Confusion of Conversions

Confusion of Conversions

Our generation started schooling when Imperial measurement system was followed in India.

One Rupee was 16 aanas. Each aana was 6 paise and each Paisa was 2 pai. Alongwith this we learnt Pound, Shillings and penny system of currency. Our initial arithmetic exercises required us to consider the intricacies of these. Many Proverbs have their roots in this currency system. Truth was 16 aana such. Aamdani atthanni, kharcha rupiah was another popular proverb. People were belittled by calling them chavanni chhap.

The metric system was introduced and during transition period Aanna was still used. Old Paisa was replaced by new Paisa. Pai lost it's existence. Lowest denomination coin was 1 Naya Paisa. 4 Aanna became 25 Naye paise which earlier was 24 Paisa. All our earlier learning lost it's value.

Weight was measured in pounds which was called seer or Sher in local language. Below pound we had Tola, Masa, ounce etc. Above pound was Indian measurement of Man equivalent to tonne. But in imperial system we had short and long tonnes confusing average students doing conversion.

All this was replaced by kilogram and we had exercises converting KGs to Pounds and vice versa.

Volume was measured by quart, pint and gallon. We still have a conical measure which is called Payali. Some items which basically should be weighed are still sold by Payali. Milk in many places though measured by volume was sold by seer.

Volume  measurement became litre. 

Temperature measurement was in Farenheit. It was replaced by Centigrade now called Celsius. After 60 years people are comfortable with body temperature in Farenheit. Thermometer shows both Celsius and Farenheit scales, but  98.6 is still the popular measurement. The charm in Newspaper headline announcing city temperature crossing 100 degrees Fahrenheit is lost now. Now temperature crossing 45 degrees Celsius doesn't have the same impact.

Linear measurement was in Inch, Foot, Yard, Furlong and Miles. Knot was additional measurement. In India we had another measurement of Kos. Kos is derived from Krosh as in Panchkroshi. Ask any cricket fan, he knows pitch length is 22 yards. Ask him in metres and he will not know. Milestone word is also derived from this measurement system. Mileage was the word for finding out efficiency of vehicle. For decades the measures of miles and furlongs could be seen on the roads. 

Area was measured by square-feet, square-yard and Acre. Below Acre we had Bigha or Guntha or Ground as measurement. Even today other than Government, people are comfortable with Acre as measurement. We have to remember 1 Hectare is equal to 2.5 Acres. Many items are sold by running feet with the standard width specified in feet. Masons, painters and others quote rate by square feet. Bricks also use Inch dimensions. 

Power was measured in Horsepower or Footpounds. In metric system it became Kilowatts. So remember conversion factor for power. Kg-m to Footpounds. Joules to BTU and so on. Even today people are comfortable with HP of pump than KW. Vehicles also specify their brake horsepower (BHP). 

Pressure was measured in Pounds per square inch (PSI) or Mercury column in inches. It became Kilogram per square milimiter. Again conversion exercises.

When we started our career, our battle with these conversions continued. The collaboration with American, Czech, Russian, German and other country companies made our job challenging. We had to find out values for British, American, German standards and their equivalent Indian measurement. Pipe threads were the most confusing. We had NPT, NPS, BSP, BSW in addition to metric threads. Arranging appropriate tools and maintaining the stock was a daunting task. Conversion of Thou (Thousandath of an Inch)  to Microns was also required.

While converting the drawings, dimensions were charged from inches to millimeter. Nearest rationalised material and tool sizes was used. During this adequate care was not taken, leading to assembly/ performance issues.

In India we use Third angle projection system for drawing. American companies use First  Angle projection system for drawing. Once we had problem during assembly. When I asked Engineering to show me CE drawing, the problem became clear. The draftsman had copied the drawing without bothering to correct projection.

When it came to piping and pressure parts, meeting the requirements of IBR, British standards and ASTM/ ASME by corelating the production problems was also one of the requirements. Nominal bore, OD/ ID, thickness and related issues with respect to welding, heat-treatment, radiography were required to be clearly understood. Corelating plant material standards with international standards and then using appropriately became an issue while executing export orders.

The problems in boiler were not exclusive, similar problems existed  in other products also.

Hope the new generation doesn't have to face similar problems.