BORRHUVUD
申请公布号:SE8003905(L)
申请号:SE19800003905
申请日期:1980.05.27
申请公布日期:1981.11.28
发明人:WESTERMARK L
分类号:E21B7/28;E21B10/20;E21B10/28;(IPC1-7):E21D9/10;E21D3/00;E21B10/26;E21B10/34
主分类号:E21B7/28
摘要:A boring head for reaming a pre-drilled hole in raise boring or for similar earth cutting operations comprising a plurality of roller cutters (13-22). For purposes of extending the radius of the boring head (10) in operation or decreasing its dimensions during transport one or several extension elements (36, 37) are provided for detachable attachment to the boring head (10) by means of a wedge connection (42).