Civacon | Knappco | Sure Seal

16" & 20" Manholes

Civacon offers Petroleum Manhole Assemblies for virtually any petroleum tank truck specification and application; specified by oil companies and transport fleets around the world. Civacon petroleum manhole assemblies are available in plated steel and come in standard sizes of 16" and 20".

These manholes offer unparalleled operational benefits and safety features meeting DOT 406 requirements.  

International assemblies also available.

 Manholes 16
  • Features
  • Model Numbers
  • Downloads

Features and Benefits

  • New and Replacement covers for DOT 406 and MC306 Cargo Tanks; meets HM183 replacement requirements and 178.346-10 venting requirements
  • Designed for Pressure/Vacuum Venting
  • Retrofits to existing weld rings
  • Reversible PAF
  • Buna N Gaskets Standard – optional materials available
  • 10" (260mm) aluminum vent set to open at not less than 3.63 PSI
  • Security Locking feature
  • Lightweight
  • Low profile design

 Part Numbers and Drawings

(click on the part number to view/download parts breakdown and drawing)

16” Manholes:

 16” International Manholes  

 20” Manholes:

20” International Manholes

Brochures • Parts Breakdown • Installation Manuals

 16" Manholes

 20” Manholes