MULTIPLE PISTON ASSEMBLY FOR SAFETY VALVE

摘要

A safety valve includes a housing defining first and secondary piston bores in fluid communication with each other via a port, a first piston movably arranged within the first piston bore and having a first piston rod extending longitudinally therefrom and coupled to a flow tube, and a second piston movably arranged within the secondary piston bore and having a secondary piston rod extending longitudinally therefrom and axially engageable with the flow tube, wherein hydraulic fluid pressure acts on the first piston until the first piston axially moves and exposes the port, whereby the hydraulic fluid pressure is then able to enter the secondary piston bore and also act on the second piston.

主权项

1. A safety valve, comprising:
a housing defining a first piston bore and a secondary piston bore in fluid communication with each other via a port, the first piston bore being configured to receive hydraulic fluid pressure therein and the secondary piston bore being configured to receive the hydraulic fluid pressure from the first piston bore via the port; a first piston movably arranged within the first piston bore and having a first piston rod extending longitudinally therefrom and operatively coupled to a flow tube such that axial movement of the first piston correspondingly moves the flow tube; and a second piston movably arranged within the secondary piston bore and having a secondary piston rod extending longitudinally therefrom and axially engageable with the flow tube when the hydraulic fluid pressure acts on the second piston, wherein the hydraulic fluid pressure acts on the first piston until the first piston axially moves and exposes the port, whereby the hydraulic fluid pressure is then able to enter the secondary piston bore and also act on the second piston.