System and filter for preventing contamination of particulate material in railroad car during transportation and unloading
US4902173A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 1988 |
| Grant date | Feb 20, 1990 |
| Priority date | — |
| Expiry date | May 20, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D46/02
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A system for preventing contamination of particulate material in a railroad hopper car during transportation and unloading of the material from the car, comprising transporting the material in the railroad hopper car with a filter on each of the various inlet and outlet openings of the car, then upon reaching the point for unloading, applying a vacuum to draw the material out of the car through one spout with its filter removed, while leaving the filters in place on the other openings in the car to prevent contamination of the product from external sources during transportation and unloading. The preferred filter for the railroad car spouts has a frame, a conical filter bag, and a filter bag support ring for mounting on a spout on the car.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.