Envelope or other elongate element processing

A process for performing a plurality of operations on an elongate element, in particular an envelope (60) in a folder-inserter machine, which operations, such as flapping (44, 47), inserting, moistening and sealing, are carried out at spaced-apart locations. The process enables various different lengths of envelope to be employed, without the need to adjust any of the mechanisms. This is achieved by feeding an envelope into the inserter unflapped and with its crease line trailing. A datum position for the crease line is determined following sensing (96), and all the distances the envelope needs to be moved for the various operations, which may in practice be closely associated with that crease line, measured from that datum position. Irrespective of the lengths of the envelopes processed, the drive means (43) moving them from one particular operation location to the next then needs to be operated for the same time.