Abstract

Disclosed are differential temperature push bending method and device for tube with small bending radius, the device comprising: a push bending die, core, fillers and pushers, wherein the core and the fillers are both arranged in a bending chamber of the push bending die, an inlet and an outlet end of the push bending die are respectively provided with a front guiding sleeve and a rear guiding sleeve, the pusher in the front guiding sleeve abuts against a plurality of fillers, and the pusher in the rear guide sleeve abuts against the core. A heat rod is provided at an outer end of the bending chamber. The present disclosure adopts differential temperature type push bending, flow performance of the tube blank at the outer corner of the die can be improved, and the material can be timely fed to prevent excessive stretching and thinning of the outer material.

IPC Classes  ?

• B21D 7/16 - Auxiliary equipment, e.g. for heating or cooling of bends
• B21D 7/08 - Bending rods, profiles, or tubes by passing between rollers or through a curved die
• B21D 9/15 - Bending tubes using mandrels or the like using filling material of indefinite shape, e.g. sand, plastic material
• B21D 9/18 - Auxiliary equipment, e.g. machines for filling tubes with sand for heating or cooling of bends
• B21D 37/16 - Heating or cooling
• B21D 9/12 - Bending tubes using mandrels or the like by pushing over a curved mandrelBending tubes using mandrels or the like by pushing through a curved die
• B21D 37/18 - Lubricating

Abstract

A method and a former for necking and thickening a tube end. The former includes a hydraulic cylinder, a pusher, a concave die, a filler block, a plurality of heating rods and a heating device. The hydraulic cylinder is connected to a disc provided with a guide sleeve. The pusher is provided on the hydraulic cylinder and passes through the guide sleeve. The concave die is provided at a side of the pusher and includes a mold cavity and a plurality of heating holes. The filler block is provided in the mold cavity. The heating rods are provided in the heating holes connected to the heating device. The filler block includes a tapered portion provided at one end of the filler block and a diameter-reduced portion. The tapered portion is threadedly connected to the diameter-reduced portion. An ejector pin is provided at one end of the diameter-reduced portion.

IPC Classes  ?

• B21C 1/26 - Push-bench drawing
• B21D 37/16 - Heating or cooling
• B21D 37/10 - Die setsPillar guides
• B21C 37/16 - Making tubes with varying diameter in longitudinal direction
• B21K 21/12 - Shaping end portions of hollow articles
• B21J 1/06 - Heating or cooling methods or arrangements specially adapted for performing forging or pressing operations