Sunday, February 13, 2011

Why Microsoft Project should not be used as a Project Monitoring Tool

At first glance, Microsoft Project appears as a very user friendly tool for project scheduling and monitoring. Infact most of the L2 schedules, I have seen seem to have been done in Microsoft Project.

After using Microsoft Project on my last 4 projects ( average project value around  Rs 30 crores), there seem to many major flaws in Microsoft Project software, namely

1. Percentage Complete for any Activity is defined as Actual Time Spent on Activity divided by the Original Duration of the Activity. This to me seems fundamentally flawed. If i had an activity whose Original Duration was 10 days, and i spent 8 days on the activity, then Microsoft Project will show that activity as 80% complete while in reality it maybe only 20% complete due to slow progress.
This is a fundamental limitation of the software and i have discussed this with many of the scheduling experts and no one seems to have a work around solution for this.

2. Microsoft Project gives crazy results when an activity is started out of sequence. For instance after completing the structure of a multi-story building I had planned in MSP to do the brickwork first on the ground floor and then on the first floor. Now due to some issues, in reality i started my brickwork on the first floor and then i would do the brickwork on the ground floor. When we update this in MSP, it still keeps showing the ground floor brickwork activity in the past and does not move the task as something we have to do in the future. As a result the entire shedule becomes distorted and unreliable.

Over the last year, i have also been using Primavera in parallel with Microsoft Project and i am very happy with Primavera's scheduling capablites. It does not seem to have any scheduling flaws and seems to be giving correct results.

Thursday, February 10, 2011

Type of Work at Construction Site

As a Site-in-charge, most of my time is spent upon:

1. Planning - involves studying of drawings and determing the resources required to complete the work
2. Overseeing actual construction work happening at site
3. Keeping track of material in the site store
4. Correspondence with client and Head Office
5. Making reports regarding site progress and making RA bills
6. Keeping the sub-contractor focussed on the job at hand

Wednesday, February 9, 2011

Ash Handling System in a Thermal Power Plant

Coal is burnt in the furnace to heat the boiler to produce steam. Burnt coal is called ash. Some part of the ash falls to the ground and is called bottom ash and the ligher ash particles fly in the air and are called fly ash.
There are different systems for dealing with bottom ash and fly ash.

Bottom Ash: The bottom ash falls through the furnace grating and is collected in a hopper. Its then grinded and crushed to produce find powder ash. The powder ash is then mixed with water to produce ash slurry.
The ash slurry is then pumped to an open pond called the ash dyke.

Fly Ash: The flue gas exits the furnace and is finally disposed off through the chimney. Before the chimney a device called the Electrostatic Precipator is present which is electrically charged. The fly ash sticks to the screens of the electrostatic precipitator while the rest of the flue gas escapes through the chimney.
The stuck ash is then scrapped off the screen using a automated scrapper mechanism and collected in a hopper where it's conveyed to a silo either using air or mechanical conveyor system. The fly ash is stored because it can be used in the manufacture of cement or fly ash bricks. Hence its stored in silos and sold to cement plants and not disposed off like bottom ash