Compositz Insulators weigh less than half the weight of an equivalent string of porcelain or glass disc insulators. Added to this health aspect is the safety feature that Compositz Insulators do not shatter, break or cause any harm to personnel in the case of misadventure. Silicone rubber is also softer than EPDM in that the sheds are pliable. This feature allows greater safety in handling the Compositz Insulators.
Also, since the weight of each insulator is less, then the packaging that it comes in is more efficient. There is less packaging, less nails protruding from cases and less clean-up and waste at site.
Silicone rubber's superior capacity to bead water, make Compositz Insulators better than glass, better than porcelain and better than ethylene propylene (EPDM) rubber. While most composite insulators demonstrate the ability to bead water when new, all but silicone rubber insulators eventually degrade under contaminated conditions and over long periods of time. The hydrophobic properties of silicone rubber prevent reduction in the dielectric properties of the insulation system.
Compositz Insulators are not subject to high leakage currents, because regardless of the amount of contamination present on the insulator, silicone rubber can continuously bead water. This insures lower line losses and consistent flashover values over the life of the transmission line.
The remarkable qualities of silicone rubber's leakage performance allow for a reduction by 30% of the equivalent leakage distance required for porcelain and glass. Consider the different current carrying capacities between copper and aluminium conductors of the same size. The atomic structure of silicone rubber too changes the leakage requirements over porcelain and glass. This 30% reduction in leakage requirements can influence the design height of transmission structures, or provide a greater factor of safety on existing structures.
To prove the superiority of silicone rubber, laboratory and field tests were conducted on Compositz Insulators alongside equivalent porcelain and glass designs. With 30% less leakage inches versus standard porcelain designs at 230kV, the Compositz Insulator demonstrated flashover at voltage levels 30% higher than porcelain under the worst contamination level. This test is available, entitled;
Compositz Insulators are truly versatile in that they may be used as line-post, station post, fuse dropout, V-string, crossarm, guy, and suspension/ tension insulators. Insulation ratings vary from 6kV up to 800kV depending on the length of insulator.
Because of their light weight, several Compositz Insulators can be carried up a pole at one time, and should more be required then only a light string line is necessary to haul them up.
There is no need to pre-assemble insulators on the ground, such as with disc insulators.
Standard hardware is supplied with each Compositz Insulator, such as clevis pins or socket security clips. In a tension application, a RELIABLE Automatic Dead-end with integral clevis pin (and/or pulling eye) may be attached directly to the tongue of a "tongue and clevis" insulator. Alternatively a standard clevis thimble and helical dead-end may be used.
Instructional material, especially with the use of Computer Assisted Learning (CAL) CD-ROMs, is suited to Compositz Insulators because all training can be developed with the assistance of the Energy Australia Distribution Support Branch.
Compositz Insulators are designed to provide cost effective solutions for the unique as well as the everyday applications. The variety of strength ratings available enables one to select the best insulator for a given application by using higher strength where required, and reducing cost when the strength is adequate.
The electrical performance of Compositz is unequalled by alternative products when compared under normal and extreme operating conditions. The light weight, vandal and breakage resistance, immunity to carbonised tracking, superior ultraviolet radiation performance and corona and RIV performance make Compositz the best choice for all applications.
Electrical and Mechanical performances and suitability of materials with regards to Erosion, Corrosion, Pollution, Durability and Stability.
The suitability of silicone rubber with respect to erosion, corrosion, pollution, durability and stability are available in the attachments:
The highlight of these presentations is that the silicone-oxygen atomic bond is stronger than ultra violet radiation and stronger than the carbon-carbon bond.
All end fittings are made of high strength ductile iron or forged steel and are galvanised to ASTM standards to resist corrosion. End fitting shapes are custom designed for high voltage applications. A unique arc control lip serves as a sacrificial surface for power arcs that may be caused by overvoltage surges. This lip also reduces electrical stresses that generate corona. Compositz end fittings are designed to protect both the fibreglass resin strength member and its silicone rubber protective coating. End fittings are sealed in place by a flexible silicone rubber sealant as a final barrier to moisture entry. A variety of end fittings are available to meet every line application, socket, ball, corona ball, eye, clevis, tongue, and y-clevis.
The mechanical load bearing element of all Compositz Insulators is a pultruded fibreglass reinforced resin rod. Because a composite insulator is only as strong as its core rod, Reliable selects only those rod materials and manufacturing processes which can provide high mechanical strength under dynamic loading conditions. Each core rod must meet stringent quality control standards for dielectric strength, glass content, and moisture absorption which ensure long consistent service life.
The long term reliability of Compositz Insulators is outlined in the paper:
"Application of Composite Insulators Using the Standard Deviation of Electrical Impulse Tests to Meet Basic Insulation Level Requirements"
Quality assurance testing is performed throughout the manufacture of Compositz Insulators beginning with the inspection of incoming raw materials. Silicone rubber is tested for tensile strength, elongation, tear strength, hardness, arc resistance, density, HV diffusion resistance, and track resist-ance. The fibreglass resin rod is tested for viscosity, optical control, dimensions, cure time, glass concentration, electrical puncture, interlaminar shear, and tension. End fittings receive both raw and machined dimensional checks, sectioning, galvanising thickness, tensile strength, and porosity tests.
The entire manufacturing process of Compositz Insulators meets the requirements of ISO 9002 for Quality Assurance. Not only are incoming raw materials thoroughly tested for high quality but the finished product under-goes rigorous testing as well. Each completed insulator passes a proof test of mechanical strength. This routine test load is applied for 15 seconds at ambient temperatures, guaranteeing the insulator will perform at its design load rating.
Further to the information contained in the training media, it should be pointed out that Compositz Insulators require no washing either before or during service.
Whilst the insulators can be dropped from the height of a pole or transmission structure, the insulator should be checked visually before re-use. Also be aware that the insulators may bounce and disrupt other equipment or personnel.
Spare parts are available at Dulhunty Industries should connecting hardware be lost or misplaced. Compositz Insulators are warranted against failure for twelve months from the date of delivery.
Further Documentation
Further documentation is available as per the Marketing Aids list.
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a composite insulator in the lower half.
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