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Types of welding fit under categories as listed here:

Gas welding
This type of welding creates a flame from a burning gas and this
creates the welding heat that is needed. You will see this in the
following types of welding:

Propane torches -- people use this when they want to sweat a joint
or when they want to solder two pieces of metal together. This is
one of the lowest heats and can be used for small things.

Oxyacetylene torch-- this heat gets a bit hotter and many people
say this is the most universal type of welding tool you can find.
This is used when you need a very hot flame. This type of torch
will weld a variety of things as long as you have the right metals
and tools for it. It is generally used when you want to cut, braze,
weld or solder something that requires a higher heat. You have to
be careful though because it is a type of heat that can be
difficult to control and it can sometimes overheat the area.

Oxy-propane -- this type of welding is used when you want to
solder, braze or heat something. This is a cheaper form of both of
the types of welding that was first listed.

Arc welding
This type of welding creates the heat through the use of an
electric arc. The types of welding that are done through this type
of welding include:

Basic AC & DC arc welders -- when you are looking for a way to weld
either heavy gauge steel or cast iron this is the type of welding
to use. It uses rods that you guide along the place to be weld and
these are made of flux coated steel or other materials.

MIG (Metal Inert Gas) -- this is a very quick way of welding and
some say it is easier to do than regular arch welding. It is done
through the use of a DC arc and it uses filler metal that is used
with a spool of thin wire. You use inert gas instead of flux. This
is usually used with steal bodywork and is a good choice when you
need to weld sheet metal.

TIG (Tungsten Inert Gas) -- this type of welding uses an AC arc
that is of high frequency and it is combined with a tungsten
electrode that is shielded by inert gas. This comes together to
create a torch that is controllable. This is a good choice to weld
very thin metals together. If you are working with aluminum or
stainless steel this is a good choice.

Courtesy: Welder World

Is there any AWS chapter so far in Pakistan? I browsed through their site and could not find any reference. It's probably very expensive to get certification trainings for welding in Pakistan. A few courses are offered by Atomic Energy, but apart from that I guess it is mostly an on job learning experience with a chosen few who manage to get professionally certified.

Also what could be the best practical way of learning about welding fundamentals, apart from the theoretical knowledge? Input from welding and inspection experts would be highly appreciated.

Hi Sim,

As you have rightly mentioned, no chapter nothing running by AWS in Pakistan. The best resource of welding knowledge and some good courses are being offered by PWI (Pakistan Welding Institute). As far as I know them, they are good and knowledgeable people. Some two years before Dr. Habibullah and Mr. Asif were running a good show from PWI conducting training on welding fundamentals and some other specific courses also. PWI personnel are good in giving you advises regarding certain welding issues, welding procedure specifications, procedure qualification records (PQRs). Some years back, we got many WPS verified from them and they qualified all of them at their location by developing PQRs which we are still using.

Regarding welding inspections, NCNDT (National Center for Non Destructive Testing) is a good organization but their working is very much limited as far as I have experienced with them. But still they help you with most of the issues regarding welding inspection techniques and offer their services also.

In addition to these companies, Moody International, SGS International are also operating in Pakistan with full strength. Sometimes, they conduct very informative and practical training courses on Welding and Inspection. Some days back I think on June 27, Moody International conducted a course in Pakistan on "Welding Inspection". They invite senior training staff from their principal who share practical welding knowledge and experience of different industries across the globe which surely broaden your knowledge.

The best way of learning about welding is to go thru those books and literature which AWS issues. AWS always releases the best practical knowledge about welding. Before to take a start, I would recommend you to freeze your scope of welding. First select the areas where you want to learn more deeply. It would be depending upon the type of industry you are belonging. If you belong to some petrochemical plants, I can help you in developing a scope about which you must start learning. Being specific in learning about welding would help you a lot otherwise, it would be a mess.

Hope this answers your query.