Universal working mechanisms of hydraulic machines
for trenchless pipeline rehabilitation

Summary

The advanced technology of trenchless rehabilitation of old pipelines with the use of hydraulic machines with the working mechanism that includes a cutter block with disk blades and a conical expansion tool is considered. Shockless pipe destruction provides for reducing significantly the risk of soil sloughing and damage of the adjacently laid underground utilities. The analysis of similar working mechanisms of the hydraulic machines for trenchless pipe renovation (Grundoburst Tracto-Technik, Germany, and Hydro Burst Vermeer, USA) revealed a number of drawbacks consisting in the limited application area and low level of versatility of these working mechanisms that did not provide for pulling through a new plastic pipe of extended length; repairing pipelines with bends and turns; renovating pipelines of wide diameter range with the use of a single equipment set. Three prototypes of the working mechanism based on hydraulic machines were manufactured and tested. The first prototype provides for pulling through a new plastic pipe that is 1.5–2 times longer (to 200 meters and more). The second is designed for the renovation of pipelines with up to 45 degrees bend angle. Adding joint assembly links allow increasing the bend angle (to 70 degrees). The third prototype is designed for renovating pipelines of various diameters (fracture from 150 to 200 mm) with the use of a single set. This design makes the given technology more simple and cheap. The suggested designs of the universal working mechanisms based on hydraulic machines provide for trenchless pipeline rehabilitation under various operating conditions.

Key words

pipeline , trenchless repair , hydraulic machine , working mechanism , pulling part