Internal Hydraulic Valve

Internal "Top Hat" Hydraulic Valve

The Internal Chemical Hydraulic Valve, also referred to as a Top Hat Valve, is a self-closing internal stop valve designed for use on DOT407 and 412 cargo trailers. The stainless-steel valve and all valve components are located inside the tank when installed. 

The⅛1/8" NPT connection is on the outside of the mounting flange and comes with a replaceable PTFE seal. The heavy, flat mounting flange ensures a positive seal.

This valve is tested and verified to meet the requirements of 49CFR §178.345-8


  • Internal self closing stop valve used on dot 407 and 412 cargo trailers
  • 316 Stainless Steel Body
  • Replaceable PTFE Seals
  • Meets requirements of 49CFR §178.435-8
  • MAWP: 50 PSI (3.4 bar)
  • Minimum Bursting pressure: 200 PSI (13.8 bar)
  • Working Temperature range: -40°F to 400°F
  • Hyd. line pressure: Minimum 1500 PSI, Maximum 3,500 PSI
  • Hyd. Volume to fully open: 1.05 in³