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Blasting Works With Royex Cartridges

What is Royex?
Royex is a rock breaking system consisting of cartridges, deployment accessories and coverage. The Royex cartridge is based on a non-detonating propellant enclosed in a plastic housing with electrical ignition. During ignition, the burning propellant generates a fast expanding gas volume consisting mainly of nitrogen, water steam and carbon dioxide. If properly applied inside a drill hole, the expanding gas will fill the small natural fractures existing in the rock. The gas will expand the natural weaknesses of the rock into the nearest free face. This results the rock fractures to expand and the rock to break.

What is the purpose of Royex?
Royex was developed as a response to the increasing need for a safe alternative to conventional explosives. In situations where conditions require sensitive operations, conventional explosives could be difficult or impossible to use due to the risk of collateral damage and rock / ground vibrations. The safety risk of fly rock and blast damage is a constant issue for excavations and blasting in populated areas or close to sensitive infrastructure. Royex offers a solution where the desired result of using explosives can be obtained but without the risk of blast damage, fly rock and ground vibration. Royex is thoroughly tested in a multitude of situations and rock formations. The system can be tailored made to fit any type of sensitive condition.

What is the differences between conventional explosives and Royex?
Environmentally safe

-Using no coverage, Royex causes minimal fly rock. With properly applied coverage, fly rock can be completley eliminated.
-Ground vibrations are kept to a minimum. Working adjacent to foundations or housing structures are no issue.
-Noxious gases emitted upon initiation are a negligible.
-Overpressure levels are significantly lower compared to conventional explosives.
-If coverage is properly applied, Royex noise levels are very low.
-Only very local clearance of personnel and equipment are required which means shorter downtimes for moving and preparing equipment.

Efficient results

-Royex gives the same results as conventional explosives for small diameter drill holes.
-Cartridges are available in a multitude of sizes, enabling tailor made results with high precision.
-A 50 g 32 mm Royex cartridge typically breaks 1 m³ hard rock in normal conditions. This figure can be significantly higher in secondary breaking applications.


Why should I use Royex instead of mechanical rock breaking tool?
Mechanical rock breaking denotes the usage of hydraulic tools, wire sawing and splitters to break rock. The advantages of using Royex ahead of such an approach are among others;

-Investing in mechanical rock breakers constitutes a significant cost compared to Royex. They are also subject to routine maintenance costs..
-Mechanical rock breakers are significantly less effective in terms of broken rock per time unit.
-In difficult operations, it could be difficult to physically fit a rock breaking rig close enough for operations. For applying Royex, a small, simple hand held drill is sufficient.
-Mechanical rock breaking normally causes higher (and more continuous) noise levels than properly covered Royex cartridges.


What ground / rock vibrations are generated by Royex?
The rock breaking effect of the Royex cartridge comes from the rapid gas expansion generated from the deflagration process of the propellant. This gas expansion generates a rapidly growing pressure (and temperature) which in turn generates a pressure wave in the surrounding rock. The energy of this pressure wave decreases as the distance from the pressure origin (the drill hole) increases. How fast this decrease happens depends on the amount (weight) of propellant used, where the measurement takes place (how far between the drill hole and the measurement equipment) and the rock conditions and quality.

Are the vibrations produced by Royex safe for sensitive structures?
Generally yes. This of course depends on the rock conditions and the proximity to the sensitive structure. The rule of thumb in regards to dangerous ground vibrations are;
PPV < 50 mm / s generally safe PPV > 50 mm / s possible damage
The above is a general rule for vibration frequencies above 40 Hz. Royex vibrations are above approx. 400 HZ. Which puts Royex ground vibration to the lower end of safe scale. These levels are very difficult to achieve with conventional explosives and this makes Royex a alternative in sensitive areas where conventional blasting is prohibited. For Royex vibration test reports, please view documentation archive.

How much noise does Royex produce?
Noise levels are strongly dependent on the type of rock being broken and the application of coverage. Generally, noise levels above 80 decibel are very rare. If proper coverage is applied, levels around 55-60 dB are normal.

What are the safety distances recommended for Royex?
The safety distance recommended is strongly dependent on load weight, coverage and site geography. Properly covered and planned drilling and charging normally only requires clearance of about 30 meters. As a result, the site does not require shut down of parallel operations.