Method of disposing a tubular sleeve on a supporting element and apparatus to put said method into practice

A method of disposing a tubular covering sleeve for electric-cable joints on a supporting element, the method comprising:

• arranging the tubular covering sleeve in a rest and not yet expanded condition;
• causing radial expansion of the tubular covering sleeve starting from axially opposite end portions of the tubular covering sleeve;
• and
• arranging the tubular covering sleeve in a radially expanded condition on the supporting element;
• wherein radial expansion of the tubular covering sleeve is carried out gradually, starting from the end portions of the tubular covering sleeve toward an axially intermediate portion of the tubular covering sleeve,
• wherein causing radial expansion of the tubular covering sleeve comprises:
• arranging a pair of expanders, each at a respective end of the tubular covering sleeve and at a substantially coaxial position relative to the tubular covering sleeve;
• and
• introducing the expanders into the respective ends of the tubular covering sleeve;
• wherein introducing the expanders into the respective ends of the tubular covering sleeve comprises:
• abutting distal ends of the expanders against each other at the axially intermediate portion of the tubular covering sleeve;
• wherein each of the expanders comprises:
• a radially external tubular body;
• and
• at least one radially internal body;
• and
• wherein abutting distal ends of the expanders comprises:
• first abutting the radially internal bodies;
• and
• subsequently abutting the radially external tubular bodies.