Non-lubricated compressor with abradable sealing element and related method for assembling it

A method for assembling a non-lubricated compressor (10) comprising:

• a stator (12) with a housing (18) comprising a rotor cavity (20) delimited by a bottom wall (22), a top wall (24), and a lateral wall (26) connecting said bottom wall (22) and said top wall (24),
• a rotor element (14) arranged for rotation about an axis (z) within the rotor cavity (20) for compressing a gas therein,
• a sealing element (16) arranged within the rotor cavity (20),
• the compressor (10) being characterized in that
• the sealing element (16) is made of an abradable carbon material, and in that
• the sealing element (16) comprises a wall portion (34) arranged on an inner surface of the lateral wall (26) of the rotor cavity (20),
• the method comprising the steps of:
• a) manufacturing the semi-finished sealing element (16) by machining a block of abradable carbon material so that an outer shape of said block copies an inner shape of said rotor cavity (20), and so that the block has an open, inner cavity delimited by a bottom wall and by a lateral wall that has a constant thickness;
• b) heating the housing (18) of the stator (12) to a temperature of at least 350° C.;
• c) fitting the semi-finished sealing element (16) inside the rotor cavity (20) of the housing (18) as long as the housing (18) is at a temperature of at least 350° C.;
• d) mounting the rotor element (14) inside the inner cavity of the semi-finished sealing element (16);
• e) running the rotor element (14) so that the inner cavity of the semi-finished sealing element (16) is further machined by the rotor element (14).