature, because underwater-welding for marine maintenance and repair jobs by passes the need to pull the structure out of the sea and saves valuable time and dry docking costs. It is also an important technique for emergency repairs which allow the damaged structure to be safely transported to dry facilities for permanent repair or scrapping. Underwater welding is applied in both inland and offshore environments, though seasonal weather inhibits offshore underwater welding during winter. In either location, surface supplied air is the most common diving method for underwater welders. Underwater welding is an important tool for underwater fabrication works.
Underwater hyperbaric welding was invented by the Russian metallurgist Konstantin Khrenov in 1932.
Hyperbaric 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.
Its a small and precise presentation about under water welding.
It cover two types of under water welding i.e. wet under water welding and dry under water welding.
i wish this small presentation help many students.....
thank you..
Electron Beam Welding is a fusion welding process in which a beam of high-velocity electrons is applied to the material to be joined. The work-piece melt as the kinetic energy of the electrons is transformed into heat upon impact. The EBW process is well-positioned to provide industries with highest quality welds and machine designs that have proven to be adaptable to specific welding tasks and production environments.
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
Welding processes have become increasingly important in almost all manufacturing industries and for structural application. 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. In this regard, it is relevant to note that a great majority of offshore repairing and surfacing work is carried out at a relatively shallow depth, in the region intermittently covered by the water known as the splash zone. Though numerically, most ship repair and welding jobs are carried out at a shallow depth, the most technologically challenging task is repair at greater depths, especially in pipelines and repair of accidental failure. The advantages of underwater welding are largely of an economic nature, because underwater-welding for marine maintenance and repair jobs by passes the need to pull the structure out of the sea and saves valuable time and dry docking costs. It is also an important technique for emergency repairs which allow the damaged structure to be safely transported to dry facilities for permanent repair or scrapping. Underwater welding is applied in both inland and offshore environments, though seasonal weather inhibits offshore underwater welding during winter. In either location, surface supplied air is the most common diving method for underwater welders. Underwater welding is an important tool for underwater fabrication works.
Underwater hyperbaric welding was invented by the Russian metallurgist Konstantin Khrenov in 1932.
Hyperbaric 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.
Underwater welding includes a lot of different processes that join metals on offshore oil platforms, pipelines & ships .It is the process of welding under water using various techniques under various conditions.....etc.!!!
Arc welding process that produces coalescence of metals by heating them with a constricted arc between an electrode and the work piece (transferred arc) or between the electrode and the water-cooled constricting nozzle (non transferred arc) .
Plasma: A gaseous mixture of positive ions, electrons and neutral gas molecules
It is the welding process done under the water with the help of two methods : Dry Welding and Wet Welding. The presentation provides basic knowledge on the underwater welding and it's respective techniques.
Hyperbaric welding is the process in which a chamber is sealed around the structure to be welded and is filled with a gas ( He and Oxygen) at the prevailing pressure.
One of the welding processes that used in Engineering field is the electron beam welding. There are several types of welding processes similar to this, but electron beam welding has its unique features.
Thanks for the colleagues who give this slides to publish.
welding,Plasma arc welding,Plasma,,Pilot Arc ,Keyhole,Weld bead geometry ,Transferred plasma arc welding process,India,Small Part Welding
Sealed Components
Tool Die & Mold Repair
Tube Mill Welding
Long Strip Metal Welding
Non-transferred plasma arc welding process,Two Modes of operation in PAW,. Melt – In mode
Keyhole mode
conduction mode
,Effect of Various Factors on weld Quality Nozzle shape and size , Features of Plasma Arc Welding,Advantages of Plasma Arc Welding,Disadvantages of Plasma Arc Welding,Application of Plasma Arc Welding
Instability of the keyhole
Tungsten electrode set-back
Composition and flow rate of the plasma gas
Tezpur University
Underwater welding includes a lot of different processes that join metals on offshore oil platforms, pipelines & ships .It is the process of welding under water using various techniques under various conditions.....etc.!!!
Arc welding process that produces coalescence of metals by heating them with a constricted arc between an electrode and the work piece (transferred arc) or between the electrode and the water-cooled constricting nozzle (non transferred arc) .
Plasma: A gaseous mixture of positive ions, electrons and neutral gas molecules
It is the welding process done under the water with the help of two methods : Dry Welding and Wet Welding. The presentation provides basic knowledge on the underwater welding and it's respective techniques.
Hyperbaric welding is the process in which a chamber is sealed around the structure to be welded and is filled with a gas ( He and Oxygen) at the prevailing pressure.
One of the welding processes that used in Engineering field is the electron beam welding. There are several types of welding processes similar to this, but electron beam welding has its unique features.
Thanks for the colleagues who give this slides to publish.
welding,Plasma arc welding,Plasma,,Pilot Arc ,Keyhole,Weld bead geometry ,Transferred plasma arc welding process,India,Small Part Welding
Sealed Components
Tool Die & Mold Repair
Tube Mill Welding
Long Strip Metal Welding
Non-transferred plasma arc welding process,Two Modes of operation in PAW,. Melt – In mode
Keyhole mode
conduction mode
,Effect of Various Factors on weld Quality Nozzle shape and size , Features of Plasma Arc Welding,Advantages of Plasma Arc Welding,Disadvantages of Plasma Arc Welding,Application of Plasma Arc Welding
Instability of the keyhole
Tungsten electrode set-back
Composition and flow rate of the plasma gas
Tezpur University
1932 : soviet engineer Konstantin Khrenov made the first under water weld
in lab tests.
First under water welding was carried out by British Admiralty – Dockyard for
sealing leaking ships rivets below water line, in 1946.
In 1946, special waterproof electrodes were developed in Holland by
‘Van der Willingen’
A concise presentation about underwater welding. It briefly discusses about the main types, risks involved and practices involved in underwater welding
Underwater welding is an important tool for underwater fabrication works.
In 1946, special waterproof electrodes were developed in Holland by ‘Vander Willingen'’.
In recent years the number of offshore (inside the water) structures including oil drilling rigs, pipelines, platforms are being installed significantly
2. • First under water welding by British
Admiralty – Dockyard
• In 1946, special waterproof electrodes were
developed in Holland by ‘Van der
Willingen’
2
6. Hyperbaric welding is the process in which
a chamber is sealed around the structure to
be welded and is filled with a gas ( He and
Oxygen) at the prevailing pressure.
6
7. Dry welding can be of two types
•Large habitat
•Mini habitat
7
Mini habitat for underwater welding.
11. • Higher cost of process, training, etc
• Large quantity of costly and complex
equipments
• More deep, more energy requirement.
• Cant weld if weld spot is at
unreachable place
11
12. • Simply means that job is
performed directly in the water
• It involves using special rod and
is similar to the process in
ordinary air welding
12
15. • WATER-------------HYDROGEN +
OXYGEN
• Dissolve in weld pool
• Solubility decrases and then comes out -
porosity
• Oxygen as solid , liquid inclusions or
gases
• Hydrogen combines with oxygen forming
vapour
15
19. • Effect of alloying elements on weld metal
microstructure and properties
• Managanese
• Boron and titanium
• Rare earth metals
19
20. • Cheapest
• Fastest
• Tensile strength is high
• Ease of access the weld spot
• No waste of time in constructing habitat
20
21. • Rapid quenching decreases impact
strength, Ductility.
• Hydrogen embrittlement.
• Poor visibility in water.
• Higher energy density of hydrogen,
higher efficiency.
21
22. • Power supply requrements-400 amp or larger.
DC generators, motor generators and rectifiers
are acceptable power supplies
• Power converters.
• Welding Generator, Pre-Setup
• Polarity.
• Diesel Driven Welding Generator Amperage
and Voltage settings.
• Gas Manifolds.
22
25. • Hydrogen and oxygen are dissociated
from the water and will travel separately
as bubbles
• Oxygen cutting is about 60 percent
efficient
• Above river beds, especially in mud,
because trapped methane gas in the
proper concentrations can explode.
25
26. • There is a risk to the welder/diver of electric
shock.
• There is a risk that defects may remain
undetected
• The other main area of risk is to the life or
health of the welder/diver from nitrogen
introduced into the blood steam during exposure
to air at increased pressure
26
27. • Start cutting at the highest point and work
downward
• By withdrawing the electrode every few
seconds to allow water to enter the cut
• Gases may be vented to the surface with a vent
tube (flexible hose) secured in place from the
high point where gases would collect to a
position above the waterline.
27
28. • Precautions include achieving adequate
electrical insulation of the welding
equipment
• Areas and voids must be vented or made
inert
28
29. • Development of alternative welding methods
like friction welding, explosive welding, and
stud welding.
• Present trend is towards automation. THOR – 1
(TIG Hyperbaric Orbital Robot) is developed
where diver performs pipefitting, installs the
track and orbital head on the pipe and the rest
process is automated.
29