REFINERY PROJECT

In general, I agree with you although I don’t think w is necessar and I can’t see any use of P, even though it is easy to calculate.

Do you disagree with this:

P = Σ(p x w)

= p1w1 + p2w2 + p3w3 ...

where (Total Project Hours) is a common denominator

So

P = (Σ(p x Estimated Task Hours))/(Total Project Hours)

... and w doesn’t come into it.



Suppose 2 Tasks:



p1 = 30/100, Work = 40 Hours

P2 = 60/100, Work = 60 Hours



This is all that is needed to calculate P:



P x (Total Project Hours) = ((30 x 40)/100) + ((60 x 60)/100)



P = (12 + 36)/(40 + 60)

P = 48/100 = 40%

no , P cant be calculated with out calculating w

(Please read my previous post carefully)



P - is overall project progress.



Each activity has its contribution to the overall project progress. So each activity should be weighted .



"and there is no discrimination between tasks for which are more important than others" - This discrimination is achieved by giving weighting to the activity.



I cant explain beyond this ... These are international practices .. I have decent knowledge on this since I work in many green -field projects !



Cheers!



Sreejith

so...P can be found directly from the Hours without ever needing to calculate w:



P = Σ(p x w)

= (Σ(p x Estimated Task Hours))/(Total Project Hours)



But what use is P?



At a point in the project where P is expected to be say 50%, but is actually at say 45%, what does that tell us about "progress", really, since the 45% is just from a mixture of Tasks which are each in different states of progress, and there is no discrimination between tasks for which are more important than others?

Hi Trevoy,

Very interesting,

I will try to explain you the concept.

Manhours estimated for an activity an never ever used to measure the physical progress. If anyone is doing that, he is committing a big blunder.



Manhours estimated for an activity is used to give ’Weighting’ for the activity (Activity weighted based on effort)

Physial progress is to be measured by :

--------------------------------------

Physical progress , p = Qty installed / Total Qty

Weightage for the activity, w = Estimated Mhrs for the activity / Total Mhrs for the project

Σw = 100%



Weighted Progress ,k = p X w

Overall Project Progress P= Σ (p X w)

--------------------------------------



Hope this explains your query !



(If 100 hrs are estimated for a project and if the contractor ’dance’ for 100 hrs with out doing any useful work , and if the progress measurement is based on Hrs expended / Total estimated hrs , then once the ’dance’ is over contractor can invoice full amount, even though no changes happened physically !)



Cheers!

I find the word "progress" in this context to be ambiguous, perhaps misleading, and in any case un-informative.



So if "% progress" is the same thing as "% Work" why not just call it "% Work", which involves tangible, measurable quantities?



So if a certain Task is planned to involve 40 Hours of Work, and when finished does in fact rack up Actual Work = 40 Hours, and say the project is planned to involve 4000 Hours of Work, then % Work Complete = 40Hours/4000 Hours = 0.01, or 1%, correct?



How do you know, or why should anyone assume, that racking up Hours is the same thing as "progress"? Suppose a Task was to lay 5000 bricks in 5 Days of Duration and 40 Hours of Work, but after 2 days of Actual Duration and 16 Hours of Actual Work, there is only 1000 bricks instead of the expected 2000 bricks laid.

% Complete (Duration) = 2/5, or 40%,

% Work Complete = 16/40, or 40%,

% bricks = 1000/5000, or 20%



Surely the number of bricks laid, ie how much of the Task has been achieved, is a far better indicator of progress than how many Hours of Work or how many Days of Duration were required to achieve it?



Suppose the Task in the 4000 Hour project was planned to take 40 Hours of Work but actually took 80 Hours.

Is the "% Progress" (or % Work) still equal to 1%, or is it now 80 Hours/4000 Hours = 0.02, or 2%, or is it 80 Hours/4040 Hours (since the total Work is now the Actual (80)+ Remaining (ie Remaining is still 4000 - 40 = 3960, so 80+3960 = 4040)?

No Mr.Trevor,

It is just % of work completed.

Assume the total duration of refinery construction is 2 years or 24 months.

Initial mobilization and setup will take 2-3 months which turn out low progress per month/week.

Last 4-6 months for final commissioning also will be bit slow.

So lets assume the major construction/installation takes place in 14 months.

Assume we make 4% progress in first 3 months and 6% progress in the last 6 months.

This leave us with 90% progress to be achieved in 14 months

(This portion of the curve will generally be a linear function)

So, per month progress will be 90%/14 ie. 6.42% ..or per week 1.6 % - 2%.



Again this is project specific. The best way to find out monthly progress is:

1) Finalise the project schedule

2) Allocate weighting for activities

3) Generate planned S-Curve

4) Select x axis scale to months



Hope this info helps.



Cheers



Sreejith Nair

http://pmkarma.blogspot.com/

Thank you for your reply but does not answer my question.

Does this % "progress" have a numerator and a denominator, eg 50 apples/100 apples = 50% of apples?

% of what?

for factor of safety, consider it per month, just work on the delays and claims later

1-2% per week : poor

3-6 % progress per week is decent

6-7% Excellent

8% + :Check your progress tracker , you might have entered 1000 in place of 100 at some place ;)



The above figures are for construction..

During the lower & upper part of s-curve weekly progress will be 1-2%



Cheers!



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Sreejith K Nair

http://pmkarma.blogspot.com/









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