To simplify a device and to improve production efficiency.
A cutting tool holder 32 is attachably, detachably and replaceably disposed on a tool rest 30. The cutting tool holder 32 is positioned and fixed to the tool rest 30 via a bolt 34. A first mounting part 40 with an attachably, detachably and replaceably stored outside face chip 38 for performing beveling chamfering for an outer end part of a steel tube 16 is formed at the front part. The outside face chip 38 is positioned and fixed to the first mounting part 40 via a fixing bolt. A second mounting part 48 with an attachably, detachably and replaceably stored mounting tool 46 provided with an inside face chip 44 for performing the beveling chamfering for an inner end part of the steel tube 16 is formed at the front part of the cutting tool holder 32. The mounting tool 46 is positioned and fixed to the second mounting part 48 via a fixing bolt 50.
KATO KENJI