BLOCKAGE OF FLAME CONTROL DEVICES: DESIGN AND MAINTENANCE CRITERIA
A study was conducted of the blockage of flame control devices and the effect of flow constriction on the pressure- relief function of the venting system. It was found that the open area must be almost completely blocked before the tank pressure would rise significantly (e.g., 93% blockage to produce 3 psig at 30 ft/sec normal venting speed). The available evidence suggests three blockage mechanisms occur with significant frequency: (a) plugging by liquid cargo due to condensation or overfill; (b) polymerization of monomer- type cargoes; and (c) corrosion by cargo vapor or moist air. Seven cargoes were found to present a significant polymerization hazard (acrylate and methacrylate esters, formaldehyde, acrylonitrile, butadiene, styrene, vinylidene chloride, and vinyl acetate) the characteristics of these materials were tabulated along with recommended use of inerting or inhibitors. The corrosion potential of 50 cargoes used with each of 20 metals was evaluated; out of 1000 combinations at least 130 were found unsuitable, with magnesium- and copper-based metals accounting for 90% of the unsuitable cases.
Little (Arthur D), IncorporatedAcorn Park
Cambridge, MA United States 02140
- Wilson Jr, R P
- Gott, P G
- Publication Date: 1975-8-1
- Pagination: 56 p.
- TRT Terms: Fire extinguishing agents; Hazardous materials; Tanks (Containers); Ventilation systems
- Old TRIS Terms: Flame arresters; Tank venting
- Subject Areas: Marine Transportation; Safety and Human Factors;
- Accession Number: 00128765
- Record Type: Publication
- Source Agency: National Technical Information Service
- Report/Paper Numbers: USCG-D-158-75 Final Rpt.
- Contract Numbers: DOT-CG-42357-A
- Files: TRIS
- Created Date: Jan 21 1976 12:00AM