Patent ID: 6216326
Filing Date: 2001-04-17
Classification: B23P,B25B,Y10T

Abstract:
A tube pulling apparatus comprising:a source of pressurized hydraulic fluid;a body;a hydraulic fluid feeder line extending into said body to pass hydraulic fluid under pressure therethrough from said source of pressurized hydraulic fluid;a pull shaft having a hollow portion slidably mounted over said hydraulic fluid feeder line for receiving hydraulic fluid therein from said source of pressurized hydraulic fluid;an inner piston connected to said pull shaft and positioned to move said pull shaft responsive to hydraulic fluid pressure from said source of pressurized hydraulic fluid;a puller tube slidably mounted over said pull shaft;an outer piston connected to said puller tube and positioned to move said puller tube responsive hydraulic fluid pressure from said source of pressurized hydraulic fluid;a spool valve formed between said pull shaft and said puller tube for activating said outer piston upon a predetermined movement of said pull shaft inside said puller tube; andtube gripping means connected to said pull shaft and puller tube for gripping and pulling a tube therewith by sliding said pull shaft to activate said gripping means and sliding said puller tube to pull said gripped tube.