Page 8 - Artificial Lift Methods
P. 8

ARTIFICIAL LIFT METHODS



        Petroleum Extension-The University of Texas at Austin





                                                        Units of Measurement




                                                                                           ▼
                                                                                           ▼
                                                                                           ▼


                                                   hroughout the world, two systems of measurement dominate:
                                               Tthe English system and the metric system. Today, the United
                                               States is one of only a few countries that employ the English system.
                                                   The English system uses the pound as the unit of weight, the
                                               foot as the unit of length, and the gallon as the unit of capacity. In the
                                               English system, for example, 1 foot equals 12 inches, 1 yard equals 36
                                               inches, and 1 mile equals 5,280 feet or 1,760 yards.
                                                   The metric system uses the gram as the unit of weight, the metre
                                               as the unit of length, and the litre as the unit of capacity. In the metric
                                               system, 1 metre equals 10 decimetres, 100 centimetres, or 1,000 mil-
                                               limetres. A kilometre equals 1,000 metres. The metric system, unlike
                                               the English system, uses a base of 10; thus, it is easy to convert from
                                               one unit to another. To convert from one unit to another in the English
                                               system, you must memorize or look up the values.
                                                   In the late 1970s, the Eleventh General Conference on Weights
                                               and Measures described and adopted the Systeme International (SI)
                                               d’Unites. Conference participants based the SI system on the metric
                                               system and designed it as an international standard of measurement.
                                                   The Well Servicing and Workover Series gives both English
                                               and SI units. And because the SI system employs the British spelling
                                               of many of the terms, the book follows those spelling rules as well.
                                               The unit of length, for example, is metre, not meter. (Note, however,
                                               that the unit of weight is gram, not gramme.)
                                                   To aid U.S. readers in making and understanding the conversion
                                               system, we include the table on the next page.














                   xvi
   3   4   5   6   7   8   9   10   11   12   13