Analysis of the mechanical properties of Bow-spring centralizer

Abstract

The bow spring centralizer is a crucial tool for enhancing casing centralization and cementing quality. In order to study the replacement of metal materials by thermoplastic composite materials with bow-spring centralizers, this paper completed the mechanical experiment of thermoplastic composite materials, studied the numerical simulation analysis of the working process of the bow centralizer of thermoplastic composite materials, and explored the influence law of the bow wall thickness, radius, chord length and limiting distance of the bow-spring centralizer on the mechanical properties. The results indicate that thermoplastic composite materials can replace metal materials; increasing the wall thickness of the bow can enhance the reset force and load-bearing capacity; as the bow radius and chord length increase, the reset force initially increases and then decreases, while the tensile and compressive stresses shows little variation; the limiting distance can effectively improve the reset force, but it may lead to an increase in local pressure stress of the bow-spring centralizers，the trends of the restoring force and stress changes are consistent with those expressed by the pseudo-rigid body analytical formula. For a 5.5-inch thermoplastic composite bow spring centralizer, the optimal structural parameters are: a wall thickness of 9 mm, a radius of 325 mm, a chord length of 255 mm, and the best limiting distance is 4 mm.