File:Electric locomotive haulage in and about mines (1913) (14757932212).jpg

Identifier: electriclocomoti00newt (find matches)
Title: Electric locomotive haulage in and about mines
Year: 1913 (1910s)
Authors: Newton, Leonard Victor
Subjects: Electric locomotives Mine railroad cars Electric railroads Theses
Publisher:
Contributing Library: University of Illinois Urbana-Champaign
Digitizing Sponsor: University of Illinois Urbana-Champaign

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
omotive, for the motor becomes warmwhen the load is applied, and soon it is warmer than the surround-ing air, and the heavier the load the faster is the heating. Inestablishing some satisfactory rating for electric motors it isnecessary to take into consideration this heating effect, and con-sequently a limiting temperature must be determined up to whichthe motor may operate without injuring the windings. Most electriclocomotive manufacturers have rated their locomotives on a 75 de-gree Centigrade rise from a temperature of 25 degrees Centigradein one hour; that is,a locomotive when operating under normal con-ditions for one hour will have a rise of 75 degrees C. in the mo-tor. In the accompanying curves, Plate 44* the figures are takenfrom tests of the Baldwin Westinghouse Co. The locomotive was a36,000 pound standard mine locomotive. Curve A is a time-draw-bar pull curve and shows the length of time the locomotive willgive different values of draw-bar pull with a temperature rise of
Text Appearing After Image:
U. OF I. S S. FORM t 31 seventy-five degrees Centigrade when starting cold. Time curve Bshows the length of time it is safe to use the locomotive at thevarious values of draw-bar pull without injury to the motors,butstarting with the motor temperature at seventy-five degrees Centi-grade instead of starting cold. The speed curve shows the speed of the locomotive at variousvalues of draw-bar pull. The nominal rating of the standard eight-een ton locomotive is 7200 pounds draw-bar pull and by referringto the time curve A we find that the time curve croeses thehorizontal line corresponding to sixty minutes at a point vertical-ly over a current value of 570 amperes. Then following up thevertical line corresponding to this current we find it crosses thedraw-bar pull curve at a point on the horizontal line correspondingto 7000 pounds. The one hour rating of this locomotive is thenfound to be 7000 pounds draw-bar pull,and by similar methods itis seen that this locomotive will give 9000 pounds

Note About Images