TRENCHLESS LAYING OF GRAVITY SEWER Plumbing by Lisa Dean - March 8, 2021March 10, 20210 Do you need to develop a project and carry out a sewerage system to a residential building, in a summer cottage settlement, or to carry out the removal of sewerage networks from under a building spot? DVN-Story designs and installs external sewerage in an open way, as well as using various trenchless methods, including the use of HDD Vermeer installations. More detailed information on open sewerage installation (as well as installation of wells, installation of treatment facilities, installation of a sewage pumping station and an extinguisher well, sewerage tie-in) can be found in the section laying of water supply and sewerage systems Features of the trenchless laying of gravity sewer using HDD method Trenchless sewer pipe relining installation with a given slope is also possible using the HDD method, however, it is limited by some features of this method, namely: The transmitter transmits information about the tilt of the drill head in percent or degrees with a step of 0.1% in the vertical plane, which allows you to achieve the desired slope of the sewer. However, in the horizontal plane, the operator-locator does not have such accuracy, therefore, in some sections, the pipe, after being pulled through when receiving through the light, may have the shape of an “incomplete moon”; The size of the borehole is 1.3-1.5 times the size of the pulled pipe, depending on the diameter and length of the section. Under the influence of the Archimedean force, the hollow pipe is pressed against the upper arch of the well, but in the presence of any obstacle (boulder, construction debris, etc.), the pipe bends around it, respectively, this section may have an error; Signal accuracy during trenchless sewer pipe relining installation using the HDD method can be affected by various sources of interference, for example, electric cables, metal structures, cathodic protection systems, fittings, and reinforced concrete slabs, high-voltage power lines. In this case, the signal of the emitter probe may be distorted (indicate a deliberately false depth, give different results at the same time of measurement) or it may not be at all; Difficult geological conditions: the presence of construction waste, man-made deposits, stones and boulders, weak non-bearing soil (quicksand). The drill head usually bypasses obstacles to the side, along the path of least resistance, and with a significant size of the obstacle rests against it. However, in spite of the above factors, trenchless installation of gravity sewerage using the HDD method is possible with a good result, with careful engineering preparation of the facility and the proper level of professionalism of the drilling crew. Special requirements for a gravity drainage system are imposed on the locating system operator and the drilling rig operator. The company “DVN-Stroy” successfully carries out work on the installation of gravity sewerage by the method of horizontal directional drilling, followed by the delivery of work to the operating organization.