Page 91 - Industrial Plants

flexibility and to minimize the need of further civil the hydraulic stability of the SPMT trailers during
works enroute, turntables were used over two the transport of the stacked modules from the
independent sets of SPMTs of 48axle lines with stacking area to their foundations. It must be
four PPUs in 4-file open compound configuration. highlighted/It is pivotal/important to highlight that
Furthermore grounding and installation at site every module featured unique dimensions and
proved to be particularly demanding due to the weights together with a varying number of
combination of cargo weight, ground conditions, supporting beams, ranging from three to eight
limited space at site and the daunting environmental beams. Even if the modules were of identical size,
factors of Southern Iraq. Hereby the installation the beam count differed in span length of the
and pre-assembly of 99 heavy modules with unit beams. As a consequence, the transportation
dimensions up to 47.50 meters of length, 15.00 process necessitated a tailored approach for each
meters of width and 13.80 meters of height and stacked module and for each haul from stacking
weighing up to 672 tons each posed a series of area to foundation the SPMT axles had to be
unique challenges, each demanding careful rearranged accordingly. This dynamic approach
consideration and strategic planning. ensured that the trailers were adjusted to support
The installation of these heavy modules was the beams of each module accurately.
divided into two categories. The first and relatively The installation and stacking procedure began
simple category comprised of modules which with lifting the lower modules to above ground
were to be installed without stacking, while the level using SPMT trailers. Once elevated to the
second category consisted of the stacking of maximum reach of the SPMTs, the modules were
lower and upper modules in two tiers at the final carefully positioned onto custom-designed stools.
installation area, with module pairs reaching Subsequently, the trailer was lowered and released
dimensions up to 28.30 meters of height and 821 under the module. Cruciform steelworks were
tons of weight. These stacking operations required strategically placed over the trailer and again the
enormous precision, as the fabrication standards SPMTs jacked up the modules to their maximum
of the modules did not allow tilting of more than 2° elevation. This cycle continued and gradually
and as the installation only allowed a 30 mm increased the modules clearance until sufficient
tolerance. Furthermore the single installation space was achieved to assemble their legs.
positions of the 99 heavy modules were to be
found in different locations on site with varying “By leveraging innovative techniques
distances. Applying a conventional stacking and equipment, the construction
method would have required the employment of a teams were able to effectively
heavy duty crawler crane at each of these overcome the unique challenges
locations. However, this method would have posed by the handling of these
limited drastically the site construction progress, components in the unforgiving
as the crane would have to be relocated each time conditions of the Iraqi desert
for every single unit installation. Considering the
time to dismantle and reassemble the crane for Subsequently, lifting the upper modules from the
each lift this traditional method would have top side with CJ ICM’s 1,600 tons crawler crane at
consumed too much time and would have had a the designated stacking area also came with
negative impact on the project. In order to avoid different challenges. The upper modules were
these interruptions given the already demanding lifted vertically from each lifting eye, differing from
schedule, engineers from both CJ ICM and JGC six to 16 lifting points per unit with two lifting eyes
developed a method using SPMT trailers and for each supporting beam. A load-spreading lifting
installing by jacking down the modules from the frame between the module and the crane’s hook
trailers directly onto their final foundations. In order was used. Due to varying dimensions and weights
to avoid relocating the crane for each lift, it was of the modules a standard single lifting frame with
decided to stack the modules in a designated area fixed dimensions could not have been utilized.
of the job site and then move the two-tier stacked This was overcome by building a customized
modules by SPMT trailers to their respective lifting frame for this project, which could be
foundations. Needless to say, distance between configured prior to each lift by adjusting the length
the center of gravity of these stacked modules from 11.40 meters to 47.50 meters and the
and the trailer increased significantly compared to frame’s width from 9.00 meters to 15.50 meters.
moving just the lower or upper module singularly. This tailor made lifting frame alone weighed 240
Consequently one of the main targets of the tons.
engineers and operators was to carefully maintain As already mentioned, the modules could not be

IndustrIal Plants - May 2024
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