Abstract: Cold lining technology of small diameter stainless steel liner for pressure vessels is widely used on offshore platforms, so it is necessary to study it systematically. Firstly, the simplified mechanical model of cold lined composite pipe is established, and the calculation formula of the minimum interference under internal pressure is obtained according to the theory of elasticity. Then, aiming at the typical small-diameter nozzle, five different interference models are established by using the finite element analysis software ANSYS, and the distribution laws of contact pressure and stress intensity of the assembly joint surface of cold lined composite pipe under cold lining state and internal pressure state are obtained. Finally, in order to study the influence of internal pressure on the stress of cold lined composite pipe, four groups of different internal pressure are loaded according to the typical model, and the distribution law of stress intensity on the assembly joint surface of cold lined composite pipe under internal pressure is obtained.

Key words: cold lined composite pipe, interference fit, mechanics study, stress distribution