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How are great teachers different from excellent teachers? Great teachers explain with wonderful examples.
How are great teachers different from excellent teachers? Great teachers explain with wonderful examples.

Kabooters on the cantilever

I have an old friend who is a civil engineer with a brilliant sense of humor. He told me this story about how an excellent example can cut across cultural, bureaucratic, hierarchical and personal barriers to convince something to someone. First I will try to give you a little feel of the background of how large projects get built, so that you can understand the simple but powerful essence of the story.

Under-construction power projects in India have a typical look. If you work in or with the power industry you may have seen this many times from a distance. But let me take you there and take a closer shot. There is a mass of land (few hundred acres) surrounded by an incomplete boundary wall. A potholed road tees off from the main road leading upto a security gate. Past that gate, somewhere in the middle of the land mass there is half built chimney. Below the chimney, there is a heavy steel structural built-up called the boiler and beside the boiler there is a somewhat longer covered structure of lower height called the turbine house. This is called the "main plant". Around the "main plant" you can also see scattered construction of some isolated buildings providing other services to the plant called the "offsite" areas sometimes called the BOP, or balance of plant. The main plant is the nerve center of the project. Here, several contractors work together on different packages of the plant - Boiler, turbine and generator suppliers, pipe erectors, cable pullers, electrical contractors, C&I contractors and many others.

Gadarwara STPP under const

One of the most challenging aspect of construction of large projects is played out when several contractors from different industry sectors work together in the same space at the same time - many times trying to complete conflicting tasks. Sometimes the conflicts are purely physical, some other times conflicts are logical or sequential. Each of them tries to complete a part of the "whole project" without a great deal of understanding of what or how another person is doing his part. But the problem gets compounded when these people belong to different discipline of engineering, work for different companies, have vastly different work experience, and want to do entirely different types of work in the same room at the same time. That is why large projects are "interfacing nightmares". Talking of "interfacing", it is not so easy (read - actually painful) to interface piping, civil, structural, during engineering phase of a project. But interfacing a civil engineer with a piping engineer is quite a challenge, because their language, their dictionary, their sense of accuracy and their factor of safety are all different. For example, if a piping engineer is thinking of mismatch errors in millimeters, the civil engineer may not care for such errors if he is within a couple of centimeters.

Consider there is a cantilever welded to a main boiler column at a height of 15/20 meters from the ground. The purpose of this cantilever is to support a couple of 10/12 inch diameter pipes that will carry hot water from the boiler. There is enough space available on the length of the cantilever after the pipes have been placed and supported over the cantilever. The site civil engineer of another contractor wants to take support of this cantilever and take a small compressed air pipe to the to the next column of the boiler. The cantilever has been designed by the boiler manufacturer and the piping engineer has ownership of the cantilever. The civil engineer is from a different company and wants to convince the piping engineer to allow him to use the cantilever. He is desperate to complete this small task because that is the only thing pending in his task list to complete his work.

Now the fun begins.
The piping engineer says his erection and design drawing shows two water pipes on the cantilever and he will not support any additional items on the cantilever. The civil engineer says, "Why not?. There is enough space and the one inch diameter compressed air line can be very well supported within the margin of safe design". Looking at the compressed air line, any seasoned engineer will not have the slightest worry that the cantilever will get overloaded with the small additional pipe. But the piping engineer in not convinced, and the job is still not done.

The problem gets escalated and reaches a review meeting. When this point comes up, my friend justifies why supporting the pipe on this cantilever is the best solution. The piping engineer says he will have to get clearance from their engineering team if we have to do that. The impasse creates a few moments of silence. People look at each other. Is that necessary ? How long will it take? My friend looks at the piping engineer and asks, "Are you saying that the design of the cantilever is so delicate that it will bend tomorrow if a couple of pigeons come and sit on it?" The sheer brilliance of the example and the graphic image that the example brings in everybody's mind is powerful and vivid. Everybody is smiling. The piping engineer is also smiling but still holding on to his side lamely. It has convinced everybody that supporting the small one inch diameter pipe will not put any excessive weight on the cantilever whatsoever. The boss is convinced beyond all doubts and says, "Let your engineering find out how many pigeons can sit safely on this cantilever but in the meanwhile, let us use the cantilever to support the pipe and finish your work".


Everybody including the piping engineer had a hearty laugh.

Last modified onTuesday, 09 August 2016 19:12
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