2. Pressure vessels are not like the other commonly used industrial
vessels. This is because, as the name suggest, pressure
vessels hold pressurized substances. Thus, these vessels
need to have higher mechanical and tensile strength than the
normal material holding vessels. If anything, whether gas or
liquid is compressed, then it will 'try' to force its way out
through any weakened areas. Thus, it is only a properly
designed vessel that can hold pressurized gases or liquids. In
the past, before the advancement of current technology
standards, there were many factory accidents caused by
bursting pressure vessels. However, engineering technology
has helped improve the safety and reliability of safety vessels.
3. One of the well-known technological advancements in the
design and contribution of pressure vessels is stainless
fabrication. Engineers use stainless steel for the manufacture
of pressure vessels. Steel is highly versatile, and there are
various techniques of fabricating it. Steel is very highly
malleable and can thus be spun, deep drawn, welded,
machined, folded or bent and steel has high rates of work
hardening and strength. There are three major types of
engineering technology used in stainless fabrication namely
welding, machining and work hardening.
4. Work hardening
Work hardening can be described as the process of adding
strength to stainless metal by deforming it. As compared
to the other steel types, the rate of hardening for
stainless steel work is quicker, although the exact rate of
hardening is dependent on the particular alloy grade. For
example, austenitic stainless steel has a slightly higher
rate of hardening than carbon steel, and thus is widely
used in the processes of stainless fabrication.
5. Machining
Stainless steel grades 416, 410, 430 and 303 acquire
resistance to chipping when they are alloyed (mixed) with
manganese sulphide. The decreased corrosion and
ductility resistance which comes when manganese
sulphide is added to steel, have resulted in these steel
grades have lower matching applications, although modern
engineering technology has led to the development of
various free machining grades to address this particular
problem.
6. To overcome the limits that arise when it comes to machining
some certain stainless steel types, some manufacturing
companies have adopted some exclusive techniques of
melting steel to enhance the machine-ability of the
austenitic stainless steel grades that are commonly used in
steel fabrication. These special processes can cause
improvement in the efficiency of machining and may help
enhance the life of the pressure vessel. These processes
are beneficial because of the various factors that must be
considered such as the need of chipping, the process of
matching stainless steel can be complex.
7. Welding
Most steel types can be welded for purposes of vessels
fabrication. However, the efficiency degree is dependent on
the grade of the stainless steel. The need of complying with
various pressure vessel design requirements,
manufacturers and engineers can apply one or several
methods of fabrication stainless steel.
Resources:
http://mpgia.com/blog/en/reliable-asme-pressure-vessel-fabricator/
http://ezinearticles.com/?Engineering-Technology-For-Vessel-
Fabrication&id=8177954
