Electrification of paper-making machines

The ever increasing speeds of paper making machines has made necessary the replacement of the inadequate mechanical drive with electrical sectional drive, and the perfection acquired in modern electrical sectional paper machine drive has made possible unlimited paper speed in so far as the drive and control is concerned. Not only is electrical sectional drive necessary for high speed machines but it is highly economical for even the slowest speed machines on account of the saving in power over mechanical drive, the great saving in maintenance, and the greater precision with which the section speeds can be maintained thereby greatly reducing the number of paper breaks and increasing production. This paper outlines the several trends of development in an historical sketch of progress in the art up to the present time, devoting special attention to a unique system of direct current drive in which the section driving motors through a differential electrical field control means, cause the several section driving motors to operate in synchronous relation at any desired relative speed values, which speed relations are at the same time adjustable at the will of the operator.