The paper offers a calculation scheme of delaminating occurring in complex metal composite pressure vessels. The calculation is carried out in LS-DYNA software in dynamic formulation using 3D-finite-element discretization of the SHELL- and SOLID-types. Technological deviations have been introduced into the computational scheme, in which a unilateral constraint on the surface contact area is also taken into consideration. The analysis of delaminating is carried out by example of a vessel with a carbon-plastic shell and an aluminium liner in the process of thermal treatment of the vessel. It is shown that at certain heating temperatures of the vessel, liner delamination from the rigid composite shell may occure. Delamination is due to local buckling of the metal thin-walled liner occurring in the areas of technological deviations. Delamination has the form of folds (internal deflection), which in the form are subdivided into annular and radial folds on the bottoms and into the contour (turning into longitudinal) folds on the cylindrical part of the liner. Temporal process of wrinkling on the liner surface during heat treatment of the vessel is shown (video).