The present invention provides a casing system for integration of modular internal intervention equipment in tubular lines, wherein the equipment comprises a plurality of modules (2), the casing system comprising a sleeve (1) encasing, in an integral manner, at least one module (2) of the plurality of modules (2) and at least one portion of at least one component upstream (3, 2) or downstream (2, 2a) of said at least one module (2). The integration casing system of the present invention guarantees the mechanical integration of all the modular internal intervention equipment, rendering viable the operation thereof inside tubular lines in a safer, more efficient and more advantageous manner.