Ground penetrating rocket tool for boreholes - has chisel combined to form cruciform cutter with longitudinal rocket ribs

摘要

The ground penetrating tool for boreholes has a body accommodating the propulsion unit. The cutting head (14) is narrow and forms a cutting edge(20) normal to the forward travelling direction. The cutting edge is symmetrical to a longitudinal midplane. Guide ribs (28a, 28b) project beyond the outside envelope of the rocket body on both sides of this first longitudinal midplane. The guide ribs project in longitudinal direction of the rocket body up to the region of the cutting edge (20). These guide ribs form a cruciform cutter together with the cutting edge.