Abstract: A slitting machine is disclosed which feeds corrugated pipe through the machine intermittently and between the periods of pipe feeding when the pipe is stationary a plurality of angularly spaced saw sets are moved radially inward toward the machine axis and the pipe to cut slots through the wall thereof, and then withdrawn whereupon the cycle repeats. The pipe is fed through the machine by endless transporters equal in number to the saw sets and uniformly disposed angularly with respect to each other, the saw sets and the axis. The transporters have projections which fit into the corrugations of the pipe for a driving connection therewith. A saw set is located angularly between each pair of transporters so that a pair of the latter are roughly opposite to a saw set for an even number of sets or directly opposite a transporter for an odd number of sets.