Railway tie of non-homogeneous cross section useful in environments deleterious to timber
US7942342B2 · kind B2 · utility
1Cited by
55References
20Claims
0Family size
Inventors
Key dates
| Filing date | Apr 25, 2007 |
| Grant date | May 17, 2011 |
| Priority date | — |
| Expiry date | Aug 1, 2028 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE01B3/46
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A railroad tie comprises a core comprising wood or a wood product, and a first sleeve encapsulating the core, wherein the first sleeve comprises at least one of the group consisting of plastic, plastic-composite, or non-plastic polymers. A second sleeve may additionally encapsulate the first. In a preferred embodiment, the first sleeve is comprised primarily of poly ethylene terephthalate, and the second sleeve is comprised primarily of high density poly ethylene.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.