Hot extrusion die and hot extrusion integral forming method for special-shaped square pipe

US12090536B2 · kind B2 · utility

Assignees

• CENTRAL IRON AND STEEL RESEARCH INSTITUTE · CN
• HANDAN XINXING SPECIAL STEEL PIPES CO., LTD. · CN

Inventors

• Zhenbao Liu · Beijing, CN
• Xiaohui Wang · Pittsford, US
• Jianxiong Liang · Beijing, CN
• Yongqing Sun · Beijing, CN
• Changjun Wang · Beijing, CN
• Zhiyong Yang · Beijing, CN
• Yuguang Gao · Ithaca, US
• Jie Gao · Beijing, CN
• Fuqiang Liu · State College, US
• Ailiang Zhang · Beijing, CN

Key dates

• Filing date: Apr 15, 2021
• Grant date: Sep 17, 2024
• Expiry date: Apr 15, 2041

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B21C29/003
• WIPO field: Machine tools
• WIPO sector: Mechanical engineering

Abstract

A hot extrusion die for a special-shaped square pipe includes a die cavity sleeve with a special-shaped cavity. A hot extrusion mandrel is arranged in the die cavity sleeve. An area between the die cavity sleeve and the hot extrusion mandrel forms a die cavity hole. A first extrusion diversion hole and a second extrusion diversion hole are arranged below the die cavity hole. An integral centroid of the die cavity hole is located at a circle center of a radial cross section of the die cavity sleeve. Further disclosed is a hot extrusion integral forming method for a special-shaped square pipe, including: heating and expanding a blank material; heating the blank material again after expanding; performing hot extrusion on the blank material; and cooling the formed special-shaped square pipe in air to a room temperature, and inspecting surface quality and mechanical properties of the special-shaped square pipe.