A GIANT ELECTRIC MOTOR.

Wanganui Chronicle, Volume LXVI, Issue 7564, 7 May 1919, Page 7

A GIANT ELECTRIC MOTOR.

Tho driving of a rolling mill is one of the heaviest problems which an engineer has to solve. In i-tse.'f the machinery is massive; and the work "of rolling hugo billets of steel stage by stage down to rails or beams involves spasms of enormous energy at frequent intervals. Moreover the mills are usually kept running night and day, to that the driving plant must be reliable an well as powerful. Fora long time it was doubted whether electric powar could satisfactorily take the place of the magnificent steam engines which British engineers had evolved for rolling null w6rk, but experience proved that it could be made ut least equally reliable whii» it was more economical in power and in space. Special types of motor had to be designed for rapid reversing and special accessories to supply the bic reserve of power required when the billets iust enter the rolls. One of the lates* and largest equipments of this kind in Great Britain is driven by an electric motor of no less than 20,000 liorse power There is no other form of power which enn meet every demand from atiny dentist's drill up to tho colossal rolling mil.