HEADER CUTTER Russian patent published in 2014 - IPC E21C27/24 

FIELD: process engineering.

SUBSTANCE: invention relates to continuous-operation headers. Header cutter comprises support element, extensible cutting head arranged at support element front end with central main part and at least one extensible drum part arranged at butting head end outside in axial direction from said cutting head main part. Extensible drum part has axial inner end abutting on cutting head main part. Axial outer end comprises inner end structure secured to cutting head main part and outer cylinder secured thereto. Inner cylinder secured to said inner end structure is located inside outer cylinder and aligned therewith. Extensible cylinder has inner circular expanded end with the part located between said inner and outer cylinders. End cover has ledge accommodating inner cylinder outer end aligned therewith. First and second spaces are formed between said cylinders. When fluid flows through said spaces extensible cylinder displaces to pulled or pushed position.

EFFECT: drum part that features extension and locking forces higher than those in usual cutting heads.

3 cl, 6 dwg