Methods for making light-weight drainage line units
US5535499A · kind A · utility
Inventors
Key dates
| Filing date | May 31, 1995 |
| Grant date | Jul 16, 1996 |
| Priority date | — |
| Expiry date | May 31, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49982
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method for manufacturing preassembled drainage line units comprises feeding a length of perforated vent pipe along a direction of manufacture longitudinally through a tubular mandrel, feeding a continuous sleeve of netting concentrically over the vent pipe along the direction of manufacture from a front end of the mandrel and continuously supplying quantities of artificial aggregate into the space between the sleeve of netting and the vent pipe. A low friction coating is applied to the inside surface of the mandrel to reduce the surface friction of the artificial aggregate caused by compaction, and to permit high speed manufacture.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.