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D. Mishra et al.
shielded metal arc welding technique (SMAW). However, the stability of the arc was
still a problem. SMAW utilizes an electrode, which melts together with the metals
to be joined forming a weld pool. It is popular in construction industries because of
its applicability in any working condition, unless, it is protected from rain, sand and
snow. The disadvantages of the process lie with the frequent change of electrodes
during the process, which might induce several welding defects.
8.2.3 Industry 3.0 – the Third Industrial Revolution
The next revolution in the industrial scenario came into picture with the creation of
a breakthrough machine called the computer. This computer was an analog decimal
machine in its earliest form. This later got transformed into a fully-working computer
with each passing generation, which ultimately led to the inception of concept of
“computer integrated manufacturing” (CIM). The fusion of manufacturing system
with electronic components and information technology led to the third revolution. This further reduced the labour intervention by automation of manufacturing
processes [8]. The usage of computers for programming, planning and control of
manufacturing operations increased the efficiency and effectiveness of the factories.
In this era, the problem of stabilizing the arc in the process of welding was
achieved by the invention of metal electrode coated with a thin layer of lime [9].
One outstanding achievement of this era was the invention of the resistance welding
method which led to development of other methods of joining like projection welding,
spot welding, seam welding and flash butt welding. This was followed by the invention of the thermite welding technique. The gas tungsten arc welding (GTAW) was
also introduced in this era, where the arc is delivered by tungsten, a metal which
melts at very high temperature; thus, it is not consumed in the process. To fill the
metals to be joined, a suitable filler material is utilized.
The gas metal arc welding technique (GMAW) came next which replaced the
GTAW technique. The GMAW technique utilizes a spool of wire which acts as the
electrode. This wire gets fused with the metals to be joined. The advantages of this
technique include the constant spool of wire which eliminates the frequent change
of electrodes as in SMAW, and also the feeding of a filler material as in GTAW. The
technique became popular and was employed for welding of non-ferrous metals and
steels owing to the higher deposition rate. However, the concern remained with the
inert gases such as helium and argon, which were expensive.
Later, the same welding technique was successfully reported with an environment
containing carbon dioxide gas and resulted in the short-circuit arc. Another addition
was the use of oxygen along with the inert gas which introduced the spray-type
arc transfer. The latter was the pulsed current, which allowed current variation. The
plasma arc welding technique was also invented in this era, where the arc was made
to pass via an orifice, making the arc concentrated and creating a plasma. It was
utilized for metal spraying and cutting, as the temperature was found to be higher
than that of the tungsten arc. The electron beam welding technique also got invented
D. Mishra et al.
shielded metal arc welding technique (SMAW). However, the stability of the arc was
still a problem. SMAW utilizes an electrode, which melts together with the metals
to be joined forming a weld pool. It is popular in construction industries because of
its applicability in any working condition, unless, it is protected from rain, sand and
snow. The disadvantages of the process lie with the frequent change of electrodes
during the process, which might induce several welding defects.
8.2.3 Industry 3.0 – the Third Industrial Revolution
The next revolution in the industrial scenario came into picture with the creation of
a breakthrough machine called the computer. This computer was an analog decimal
machine in its earliest form. This later got transformed into a fully-working computer
with each passing generation, which ultimately led to the inception of concept of
“computer integrated manufacturing” (CIM). The fusion of manufacturing system
with electronic components and information technology led to the third revolution. This further reduced the labour intervention by automation of manufacturing
processes [8]. The usage of computers for programming, planning and control of
manufacturing operations increased the efficiency and effectiveness of the factories.
In this era, the problem of stabilizing the arc in the process of welding was
achieved by the invention of metal electrode coated with a thin layer of lime [9].
One outstanding achievement of this era was the invention of the resistance welding
method which led to development of other methods of joining like projection welding,
spot welding, seam welding and flash butt welding. This was followed by the invention of the thermite welding technique. The gas tungsten arc welding (GTAW) was
also introduced in this era, where the arc is delivered by tungsten, a metal which
melts at very high temperature; thus, it is not consumed in the process. To fill the
metals to be joined, a suitable filler material is utilized.
The gas metal arc welding technique (GMAW) came next which replaced the
GTAW technique. The GMAW technique utilizes a spool of wire which acts as the
electrode. This wire gets fused with the metals to be joined. The advantages of this
technique include the constant spool of wire which eliminates the frequent change
of electrodes as in SMAW, and also the feeding of a filler material as in GTAW. The
technique became popular and was employed for welding of non-ferrous metals and
steels owing to the higher deposition rate. However, the concern remained with the
inert gases such as helium and argon, which were expensive.
Later, the same welding technique was successfully reported with an environment
containing carbon dioxide gas and resulted in the short-circuit arc. Another addition
was the use of oxygen along with the inert gas which introduced the spray-type
arc transfer. The latter was the pulsed current, which allowed current variation. The
plasma arc welding technique was also invented in this era, where the arc was made
to pass via an orifice, making the arc concentrated and creating a plasma. It was
utilized for metal spraying and cutting, as the temperature was found to be higher
than that of the tungsten arc. The electron beam welding technique also got invented