A pipe cleaning machine is provided in which rotary wire brushes remove rust and/or dirt from the exterior of pipes of various diameters. Feeding means is provided for driving the pipe lengthwise while rotating it. Provision is made of optionally usable means for reversing the direction of travel of the pipe if it is seen to require further cleaning after one or more passes. It is a feature that through a simple adjustment the number of turns per foot of pipe advancement may be varied, a feature of importance in relation to different diameters of pipe and to the observed need for increasing or diminishing the intensity of total treatment. The capacity for reversal of travel is important for continuing treatment of the pipe until the observed degree of cleanliness is acceptable. Reversal of travel can also simplify the handling of the pipe for a single attendant because the cleaned pipe can be withdrawn at the same end of the machine from which the rusted or dirty pipe is fed in.