The retained mandrel for the production of large-sized seamless steel pipe is used in sectional structure. Its working section is exposed to complex and huge surface pressure as well as thermal cold-hot fatigue, whereas its connection part has to withstand mechanical forces during the pressing process.
The working part of the retained mandrel produced by CBR adopts H13 hot-work die steel. The many production processes, that include smelting, forging, rough machining, heat treatment, semi-finished & finished machining, chrome plating and phosphate treatment, ensures the following characteristics:
CBR is upgrading the mandrel material and its manufacturing technology in close collaboration with Baosteel Research Institute.
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