EJECTOR DRAG HEAD Russian patent published in 2006 - IPC E02F3/88 

FIELD: hydraulic structures, particularly underwater ground excavation with the use of grad heads.

SUBSTANCE: drag head with hydraulic ripper head member arranged in lower head part comprises body, closure, coaxially arranged suction pipe and mixing chamber, as well as water supply pipe with pressure chamber. Space defined by mixing chamber wall and suction pipe defines annular nozzle with perfectly parallel walls. Replaceable protective armored inserts are installed in mixing chamber. The protective armored inserts are made of steel or cast iron and are used to reduce abrasive wear of mixing chamber walls and to improve degassing of intake ground. Pressure and mixing chambers are communicated through toroidal channel formed in drag head closure. Tapered flanged connectors are used to connect the closure to the body and to secure drag head to water supply and pulp discharge pipelines.

EFFECT: increased operational efficiency due to increased ejector capacity of the drag head and due to possibility of ground lifting from deep locations.

2 dwg