Basalt fibre offers an alternative to carbon and glass in the filament winding of compressed natural gas cylinders. The theoretical and practical study carried out by Russia-located Kamenny Vek proves that basalt is a promising material for CNG cylinders.
All the advantages of basalt fibres – higher tensile strength, modulus, high chemical resistance, the possibility of recycling, and an extended range of working temperatures – can be realised in filament wound components.
The manufacture of compressed natural gas (CNG) cylinders is growing rapidly worldwide. This is in line with growing demand from the automotive industry for cheaper and ecologically ‘cleaner’ fuel, and in particular compressed natural gas. However, the use of CNG creates the problem of gas storage and safe transportation. Vessels for CNG storage (CNG cylinder) must be strong, lightweight, and resistant to impact and temperature. At present, cylinders can be divided into the following three groups, depending on the materials used in their manufacture:
- metal-composite (metal liner strengthened by polymer composite material); and
- composite (polymer liner strengthened by polymer composite material).
Today, all three groups are widely available on the market and each has its own advantages and disadvantages. For example, the weight of metal cylinders is a serious disadvantage.
The weight of a cylinder can be reduced by partially replacing the metal with a lower weight polymer composite material as well as replacing the metal liner with a polymer liner.
In this case the cylinder maintains its durability because of the high strength, lightweight epoxy impregnated carbon fibres used. But the extremely high price and current shortage of supply of carbon fibre may force manufacturers of CNG cylinders to look for an alternative material.
Basalt fibre, which has better mechanical properties than E-glass fibre and is more widely available and cheaper than carbon fibre, could be a good alternative in this application.
Dmitri Pavlovski, Boris Mislavsky and Andrey Antonov