An apparatus (24) for inserting an endless, flexible clothing (15) in or removing such a clothing from an industrial machine in which the clothing is arranged to run in an endless loop, comprising first and second units (25, 26) between which the clothing is to be fed in an advancement direction (F) essentially transversal to the run direction of the clothing in the machine. According to the invention the apparatus comprises an upstream zone (A), an intermediate zone (B) and a downstream zone (C) along the advancement direction of the clothing; and also a member (29) for bringing the units to interact in the first zone and the third zone, alternately, such that the clothing is locked between the units in the first zone and the third zone, alternately, allowing the feeding of the clothing into the upstream zone when the clothing is locked between the units in the downstream zone such that the clothing is accumulated in the intermediate zone, and allowing the feeding of the clothing accumulated in the intermediate zone into the downstream zone when the clothing is locked between the units in the first zone such that the clothing is fed out of the apparatus through the downstream zone (C).