Precast invert of sewerage manhole capable of controlling connection angle and length

摘要

PURPOSE: A sewer manhole precast invert is provided to improve construction efficiency and to reduce the time and manpower required for construction. CONSTITUTION: The sewer manhole precast invert whose connection angle and length are adjustable according to field conditions, as a precast invert for setting up newly or settling a precast invert(6) to the existing manhole to construct the optimum invert to a sewer manhole, is made with rubber or resins to adapt to a construction field to set to the connecting form of an inflow pipe(2) and an outflow pipe(3) and contains an elastic horizontal iron core to prevent sectional transformation by horizontal pressure, a plastic vertical iron core attached longitudinally to keep a control angle when fixing a precast invert, a protective film attached into the invert to prevent a rise of the illumination factor by pollution of the invert when placing concrete around the precast invert(6), and a fixed pin(13) to attach invert concrete and the precast invert(6).