PVC cables

The amount of plasticizer added to the polymer in question varies, depending on the magnitude of the effect required. For example, a small addition of plasticizer may be made simply to improve the workabiUty of the polymer melt. This contrasts with larger additions made with the specific intention of completely transforming the properties of the product. For example, PVC without a plasticizer, ie, unplasticized PVC (PVC-U), is used in appHcations such as pipes and window profiles with plasticizer added, articles such as PVC food film, PVC cable insulation, and sheathing and PVC floorings are formed. 

This plays an important role and requires utmost care. While termination of LT PVC cables is easier with the help of a crimping tool, HT cables need a proper kit for jointing and end termination. The jointing material is also manufactured by the cable manufacturers. We are not providing details of these kits and their jointing procedures. These can be obtained from manufacturers catalogues. 

Another example is the influence of the electrical resistance of PVC cable insulation. This is caused not by the organic pigment itself but by ethoxylated surfactants, which are added as auxiliaries in the manufacture of these pigments, especially azo pigments. Contrary to a repeatedly expressed view, a possible electrolyte content, which laked azo pigments for example can have, has no effect on the dielectric properties of PVC [34]. Some pigment manufacturers offer special product ranges with verified dielectric properties for this purpose. 

Pigment preparations are frequently used in the PVC cable industry for coloration. The pigment content is often selected in such a way that one part by weight of the preparation is used to color 100 parts by weight of the polymer compound. The shades and color codes for cables and insulated lines are specified in standards in various European countries [35],... 

P.Y.17 may be used for mass coloration and also to print PVC film. For these purposes, P.Y.17 is frequently prepared on a VC/VAc (vinyl chloride/vinyl acetate) mixed polymer basis. Good dispersibility in plastics makes these preparations suitable even for thin films. The dielectrical properties of P.Y.17 allow its application in PVC cable insulations. 

P.R.41 is also known as pyrazolone red. It has lost most of its commercial importance in recent years. P.R.41 production is now limited to the USA, where it is mostly employed to lend color to rubber. To a lesser extent, P.R.41 is found in PVC excellent dielectrical properties make it a suitable candidate for PVC cable insulations. The pigment provides a medium to bluish red of limited brilliance, it is much bluer than P.R.38. P.R.41 is somewhat less fast than P.R.38, which is also true for its stability to a variety of organic solvents. However, it parallels P.R.38 in its alkali and acid resistance. P.R.41 is very lightfast in rubber 1% pigment concentrations equal step 6-7 on the Blue Scale, which meets practically any require-... 

P.R.48 4 does not bloom in plasticized PVC and is almost completely fast to bleeding. Its tinctorial strength in this medium is equally good. Desirable dielectric properties make P.R.48 4 a suitable candidate for use in PVC cable insulations. The pigment is also used for mass colored secondary acetate threads, fibers, and films wherever it meets the requirements for application. 

Good dielectrical properties make it a suitable candidate for PVC cable insulations. 

T (482°F) for failure of standard Polyvinyl Chloride (PVC) cable. 

Combustion products can affect sensitive electronic equipment. For example, hydrogen chloride (HCI) is formed by the combustion of PVC cables. Corrosion due to combusted PVC cable can be a substantial problem. This may result in increased contact resistance of electronic components. Condensed acids may result in the formation of electrolytic cells on surfaces. Certain wire and cable insulation, particularly silicone rubber, can be degraded on exposure to HCI. A methodology for classifying contamination levels and ease of restoration is presented in the SFPE Handbook... 

The first is metakaolin. This is a partially calcined product that forms above about 500 °C. Only about 10% of the original hydroxyl groups of the kaohnite are retained and much of the crystalline nature of the structure is destroyed. Metakaolin is considerably more reactive than the original kaolin and appears to have an especially reactive surface. It is generally used uncoated and finds most use in plasticised PVC cable insulation, where it is reported as giving uniquely useful electrical properties [86]. 

PVC Cable sheets (e.g., wire and cables, floor mats, industrial sheets) ... 

Use of Crosslinked VC/PE Graft Copolymers for Cable Insulation. At high temperatures, plasticized PVC cable insulations show a rather high flow. This should be improved by crosslinking of the thermoplastic insulation material. Unfortunately, PVC is not easily cross-linkable by chemical agents. The presence of about 503 of grafted or... 

Briggs, C.C., Bhardwaj, B., and Gilbert, M., Flame retardant PVC cable compounds using huntite-hydromagnesite, Paper 9.51, Proceedings of 5th BPF International Fillers Conference, May 19-20, Manchester, U.K., 1992. 

Ethylene copolymers (high molecular weight flexibilisers) have been proposed to replace liquid plasticiser for low smoke FR PVC cable formulations (238). 

Oparex 15 calcined calcium sulphate (Yesos Ibericos) was evaluated as a filler in plasticised PVC cable insulation compounds in comparison with two grades of calcium carbonate. Improvements were observed in tensile, electrical and low temperature properties, flammability and heat ageing characteristics and chemical resistance for calcium sulphate filled compounds, while no significant differences in water absorption and hydrolysis were noted. Studies of rheological properties showed improved processability in mixing and extrusion trials. URALITA... 

An attempt is made to contribute to the objective analysis of the role of PVC cabling in major fires such as that at Dusseldorf airport. Questions regarding smoke and toxic combustion gas evolved by PVC cable materials have repeatedly been posed. Today, functional fillers such as aluminium hydroxide (ATH) and magnesium hydroxide (MDH) are available to optimise PVC formulations, creating extremely low smoke and much less toxic gases. The latest research developments are illustrated using... 

Process performance and commercial status. The Akzo process was investigated on a pilot scale (30 kg/h) with PVC cable and pipe scrap. Some tests with mixed PVC waste were carried out on a larger scale (300 kg/h) with the support of the European Council of Vinyl Manufacturers, giving promising results. At the moment the project is on hold, even though there is a plan to realize an industrial-scale plant, with a capacity of about 50000 t/yr. On the other hand, Akzo Nobel has stopped all activities on HCl recycling from PVC [50]. The process is still at pilot-scale status, so that large uncertainty exists about its technical, enviromnental and economic performance. 

Low modulus polyester resin mortars have also been developed. They too cure rapidly. They are principally used to fill cable slots cut across asphalt runways and also to fill over PVC cable ducts installed in concrete runways and taxiways (Shaw, 1993b). 

Sicovinyl . [BASF AG] Organic and inorganic pigment cones, in plasticized PVC for mass coloring of plasticized PVC, PVC cable sheathing. 

The influence of moisture on the dielectric properties of three experimental resin casting systems and an epoxy based laminate is investigated in this chapter to see if the mechanisms described above, can be recognised. Besides, the resistivity of an epoxy based tank coating and that of plasticised PVC cable insulation material in contact with water is described. 

The Ki-value determination of PVC cable compounds The specific volume resistivity is the most important electrical property of an electrical grade PVC. It is measured on a heavily plasticised product, the cable compound, pressed to a 2 mm. thick sample sheet. Cable manufactures usually test the resistivity of these compounds on cable samples and express the results in a so-called Ki-value. The Ki-value is in fact a volume resistivity value (see below) but measured on a cable sample with tapwater as low potential measuring electrode. A series of Ki-value determinations was performed to investigate the different parameters influencing this quantity. 

The Ki value of a PVC cable compound as a function of the electrification time... 

A 6600 volt induction motor is fed from a fuse-contactor starter. Find the most appropriate fuse rating and the appropriate size of a PVC cable for the motor. The following data are known -... 

Pt characteristics can be found by using a k value of 110 for PVC cables with copper conductors. 

The secondary cable runs on its own cable rack to a switchboard. Both cable routes are short enough to neglect volt-drop considerations. Find suitable Cu/XLPE/PVC/SWA/PVC cable conductor sizes. 

Trimellitates are the esters of trimellitic anhydride (1,2,4-benzenetricarboxy-lic acid anhydride) and are noted for their low volatility. The most frequently used are trioctyl trimellitate (TOTM) and tri-isononyl trimellitate (TINTM). They are included in plastics which have to function at high temperatures for long periods and for PVC cable insulation in combination with phthalates. Phosphorous oxychloride reacts with various aliphatic and aromatic alcohols and phenols (triphenylphosphate) to produce triesters. Tricresyl phosphate was patented as a plasticizer for PVC in 1933, but was later found to be highly toxic and replaced. In addition to their role as plasticizers, phosphate esters, particularly triphenyl phosphate, function as flame retardants. 

PVC does not burn. In a fire, PVC cables form hydrogen chloride fumes as the major degradation product. The fumes scavenge free radicals thereby preventing the plastic burning. ... 

Addition of PTFE powder improves all parameters characterizing burning behavior of PVC cable eompound. 

Residual monomers or residues from polymerization may be harmful to health (e.g., vinyl chloride from PVC) or alter technical properties, for example residues of emulsifiers that reduce the insulating quality of PVC cabling. Solvent residues (diesel oil, toluene, etc.) from precipitation polymerization migrate over a period of years following implantation, albeit in the microgram range, from joint endoprostheses such as hip acetabula into body tissues. 

Chem. Descrip. Calcium carbonate coated by org. media CAS 471-34-1 EINECS/ELINCS 207-439-9 Uses Eiller in plastics (rigid PVC, cables, calendered sheets, moldings, polyolefins, wh. masterbatches), paints (gloss enamels), elastomers Features Completely compat. with organic media easily dispersed Properties Wh. rhombohedral ctyst. fineness 57% < 2 p dens. 2.7 g/ cm bulk dens. 1.1 g/cm (packed) oil absorp. 15/100 g powd. brightness 97.5% ref. index 1.59 pH 9 hardness (Mohs) 3 Microblanc TMB [Microfill K. Zafranas]... 

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