METHOD AND DEVICES FOR DRIVING BORE-HOLES IN GROUND AT LAYING UNDERGROUND SERVICE LINES UNDER OBSTACLE Russian patent published in 1999 - IPC

FIELD: pipeline construction technology. SUBSTANCE: according to method, driven under obstacle between sending and receiving basins is pioneer bore-hole. Inserted into bore-hole is rod which is connected to working member, then working member is displaced along pioneer bore-hole which is widened to design diameter. In widening of pioneer bore-hole, ground is preliminarily disintegrated by additionally subjecting it to jets of working agent, and then disintegrated ground is directed to ground receiving chamber. In this chamber, ground is mixed with working agent so as to create slurry which by means of ejector pump is transported to slurry pipeline. As bore-hole is being formed, delivered into it is thixotropic solution. Devices for creating bore-holes in ground has following components: hollow cylindrical body, ground cutter, ground receiving chamber. piping for delivery of working agent, distributing pipe union, nozzles for discharge of working agent, mechanism for displacement of body in the form of hollow rod, ejector pump, slurry pipeline, distributing chamber with holes for outflow of thixotropic solution and with pipe union for connection to pipeline which delivers thixotropic solution. In one of versions, ground cutter is made in the form of strip-like blades. Distributing pipe union is made in the form of sleeve. In other case, ground cutter is made in the form of cutting bit. Distributing pipe union is installed for possible rotation relative to hollow cylindrical body. Application of aforesaid method and devices is characterized by higher bore-hole driving accuracy, reduced power demand with simultaneously improved quality of walls in created bore-hole. EFFECT: higher efficiency. 5 cl, 6 dwg