Apparatus for making a drainage element

摘要

An apparatus is provided for making drainage elements in a vertical manner. In one embodiment, a vertically disposed hollow rotatable mandrel with a screw-threaded flight is used for guiding a length of perforated pipe and filling an annular space between the pipe and a cylinder of mesh material secured at one end to the pipe with aggregate. A hopper is used for directing the aggregate into the space between the mandrel and a cylindrical outlet of the hopper. A motor for driving the mandrel may be reversed at a slower speed than the forward speed to stop delivery of aggregate and to allow time for the upper end of the cylinder of mesh material to be severed and secured to the pipe to form a drainage element as well as to allow severance of the pipe. In another embodiment, the perforated pipe is driven through the hopper and the aggregate flows under gravity into the mesh sleeve.