CARGO TANK OVERPRESSURIZATION AND PROCEDURES FOR VENT SYSTEM EVALUATION AND DESIGN

Venting systems are employed on marine vessels to relieve pressure differences which arise between the cargo tank and atmospheric pressure. In the case of closed gauging or a vapor recovery system, there will be a pressure rise in the tank which depends upon the cargo pumping rate and the vapor relief capacity of the vent system. If the system does not have the proper capacity, or if there is an accidental overfill, tank failure may occur. Analytical methods determining the pressure rise in marine cargo tanks during cargo transfer were developed and confirmed by scale-model experiments. A study of typical vent systems in use today shows that these systems have more than adequate capacity for gas venting, but inadequate capacity for liquid overfill. Cargo volatility has a relatively small effect on hazard evaluation, but many cargo transfer operations currently equal or exceed permissible overfill loading rates. Furthermore in these instances of tank overfill, tank failure is expected within a very short time (less than one minute). A method for evaluating overpressure hazard during cargo transfer operations is presented.

  • Supplemental Notes:
    • Presented on 19 March 1980 to the Chesapeake Section (SNAME).
  • Corporate Authors:

    Society of Naval Architects and Marine Engineers

    601 Pavonia Avenue
    Jersey City, NJ  United States  07306-2907
  • Authors:
    • Flessner, M F
    • Swanek, R A
    • DINSENBACHER, A L
  • Publication Date: 1980

Media Info

  • Pagination: n.p.

Subject/Index Terms

Filing Info

  • Accession Number: 00311544
  • Record Type: Publication
  • Report/Paper Numbers: Conf Paper
  • Files: TRIS
  • Created Date: Jun 9 1980 12:00AM