Fireworks are a type of explosive device that come in a variety of different colors and sizes. They are used primarily for entertainment at large events such as sporting activities and celebrations. The earliest fireworks are dated back to 7th century China where they accompanied many festivals and celebrations. In most countries personal fireworks are illegal, so firework displays are run by professional pyrotechnics. Fireworks are designed to create 4 effects: sound, light, smoke and floating materials. The most common colors that fireworks come in include blue, red, green, silver, yellow, orange and purple.
How are fireworks made?
Fireworks are made up of 5 main parts, the shell, the plug, the fuse, the explosive and the effects.
The shell is usually constructed from heavy duty cardboard or metal. The cardboard is fashioned into a cylinder. Most firework manufacturers use a machine to roll the tubes. These tubes are then either fitted together to make multiple shot fireworks or left as single tubes.
Each tube is then plugged using clay to prevent excess pressure and chemicals from being released. A sleeve is placed around the tube to help maintain its shape, and clay is fitted into the top of the tube. A rammer is then used to push the clay securely to the bottom of the tube. A heavy tool such as a mallet or a specialized machine applies pressure to the rammer to ensure the clay is compacted.
Small holes are drilled into the bottom of the tubes above the clay plug. The fuse for the firework is threaded into this hole to give it direct contact with the explosive material. In the case where numerous tubes are attached together the main fuse is threaded through each tube.
Once the shell, plug and fuse are in place the firework casing is ready to receive the explosive material. This material is usually black powder and is measured carefully to ensure the right amount of explosive material is added. This explosive material sits in the bottom of the tube and is what is responsible for igniting the effects and propelling the effects into the sky.
The final part of the firework is the effects. This is the sound, light and color that you see when a firework explodes. These effects are contained in a small shell called an aerial effects tube. In these tubes there are small pellets or sparkler type material called stars which produce the flares in the sky. These pellets can be spheres, cubes or cylinders depending on the effect they will create. How the stars are arranged inside the aerial effects tube determines their arrangement in the sky.
Other chemicals are packed into the tubes to give the fireworks particular colors and sounds. These substances are all bound together using a binding agent and the top of the firework covered with a thin cardboard or paper top.
It is important that you do not try and make your own fireworks; Fireworks need to be constructed correctly so that they function as they should. It is also important not to make your own fireworks as they can malfunction and cause serious harm and even death.