The measurement of pressure distribution in industrial rolling processes has hitherto been carried out only on roller systems of the fixed gap type. The apparatus described here extends the measurement to processes in which there is no fixed gap between the rollers, and also to appreciably lower loads than any previously studied. A radial pressure pin is mounted in one of the rollers and transmits the load on its outer end to a pressure-sensitive device situated within the roller. Provision has been made for the investigation by actual pressure-distribution measurement of the effect on recorded pressure of the height of the pressure pin relative to the roller surface and of depression of the pin under load. Pin depression has been found to cause erroneous pressure recording, and a method of correction has been developed.