Make your own free website on Tripod.com








CHECK VALVES














HOME | C803-CFR | IN MEMORIAM | V. I. P. = V. I. P | SITE MAP | ALPHABETIC MAP | GLOBAL LAWS | ETHANOL | ATMOSPHERE | COPPER/PLASTIC | DISTILLATION | FEEDSTOCK$ | FERMENTATION | BOILER / REBOILER | HEAT EXCHANGER | GO SOLAR | TOOLS | ELECTRO | ENGINES | S.E.E.F.A | LINKS | REFERENCES | APPENDICES | DOWNLOADS | ETHANOL FUEL MANUAL | FACTS





Enter subhead content here
















      •  CHECK VALVES 
  • Check valves are unidirectional flow control devices used to eliminate potential damage caused by backflow.
  • Flow in the desired direction will cause a mechanism such as a piston, disc, or ball to open the valve, while backflow causes the valve to close.
  • Check valves with a soft seat (such as Buna-N, Viton, and PTFE) provide a bubble-tight shutoff.
    • CRACKING PRESSURE is the minimum psi required to open a valve.
      • TEST DEVICE TO DEFINE CRACKING PRESSURE
  •  SPRING LOADED CHECK VALVES (also known as silent check valves) have a spring-assist mechanism (controlled by the flow) to open and close the valve. For horizontal and vertical use.
  • BALL CHECK VALVES use a free-floating ball, which "unseats" to permit flow in the desired direction and "seals" against the seat to prevent backflow. While fluid is flowing, the ball rotates constantly, equalizing wear on the ball and valve seat. They can be installed horizontally and vertically in upflow applications, and in downflow applications if spring loaded.
  • SWING CHECK VALVES direct flow through the use of a swinging disc, which requires only minimal back pressure to close the valve. Swing check valves with a spring seat faster.
    • They can be installed horizontally and vertically (when installed vertically, flow must be upward)
  • Vertical-lift (gravity) check valves have a disc floating in the seat that opens by upward flow pressure.
    • For vertical piping runs only.

__________________________________________________________________

  • Cv FACTOR (coefficient of volume) is the amount of water (in gpm) that will pass through a fully open valve at 1 psi with 1 specific gravity (60  F). For pressure drop other than 1 psi, use this formula:

_________________________________________________

Click to change image size
















Enter supporting content here