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D. Sen et al.
a wide application of tubular components, such as the crash box, shock absorbers,
suspension arms, seats and instrument panel beams. According to a report published
by Arcelormittal, 40 kg of the total mass of a car comprises of the tubular components [4, 5]. Moreover, in automobile industries, there is a huge demand for light
weighting of automotive body structures so as to meet the environmental norms,
and simultaneously fulfilling the economic and safety concerns for the end-users.
Tubular components of various materials such as aluminium, magnesium, extra deep
drawing steel and advanced high strength steels are extensively used to meet these
conflicting demands. Moreover, in nuclear reprocessing plants, various important
equipment and process vessels such as vent pots, cylindrical tanks, annular tanks and
high-level waste storage tanks make use of tubular structures with high service life
[6]. Similarly, in oil and gas industries, tubes with high strengths are used to endure
the high pressure during transportation of natural gas or crude oil over long distance
[7].
These tubular components are produced by utilizing various manufacturing
processes such as centrifugal casting, mandrel mill process, tube drawing process,
extrusion and welding. The tube manufacturing industries face a lot of challenges
due to the versatility in application of tubular components in various industries. The
demand for a wide variety of shapes and sizes of the tubular products are increasing
day by day. The manufacturers face difficulty when the required shape is not the
regular one, and the size of the tube is either very small or very large. Additionally, the application of tubular components of advanced high strength steels and
titanium alloys requires special methods and manufacturing techniques to fabricate
them [8]. Finally, enhanced product quality in terms of durability, surface finish and
uniform thickness of tube with a reasonable cost is another aspect worth considering
during manufacturing of the tubular components. Therefore, to meet these challenges,
manufacturing industries are trying to utilize advanced techniques to produce quality
tubular components.
Over the past decades, a huge development has been made to master the manufacturing process of tubular components in terms of product quality, process quality,
automation, etc. Several techniques of tube manufacturing have evolved among
which two distinct processes, namely extrusion and welding are largely being utilized
by the manufacturers to produce tubular structures, as shown in Fig. 7.1 [9]. Extrusion process results in seamless tube, whereas the welding process yields in seamed
tubes. Extrusion process is a bulk metal forming process where a round cylindrical
billet is forced to move through a die and a mandrel. The die opening is of a smaller
cross-sectional area which is kept in accordance to the desired diameter of the tube
to be produced. A small clearance between the die and the mandrel is present which
is equal to the desired thickness of the tube to be formed. The interior profile of the
tube is shaped by the mandrel, while the exterior profile is shaped by the extruding
die. In extrusion process, the seamless tubes formed are homogeneous in nature, and
hence have good mechanical properties in terms of strength and corrosion resistance.
Also, extruded tubes have better pressure resistance capacity, i.e. they can withstand
high pressure, and hence are preferred in oil and gas industries. However, seamless tubes are expensive to produce and there is limitation in production of larger
D. Sen et al.
a wide application of tubular components, such as the crash box, shock absorbers,
suspension arms, seats and instrument panel beams. According to a report published
by Arcelormittal, 40 kg of the total mass of a car comprises of the tubular components [4, 5]. Moreover, in automobile industries, there is a huge demand for light
weighting of automotive body structures so as to meet the environmental norms,
and simultaneously fulfilling the economic and safety concerns for the end-users.
Tubular components of various materials such as aluminium, magnesium, extra deep
drawing steel and advanced high strength steels are extensively used to meet these
conflicting demands. Moreover, in nuclear reprocessing plants, various important
equipment and process vessels such as vent pots, cylindrical tanks, annular tanks and
high-level waste storage tanks make use of tubular structures with high service life
[6]. Similarly, in oil and gas industries, tubes with high strengths are used to endure
the high pressure during transportation of natural gas or crude oil over long distance
[7].
These tubular components are produced by utilizing various manufacturing
processes such as centrifugal casting, mandrel mill process, tube drawing process,
extrusion and welding. The tube manufacturing industries face a lot of challenges
due to the versatility in application of tubular components in various industries. The
demand for a wide variety of shapes and sizes of the tubular products are increasing
day by day. The manufacturers face difficulty when the required shape is not the
regular one, and the size of the tube is either very small or very large. Additionally, the application of tubular components of advanced high strength steels and
titanium alloys requires special methods and manufacturing techniques to fabricate
them [8]. Finally, enhanced product quality in terms of durability, surface finish and
uniform thickness of tube with a reasonable cost is another aspect worth considering
during manufacturing of the tubular components. Therefore, to meet these challenges,
manufacturing industries are trying to utilize advanced techniques to produce quality
tubular components.
Over the past decades, a huge development has been made to master the manufacturing process of tubular components in terms of product quality, process quality,
automation, etc. Several techniques of tube manufacturing have evolved among
which two distinct processes, namely extrusion and welding are largely being utilized
by the manufacturers to produce tubular structures, as shown in Fig. 7.1 [9]. Extrusion process results in seamless tube, whereas the welding process yields in seamed
tubes. Extrusion process is a bulk metal forming process where a round cylindrical
billet is forced to move through a die and a mandrel. The die opening is of a smaller
cross-sectional area which is kept in accordance to the desired diameter of the tube
to be produced. A small clearance between the die and the mandrel is present which
is equal to the desired thickness of the tube to be formed. The interior profile of the
tube is shaped by the mandrel, while the exterior profile is shaped by the extruding
die. In extrusion process, the seamless tubes formed are homogeneous in nature, and
hence have good mechanical properties in terms of strength and corrosion resistance.
Also, extruded tubes have better pressure resistance capacity, i.e. they can withstand
high pressure, and hence are preferred in oil and gas industries. However, seamless tubes are expensive to produce and there is limitation in production of larger