Overview

Pyrotechnic Valves, commonly known as Pyro Valves, are one-shot isolation valves used for on-off flow control of liquid or gasses in missile and space platforms. They are commonly used in propulsion systems, or purge systems and are compatible with many fluids. Normally Closed (NC) valves provide hermetic sealing, assuring no leakage or flow prior to actuation; conversely, Normally Open (NO) valves provide metal-to-metal hermetic sealing, assuring no leakage or flow after actuation.

Principle of Operation

Pyrotechnic Valve assemblies are actuated by an EBAD Series 76 or Space Initiator, or other high-pressure gas generator. In a Normally Closed (NC) valve, gas pressure drives a piston downward shearing hermetically sealed end-caps across the inlet and outlet ports creating a flow passage for pressurized gases or fluids through the valve. Following actuation, internal components are secured in place. In a Normally Open (NO) valve, gas pressure is used to drive a wedge between the inlet and output ports, stopping flow and creating a metal-to-metal hermetic seal. Pyro valves can also be initiated by Flexible Confined Detonation Cord Assemblies (FCDCAs) combined with Thru-Bulkhead Initiators (TBIs).

Pyrotechnic Valves have a Maximum Expected Operating Pressure (MEOP) of 6,000 psig in both pre- and post-actuation modes and meet the highest cleanliness requirements.

Construction

Pyrotechnic Valves are made from Corrosion Resistant Stainless-Steel components that are compatible with liquid or gasses used in the system. The design and construction allow for high pressure sealing capability during and after actuation. The valves are designed to prevent fragmentation or leakage of exploded gasses externally or into the flow passages. Post actuation the internal and external seal is provided by metal to metal seal. The entire assembly is hermetically sealed.

Applications

• • Missile and spacecraft propulsion systems
  • Separation or actuation systems
  • Payload fairing purge systems

Key Features

• • Guaranteed hermeticity
  • High burst pressure
  • Corrosion resistant elements
  • High degree of cleanliness
  • Wide operating temperature range