The conventional method for attaching hardware, such as support brackets and rings for alternate path shunt tubes and bladed centralizers, to oilfield sand screen tubulars and other downhole equipment involves welding such components directly to the production tubular. Welding creates residual stresses in the tubular that can eventually lead to stress or corrosion cracking, surface cracks, and other defects that can ultimately result in the failure of the tubular. However, most welding procedures generally include a post-weld heat treatment designed to minimize the residual stresses and increase the strength of the tubular near the weld joint by re-homogenizing the crystalline structure of the tubular material. However, with increasingly sophisticated metallurgy, such as 25CR-125ksi material commonly used in downhole applications, regaining vital strength properties of the tubular is simply not possible through post-weld heat treatments. Consequently, in applications using modem metallurgy, welding directly to the production tubular will ultimately result in the tubular having reduced strength characteristics as a result of the residual stresses on the tubular.
Moreover, in order to comply with downhole drilling regulations, the tubular weld must also be thoroughly inspected in an effort to identify any weld defects that could eventually propagate into cracks and lead to tubular failure. This inspection is commonly undertaken via non-destructive weld examination methods, such as liquid penetrant inspection. Like many other non-destructive weld inspection methods, liquid penetrant inspection requires an in-depth system of quality control documents, traceability, and personnel training which are inherently time consuming and cost prohibitive for many applications.
There is a need, therefore, for a system and method of attaching downhole equipment hardware to production tubulars without welding such equipment thereto and thereby compromising the structural integrity of the tubular and requiring costly post-weld treatments or inspections.