Chemical Engineering February 2016 - 56

Welding progress
Construction Business Associates, LLC
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5
Months
n Achieved n Required - Total achieved - Total required
Figure 2. Shown here is a snapshot of the remaining 12,000 welds required to complete the project, and
the actual pace of completion
of the overall capital project.
Therefore, a system of weld counts
was developed. This approach, universally
used in the construction of
large power plants, was easily applied
to this project. Since almost all
of the welds were of the same size
and wall thickness, a straightforward
count of welds sufficed, as opposed
to the concept of determining equivalent
welds.
The system was simple. Using
the design documents, most of the
15,000 welds were assigned to each
of the 14 systems and the remainder
were attributed to a category called
" common. " In this manner, as welds
were completed, one could now not
only determine the project's overall
percent complete, but also determine
the approximate state of readiness
of each of the 14 systems.
For example, let's say that each
system had approximately 1,000
welds associated with it. That then
left 1,000 welds to be assigned
to the common category. So the
agreement was that only once 7,500
welds were complete could the project
work be called 50% complete,
and this was not yet the case.
When the consultant was engaged,
a detailed weld count revealed that
only 3,000 of the 15,000 welds had
been completed - leaving 12,000
welds still to be completed. Figure
2 shows the plan for those remaining
12,000 welds over the next nine
months, and the actual progress to
the mid-point of the job.
As shown in Figure 2, 50% of the
total 15,000 welds were completed
in the fifth month of welding. Per the
earlier agreement, that then equated
to a project completion of 50%.
56
However, once a construction
project, such as this chemical plant
expansion, reaches that 50% completion
stage, the focus needs to
shift to include commissioning and
startup. In this case, it was comforting
to finally know that after 5
months of welding, approximately
half of the work effort was complete
- but this did not assure that all 14
systems would be ready for commissioning
and startup, as needed, for
the upcoming production cycle. So,
attention was shifted to determine
which of the 14 systems needed to
be ready when. The systems were
prioritized, and this effort helped to
determine exactly which welds had
to be made next.
One could now take the position
that, having established a rational
approach for measuring progress
and establishing priorities, the work
was well in hand and minimal attention
needed to be paid to the remaining
efforts of the contractor. Unfortunately,
such a position is never
prudent, and letting go of the management
details could still end up
with the project in a state of disaster.
For this real-life project, this was fortunately
recognized by all parties.
Costs
The question to be asked at this
stage of the project was whether or
not the contractor could meet the
resource requirements to get from
the current 50% to 100% within
the allotted budget, in accordance
with the restructured schedule. To
answer this question, an additional
view of the project was required
- beyond just measuring the percent
completed. The added insight
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Build transparency
The key to building transparency in a
complex expansion or revamp project is
to know:
* When to switch from measuring by discipline
to measuring by system
* How to determine progress as it relates
to work effort
* How to measure progress as it relates
to productivity
* How to measure progress as it relates
to budget
* How to determine overall project completion
required
that the percent complete
needed to be measured and plotted
against time, so that the project
could progress going forward. Figure
3 provides an example of this.
As shown in Figure 3, plotting manhours
(on the left vertical axis), and
percent complete (on the right vertical
axis) against time on the horizontal
axis, both against a planned percent-complete
curve (shown with a
black dashed line), tells an interesting
story. It shows that after 7 months,
the 14-month project is essentially at
the 50% point, just as was planned.
However, it also shows that the costs
are exceeding the budget, and actually
have been since the work was initiated.
If this were allowed to continue
without a change in course, it would
have resulted in a 20% overrun (or
greater) of the budget.
In most scenarios, this is not acceptable.
So the project team
needed to review the plans that were
in place for completing the second
half of this project.The goal was to
see if there might be alternate approaches
that would still maintain
the schedule while also maintaining
or reducing the costs and resources
required. Usually, at this stage of the
project, there are still some opportunities
to change the trajectory of the
budget projections and timelines. In
this particular project, with half of the
welding still to be completed, changing
from manual to orbital welding
provided an ideal opportunity to reduce
future costs (by reducing the
number of hours required to complete
this work).
The outcome
Ultimately, this project was completed
on time and within budget.
However, it is doubtful that outcome
would have been the result without
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Monthly welds required
Cumulative welds required

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Chemical Engineering February 2016

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