About Stone Wool

What is Stone Wool?

Volcanic wool Insulation is a form of stone wool insulation, all products developed by Volcanic wool are created using naturally occurring stone which are common to South Africa, namely dolomite and dolorite.

The process begins when dolerite is mixed with dolomite and loaded in accordance with a specific formula into a cupola furnace which has a temperature of 1500 °C. The Cupola furnace is responsible for melting the stones into molten lava using a specific form of coal known as “coke”.

The lava which is produced during the melting process then flows to the spinning machine which rotates at high speeds in order to create individual fibers of insulation. During the spinning process, a mixture of resin with a hydrophobic agent is added to the newly spun fibers which assists in bonding the loose fibers together.

After being sprayed with the binder mixture, the fibers are then ready to continue into the felt-forming chamber which collects the fibers and spreads them across the conveyor belts in order to form an evenly distributed layer of insulation.

The newly formed layer is then fed by a conveyor system to the pendulum machine which stacks each insulation layer formed onto one another in order to obtain the correct weight for the products.

The now formed bulk insulation then continues to the crimping machine which compresses the bulk insulation layers into one firm sheet of insulation. The crimping machine assists to ensure the correct technical properties of the material such as compression, rigidity and thickness.

Once the insulation has passed through the crimping machine, it enters the curing oven. The curing oven slowly heats the material in order to cure the binder sprayed during the spinning process and ensure any excess binder is removed.

The felt that comes out from the curing oven is now ready for the next step which is cutting it according to the required dimensions. This begins with the material passing through an edge trim machine which cuts off any excess material from the sides of the bulk insulation sheet creating a perfectly smooth edge and ensures the correct width for the product. The material then continues on the conveyor belts and reaches the cross-cutting saws which cuts the material according to length thus creating the final product. Different dimensions can be achieved by simply adjusting the cross-cutting saws position during the cutting process.

The final step of the process entails packing and compressing the product whilst ensuring it meets the quality standards of Volcanic wool.

Volcanic Wool Stone Wool Benefits

VOLCANIC WOOL stone wool is made of 100% natural stone. We do not use slag in our production. Slag is the metal manufacturing waste product. When used in the stone wool production it may decrease the price for the materials but at the same time decreasing the products thermal properties.

Structure of fiber
The main advantage of VW insulation products is its structure. The fibers of the material are chaotically interlaced which gives VW insulation products increased stability and prepares it for extreme conditions and uses. VW insulation has a life span of 50 years whilst maintaining its technical properties throughout this time. The structure of the material also results in the excellent acoustic properties Volcanic wool products possess.

Acoustic Properties
Volcanic wool stone wool insulation products have a porous and open cell structure that makes the process of absorbing sound much more efficient. This assist with sound transmission and noise reduction by having the highest properties from all mineral fiber-based insulation products.

High Thermal Properties
VWI insulation product has the best thermal conductivity coefficient from mineral fiber insulation which makes it difficult for heat to be transferred through the insulation. For example, a VW product of 100 mm thickness, a wooden block of 400mm thickness and a brick wall of 2000 mm thickness will have the same thermal conductivity properties however, the costs for the bricks or wooden block will be much higher and take up a lot more space as opposed to Volcanic wool products. This also means that you will be able to achieve the required R values as per SANS 10400-XA whilst using a thickness of 110mm only vs the industry standard of 135mm.

Fire Safety
VWI Product is made of stone which is naturally resistant to fire. Even at temperatures of 1000C, the fibers of our product will still stay interlinked which results in the structure of the material being stable for much longer periods, thus allowing added fire protection whilst maintaining structural integrity of buildings.