Chemical cutter and method for high temperature tubular goods

Abstract

Chemical cutting processes and tools for use in a well bore useful in the cutting of high strength and corrosion-resistant downhole tubular goods. The cutting tool has an elongated tool body comprising a chemical section and a cutting section having a plurality of cutting ports therein. After lowering the cutting tool to the desired location within the well, the cutting agent is discharged from the chemical section into contact with an ignitor material formed of a permeable mixture of metallic ignitor component and a promoter component which can be a metallic component or a grease component or both. The promoter component is formed of a material which is exothermically reactive with the cutting agent at a first temperature and the ignitor component is exothermically reactive at a higher temperature. The ignitor component may be formed of a predominately or entirely non-ferrous corrosion-resistant metal alloy. The pre-ignited chemical cutting agent is dispensed from the cutting tool in a plurality of jet streams emanating from the cutting ports in the cutting section of the tool and into contact with the inner surface of the tubular member to effect a cut therein.