Retractable finning tool and method of use

摘要

An improved tool (10) and method for enhancing the surface of a heat transfer tube (62) are provided. The tool (10), which can be easily added to existing manufacturing equipment, includes cutting bits (28) that may be retracted with a housing (12). The cutting bits (28) include a cutting edge (32) to cut through the surface of a tube (62) and a lifting edge (34) to lift the surface of the tube (62) to form protrusions. A method for enhancing the inner surface of the tube includes mounting a tool (10) on a shaft (14), positioning the tool (10) in the tube (62) and causing relative rotation and axial movement between the tube (62) and the tool (10) to cut at least partially through at least one ridge formed along the surface of the tube to form ridge layers and lift the ridge layers to form protrusions.