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| Copper or Aluminium Rods | ||
| Wire Drawing | Wires are drawn for required size. | |
| Annealing | Drawn Copper/Aluminium wires are annealed. | |
| Stranding | Required conductor size is manufactured with specific design i.e. Shaped/Round. | |
| Insulation | Conductors are insulated with PVC/XLPE as per required specification to make Core. | |
| Pairing & Screening | Two core care twisted to make a Pair. These are screened with Polyester, Aluminium Mylar and drain wire. (for Screened Cables only). | |
| Core Rewinding & Curing | Cores to be rewound & Cured with specified requirements (for XLPE Cables only). | |
| Laying Up | All rewound Cores to be laid together to form a cable with specified design. | |
| Overall Screening | The cable is screened with Polyester, Aluminium Mylar and drain wire (for Screened Cables only). | |
| Inner Sheathing | Is done with reequired specification either with Tape or Extrusion. | |
| Armouring | Is done with required specification with trip/wire. | |
| Outer Sheath | Is done by Extrusion with specified type of PVC as per specification. | |
| Rewinding & Testing | All cables are rewound on Wooden Drums & Tests are carried-out as per specification. | |
| Packing | All tested and passed cables are packed in required sized drums prior to despatch. | |
Manufactuing of Cables
Cables with Aluminium and Copper conductor and polymer insulation are
manufactured at Works at Delhi and Bhiwadi. Essentially cables comprise
of conductors, insulation, innersheath, armour and outersheath.
| Conductor | |
| • | Rallison Cables are avialable with both aluminium
and copper conductor. |
| • | Rallison Cables are manufactured with solid/
stranded circular/ shaped Aluminium/ Copper conductor. |
| • | Stranding makes Cables flexible and easy
to handle while shaping makes them compact. |
Compaction is provided to all stranded conductor constructions as under:
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Circular Conductor: With one wire in the center conductor contains 6,12,18,24,30...... wire layers in either unilay or opposite helical directions. The conductor is Compacted.
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Shaped Conductor: In all multicore cables from 16 Sq.mm. size, conductors are "Shaped". However 6 & 10 Sq.mm. conductor can be solid/stranded circular.
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Segmental Conductor: As a special case Rallison cables of 1600 Sq.mm. are made up of segmental conductors.
Rallison Copper conductor cables are of the same construction that of cables with Aluminium conductor except for high tensile strength, superior conductivity, better flexibility and ease of jointing, Copper cables are used in control, instrumentation, winding, submarine, mining and ship wiring etc. applications.
All conductors for Rallison Cables are manufactured strictly in accordance with National and International specification.
National specifications - IS:8130
International specifications - IEC:60228/ BS:6360
Insulation
Insulation for Rallison Cables is strictly as per National and International
specifications. Rallison cables are designed and manufactured with polymer
dielectrics to bear thermal and thermomechanical stresses safely at
continuous normal and short circuit temperature conditions.
Rallison cables are available with both thermoplatic & thermo setting insulations.
PVC Cables - Thermoplastic dielectric
XLPE Cables - Thermo setting dielectric
Rallison PVC Cables use PVC Compounds that take care of over load and short current with both course & fine protection systems.
Rallison XLPE cables use XLPE Compound with antiu-oxidant stablizers and traces of aromatic polunuclear hydrocarbon. Thus improving electrical treeing characteristics and mechanical strength of insulation.
Pair Screening
Two core are twisted to make a Pair. A tape of Polyester is applied
over the Pair and then another tape of Aluminium Mylar is applied alongwith
Drain wire.
Laying Up
Cores are tested on line during production both for physical and electrical
characteristics. Control is observed within tight tolerance limits for
dimensions in case of PVC/XLPE insulation.
Overall Screening
A tape of Polyester is applied over the laid up pairs and then Aluminium
Mylar is applied along the Drain wire.
Inner Sheath
Laid up cables are provided with innersheath of Tape/Extruded PVC with
high quality of PVC which acts as bedding for steel wire/strip armouring
and circularity is maintained.
In Rallison cables- polymer used for innersheath are softer than insulation or outersheath & are compatible with temperature ratings of cables & do not have deleteriocus effects on any other component of cable.
The innersheath dimensions are maintained strictly in accordance with laid down specification.
Specification
For PVC Cables - IS:1554 (Part-I)
For XLPE Cables - IS: 7098 (Part-I)
Armouring
Mechanical protection to the cable is provided with armouring. Rallison
single core cables are armoured with Aluminium or Aluminium wire/strips,
thus avoiding magnetic hysteresis losses on A.C. system.
Multicore cables are provided with galvanized steel wire/strips. Rallison cables are provided with galvanized wire armouring, where cables are to run vertically and are subject to strsses.
Rallison Mining Cables are armoured with double steel wire and tinned copper wires, so as to provide conductivity of armour more than 75% of main conductor of cable.
Rallison cables armour wire/strips are of low resistivity material and meet the requirements of IS: 3975.
Outersheath
All Rallison cables are provided with PVC/HR PVC/FR/FRLS outersheath.
Rallison cables are manufactured with various characteristics of sheathing compounds.
| General purpose sheathing copound | ST-1 | |
| Heat resistant Compound for sheath (H.R.) | ST-2 | |
| Fire Retardant Low Smoke Compound (FRLS) | IEC 754 Part I IEC 60332 Part I & II IEEE- 383 ASTM- 2843 ASTM- 2863 |
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| Flame Retardant Compound (FR) | to EIL Specn. | |
Ultra Violet Radiatoins
Resistance Compound to ASTM G-53 |
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Anti Rodent and Anti
Termite Compound is applied where the customer ask for it. |
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PVC Compounds used
for Rallison cables are of various grades to meet specifications
IS: 5831. |
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In order to be identified, Rallison cables have their names embossed/printed/intended on outersheath at regular intervals.
ON the outersheath of Rallison cables. Voltage grade, Cable size, Trade Name & year of manufacture are embossed, as desired by the customer.
Cables are sequentially marked for length at every metre throughout its length.
Final Testing
Each Rallison Cable is tested for all applicable Routine Tests. From
a lot of Cable one cable of each type is tested for Type Tests, as per
relevant specifications.
Rallison conduct its testing at Rollex Electroproducts (P) Ltd. cable plant at Delhi for acceptance test as per specification.
Testing of Rallison Cables are carried out as per Rallison work standards for testing, besides applicable standards.
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