An Introduction To Pyro Devices

The Importance Of Pyrotechnic Devices

According to man-rated systems and other missile and space programs these devices need to be highly reliable.?

The manufacturer of CADs, PADs, and linear product must be very exact. In that exacting environment, we can produce products that have as many as three, four or five nines of reliability working at a very high confidence level. Most of these devices are small (some as small as 1” by 2”) but they pack a high level of energy.

Lastly, pyro devices are used on a broad spectrum of applications. Quite literally, CADs, PADs and linear products are used from deep sea to deep space.

All About Energetics

An energetic is a chemical material that contains reactive substances and a large amount of potential energy.

Primary Explosives

Primary explosives are initiated by friction, shock, or heat. At PacSci EMC, we use this energetic in many different places to start the explosive train. Examples of primary energetics include Lead Azide, Lead Styphnate, DBX-1 (a green replacement for Lead Azide), and KDNP (a green replacement for Lead Styphnate).

Secondary Explosives

Secondary explosives require a strong shock to initiate. Once initiated, they provide a shockwave and high pressure which travels at supersonic speed. Common high energy explosives like HNS, PBXN-5, HMX, RDX and PETN are used in aerospace and defense and some commercial oil and gas operations.

Deflagrating Material

We also have deflagrating material which is an energetic producing a flame propagation and transfers heat and mass at a subsonic speed. Rapid Deflagrating Material (RDM) is proprietary to PacSci EMC and is used in transfer lines in aircraft systems to aide emergency escape. Other deflagrating materials include Auto-Ignition Materials (AIM), Time Delay Compositions and Ignition Materials.

Propellants

Propellants are chemical materials that produce gas byproducts to create thrusts. At PacSci EMC, the most common propellants are Ammonium Perchlorates and Ammonium Nitrates.

Cartridge Actuated Devices (CADs)

A Cartridge Actuated Device is a component that receives an input stimulus to initiate an internal cartridge providing an output to active explosives or other components.

The inputs to initiate can be electrical, pressure, detonation, mechanical, or even LASER. Outputs can be electrical pressure, detonating, or mechanical. To do an electrical output, we use devices called Pyro Switches. When the switch is closed, power is allowed to run through. Other devices may use a chemical reaction within the CAD.

Propellant Actuated Devices (PADs)

Propellant Actuated Devices are a normally compact envelope and utilize the energy supplied by reacting propellants to initiate a mechanical action. As an example, that mechanical action could be an Engine Start Cartridge, a Pyro Igniter, or a Gas Generator.

The inputs could be electrical, hot gas or mechanical. The output is normally a gas pressure but could also be a flame.

Linear Explosives

Linear explosives are basically explosive powder or material that’s drawn in a continuous metal sheath. Inputs for a detonating material need to be another detonation or high shock. For deflagrating type materials in a metal sheath, it should be a detonation, flame, or heat input. Outputs will be detonation shockwave for Mild Detonating Cord (MDC), Mild Detonating Fuze (MDF) and Linear Shaped Charges (LSC). Rapid Deflagrating Cord (RDC) and Auto-Ignition Material Cord (AIMC) material would have pressure or a flame as outputs.

To learn more about the world of pyrotechnics, please visit this page: https://psemc.com/allfire/allfire-volume-3-no-2/