Flushing hydrant with fail-safe
View Patent ↗A device for flushing a hydrant includes a stem connected to a fluid valve of the hydrant and an actuation system including a biased translational system coupled to the stem, a compressed gas, and a normally-open gas discharge valve. An actuation system for flushing a hydrant includes a fluid, a piston assembly movable by the fluid, a manual bleed valve in communication with the fluid, and a biasing element at least indirectly biasing the piston assembly towards a stop position.
1. A device for flushing a hydrant comprising:
a stem connected to a fluid valve of the hydrant; and
an actuation system including:
a biased translational system coupled to the stem;
a compressed gas;
a normally-open gas discharge valve;
a normally-closed gas intake valve and
a hold down assembly coupled to the stem and defining a pressure cavity in fluid communication with the normally-open gas discharge valve and the normally-closed gas intake valve, the pressure cavity including a piston plate within the pressure cavity.
2. The device of claim 1 , wherein the gas discharge valve includes a solenoid and a pneumatic valve, the pneumatic valve closable by the solenoid.
3. The device of claim 1 , wherein the hold down assembly includes a stem body defining a bias cavity and the pressure cavity, wherein:
within the bias cavity, a biasing element of the biased translational system is seated; and
within the pressure cavity, a piston assembly includes the piston plate, a cylinder body, a bottom plate, and a bottom plate stop, wherein the piston plate separates the pressure cavity into a top chamber and a bottom chamber, wherein the top chamber and bottom chambers are sealed, and wherein the top chamber is in fluid communication with the normally-open gas discharge valve and the normally-closed gas intake valve.
4. The device of claim 1 , wherein the actuation system includes at least one gas container.
5. The device of claim 1 , wherein the hold down assembly includes a stem body coupled to the stem.
6. The device of claim 5 , wherein the stem body defines the pressure cavity.
7. The device of claim 6 , wherein the stem body includes a piston assembly within the pressure cavity, the piston assembly including the piston plate.
8. The device of claim 1 , wherein the biased translation system includes a biasing element.
9. The device of claim 8 , wherein the biasing element is a spring, the spring surrounding the stem.
10. An actuation system for flushing a hydrant comprising:
a fluid;
a piston assembly movable by the fluid, the piston assembly including a piston plate within a pressure cavity defined in a hold down assembly;
a normally-open fluid discharge valve in fluid communication with the pressure cavity;
a normally closed fluid intake valve in fluid communication with the pressure cavity;
a manual bleed valve in fluid communication with the pressure cavity; and
a biasing element at least indirectly biasing the piston assembly towards a stop position.
11. The actuation system of claim 10 , wherein the manual bleed valve is a manual piston purge valve.
12. The actuation system of claim 11 , wherein the manual piston purge valve is openable by a wrench.
13. The actuation system of claim 10 , wherein the hold down assembly is mountable on a hydrant.
14. The actuation system of claim 10 , wherein the fluid is compressed gas.
15. The actuation system of claim 14 , further comprising at least one gas container.
16. A method of flushing a hydrant comprising:
operating an actuation system coupled to the hydrant, the actuation system including a compressed gas, a normally-open gas discharge valve, a normally-closed gas intake valve, a piston assembly coupled to a stem of the hydrant and including a piston plate within a pressure cavity defined in a hold down assembly, the pressure cavity in fluid communication with the normally-open gas discharge valve and the normally-closed gas intake valve, and a biasing element coupled to the stem, the stem connected to a fluid valve of the hydrant;
closing the normally-open gas discharge valve; and
opening the fluid valve of the hydrant by pressurizing one side of a piston plate of the piston assembly with the compressed air.
17. The method of claim 16 , further comprising closing the fluid valve of the hydrant by opening the normally-open gas discharge valve, wherein opening the normally-open gas discharge valve releases pressure from against the one side of the piston plate.
18. The method of claim 16 , wherein the piston assembly is mounted within a pressure cavity defined within a stem body coupled to the stem.
19. The method of claim 16 , wherein opening the fluid valve includes opening the normally-closed gas intake valve of the actuation system.
20. The method of claim 16 , wherein the normally-open gas discharge valve includes a solenoid, and wherein closing the normally-open gas discharge valve includes powering the solenoid.