ParaFence™ is a lightweight windbreak fencing which has the ability of reducing wind speed by up to 90%. The system is made from high strength polyester filaments encased in a polyethylene to compose horizontal and vertical webs. It has been proven across the world in a wide variety of applications ranging from the protection of industrial plant and equipment, through mining and quarrying to farming and horticulture. ParaFence has been used widely to provide effective windbreaks on railways and open highways.
The scientific key to the success of ParaFence is ‘controlled porosity’. When solid structures are used as windbreaks they can have the effect of actually increasing wind damage. They cause the wind flow to rise over the structure, creating an area of low pressure and a partial vacuum to the leeward side. The vacuum tends to pull the free stream downwards, quickly negating the windbreak effect. This situation is worsened because friction between the free stream and the vacuum can generate high speed turbulence capable of causing more damage than the original wind.
ParaFence is engineered to avoid this problem. It is manufactured from a series of horizontal and vertical webs which result in carefully designed ‘controlled porosity’. This design allows a diffused flow of wind to pass through to the leeward side. Although travelling at a much slower speed, this flow is closer to equilibrium with the higher energy free stream flow maintaining the maximum possible length to the protected zone behind the fence.
WHY CHOOSE PARAFENCE?
- Offers direct protection from the wind by reducing wind speeds before they impact a structure, area or facility
- Controls and prevents "pick up" of particles such as snow and dust that are caused by the wind and their deposition from transport
- Reduces thermal losses by the controlled installation of an engineered wind break structure
- Lightweight, easy to handle
- Tough and durable with its high impact & tensile strength
- Retains tension once installed
- Virtually maintenance free
- Resistant to sunlight, rain and salt water
- Does not interfere with drainage or irrigation systems
Assembly of the fence structure is carried out on a purpose-designed machine that welds the horizontal and vertical members together. Horizontal webbings are, typically, 50mm wide and 50mm apart although a wide variety of variations is possible.
Typical nominal breaking loads (NBL) for the horizontal webs are 165kg, 400kg and 1000kg with widths of around 50mm. ParaFence is supplied in rolls of 30m in five standard heights – 2.2m, 2.0m, 1.8m, 1.4m and 1.0m which are constructed from the following number of horizontals; 22, 20, 18, 14 and 10 respectively. ParaFence is most usually supplied in black to provide the highest UV resistance but is also available in orange, light green and dark green.