Sunday, July 8, 2012

Confusing units of measurement and standards

When we were young and under the influence of British colonial rule, we were taught to use all feet, inches, pounds, Fahrenheit degrees and miles etc as our units of measurement. Upon the time when SI units were introduced into our science textbooks for our "O Level Cambridge Examination", we were told to discard all those imperial units and get on with cm, Kg, Centigrade and kilometers etc. Initially I really had a hard time to interpret them when I used to tell my friends that I am 5 feet 6 inches and weigh 150 lbs and now I have to say them differently as 168cm and 68Kg. The Americans are still using the old imperial units and sometimes I could not figure out how cold or how hot is the weather forecast in Fahrenheit while we are so used to the Malaysian tropical mid day temperature of 32 degrees Centigrade and the freezing coldness of minus 4 degrees Centigrade in Qingdao of Shandong China as our frame of references in our mind.

Here comes again another complication about the sizes of the factories that I used to work for. The current plant that I am working is with an area of 8.3 hectares and base on 1 hectare equals to 2.47 acres, and the total land area is roughly about 20.5 acres. 1 acre is 43,560 square feet and therefore to answer a Singaporean who asked me on how many square feet, the Lion Plate Mills factory area is roughly 900,000 square feet. So by the same calculation, the Silverstone tires plant in China is double the size of this, it means to say the land size is now 40 acres or 1.8 million square feet.

We used to have an exchange rate of 1 USD = 2.5-3.0 Malaysian Ringgit or RM and therefore it is customary for us to quote our sales revenue in millions of RM per month. When you are transferred overseas, one has to mention them in US dollars, for example, the Silverstone China plant with a headcount of 580 people was roughly USD 8 millions per month, that of Mexico plant with 800 employees was in the region of USD3-4 millions per month whereas Lion Plate Mills sales turnover with just 180 workers is almost the same as that of the Mexican plant. Steel plate is a bulky item and that accounts for the high sales revenue though with lower number of headcount.

Very often someone will ask me what kind of steel plates that we are producing? We are producing plates complying to the various standards of BS4360 50B or EN10025-2 S355JR, BS436043A or EN10025-2 S275JR, JIS G3101 SS400 and ASTM A36 . This sounds confusing enough? They are just different standards used by the British, Europeans, Japanese and the Americans. We normally omit the BS, EN, JIS and ASTM portions and simply quote the standards as 50B, 43A, S355JR, S275JR, SS400 and A36! Once we have different countries setting their own standards, the confusion starts to creep in!

Our finished products are considered as low carbon steel plates with carbon content ranging from 0.12-0.17. Basically these plates are with Carbon Equivalent or CE between 0.24-0.34. The CE comes into play because some of the other minerals such as Manganese tend to have certain effect on the steel mechanical properties. The CE is defined simply as C + Mn/6. Since we are producing these steel plates mainly as structural steels and therefore the weldability of the steels is important. Generally speaking, the weldability of steel plates with CE of 0.35 and below is good while anything exceeding 0.5 would be poor.

I do not intend to write this as something too technical, just to quote here a few examples of how our minds are confused with all these conversion of units and standards!


2 comments:

  1. Wahhhh.... so technical kinda post.

    I read without understanding half of what I read. Hehehe....

    But I just had to leave a comment so that this ole friend of mine knows that I's still following him!

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    1. Ahan, thank you for continue to follow my blog even though I hardly write. Spend more time on facebook nowadays!

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