System for maintenance of the preload of joints of flanged type parts and associated procedure for mounting a joint.

摘要

A system for preload maintenance of joints of flanged type parts with a bolt (P) and two pieces (B1, B2) is provided, consisting of nut means (10) with internal threading (100) along a threaded shaft (e) and washer means (11) to insert into the bolt. The nut means (10) have a lower beveled surface (101) forming an acute angle (Xo) with the perpendicular to its threading axis (e) and a guiding portion (102), coaxial to said threading axis (e ) and extending over a length (L1) from the inner edge of the bevelled portion; the washer means (11) having a flared mouth (110) with the same inclination as the bevel (101) and a radial extension equal to or greater than the bevel, the mouth extends through a cylindrical guide hole (111) that is extends the length (L1) of the neck portion (102) of the nut by a length (L2) of less than or equal. In the closed state of the system (1), the bevel lies supported by the mouth of the washer and the neck portion (102) inserted in the cylindrical guide hole (111), distributing the preload stress in its normal components and axial.