QUALITY ASSURANCE PLAN.

 We have a vigorous Quality Manual Plan comprising testing of incoming material, in line checks during production and final testing. The quality manual program is regularly reviewed to upgrade it.

 Our laboratory is equipped with all the instruments to ensure that the various tests required under different specification are conducted before cables are cleared for dispatch. Each consignment of cables is dispatched to the customer with test report results of tests conducted in our laboratory. The details of tests conducted on raw material, in process and on final stage are given below:-

 TEST ON RAW MATERIALS

Raw materials are procured from approved vendors. Testing on raw material starts from vendor's end. The raw material are received along with the vendor's test report. The following tests conducted to test the raw material/verify the vendor's test report. 

  1. Conductor:-

 Tests are conducted on conductor as per IS: 8130:1984. Apart from these tests, if customers requires any other additional test. Those tests are also conducted.

  1. P.V.C. Compound.

 

Tests are conducted on PVC Compound are as per----------------. Apart from these tests, if customers requires any other additional tests. Those tests are also conducted.

Sample of every consignment is first run on trial basis and following tests are conducted: -

 

i)

Insulation Resistance

:

With Mega Ohms Meter.

ii)

Elongation

:

With Tensile Testing Machine.

iii)

Tensile Strength

:

With Tensile Testing Machine.

iv)

Spark Testing

:

With on line Spark Testers.

v)

High Voltage Test

:

With High Voltage Tester.

vi)

Thermal Stability Test

:

With Oven & PH Paper.

 

IN PROCESS TESTING

 

 

PROCESS

 

TESTS

a)

CONDUCTOR STRANDING

1.

Dimension of Conductor.

 

 

2.

Lay Length & Direction of Lay.

 

 

3.

Surface and Shape of Conductor

 

 

4.

D.C. Resistance.

b)

INSULATION

1.

Dimension of Core.

 

[PVC EXTRUSION]

2.

Insulation Thickness.

 

 

3.

Eccentricity of Insulation Wall.

 

 

4.

Spark Test.

c)

LAYING OF CORES.

1.

Sequence of Cores.

 

 

2.

Lay Length & Direction of Lay.

 

 

3.

Laid Up Diameter.

 

 

4.

Circularity of Cable.

 

 

5.

High Voltage Test.

 

 

6.

Conductor Resistance Test.

d)

INNER SHEATH

1.

Surface.

 

[PVC EXTRUSION]

2.

Concentricity.

 

 

3.

Thickness.

 

 

4.

Diameter Over Inner Sheath.

 

 

5.

High Voltage Test.

 

 

6.

Conductor Resistance Test.

e)

ARMOURING

1.

Number & Size of  Wire/Strip.

 

 

2.

Lay Length & Direction of Lay.

 

 

3.

Dia. Over Armouring.

 

 

4.

Uniformity & Circularity of Cable.

 

 

5.

High Voltage Test.

 

 

6.

Conductor Resistance Test.

f)

OUTER SHEATH

1.

Surface.

 

[PVC EXTRUSION]

2.

Concentricity.

 

 

3.

Thickness.

 

 

4.

Overall Diameter.

 

 

5

Embossing/stamping with requisite Information  on outer sheath.

 

 

All the cables drums leaving "Merit Cables®" works undergo the following tests at final stage of manufacturer:

ROUTINE TESTS 

  1. Conductor Resistance Test
  2. High Voltage Test.

 

ACCEPTANCE   TESTS

  1. Conductor Resistance Test
  2. Annealing Test [For Copper]
  3. Tensile strength Test [For Aluminium]
  4. Wrapping Test [For Aluminium]
  5. Thickness of Insulation, Inner sheath & Outer Sheath.
  6. Tensile Strength & Elongation Test of Insulation & Outer Sheath.
  7. Insulation Resistance Test.
  8. High Voltage Test at Room Temperature Test.

 

Cable Design & Construction

Armoured and Unarmoured Single Core, Twin Core, Three Core and Multicore Copper or Aluminium conductor PVC Insulated & Sheathed cables for Electric supply and control purposes for use on AC voltage upto & including 1100 V or DC upto & including 1500 V to earth.

 Conductor:

The most acceptable metals for conductors are Copper or Aluminium due to their high conductivity and ductility. Therefore, Conductor material normally employed in PVC Cables are O, H2, or H4 EC grade Aluminium or high conductivity annealed copper or annealed tinned copper conforming in all respect to---------------------.

 

As Copper gets higher affinity with Sulphur, it corrodes in the atmostphere where Sulphur fumes are present. In these conditions, tinned copper shall be used. Power Cables are mostly manufactured with Aluminium .Use of Copper has been restricted to Control Cables, Signalling Cables and Mining Cables as per Govt. Directives.

  

The most economic construction for conductor is solid conductor. As area of conductor increases, solid conductor becomes more stiff and hence difficult to handle. In this connection Stranded Construction is adopted i.e.made of number of strands, arranged in spiral layers in 1+6+12+18+24......formations.

Shaping of conductor is necessary in making Multicore Cables sizes above 10.0 Sq.mm. In aluminium & 6.0 mm in copper conductor to obtain compact and economic design. Here, Stranded Conductors are shaped into a segment of a circle so that when all cores are laid , they form a complete circle.

 

Insulation:

The PVC covering over conductor is called "INSULATION". It is a specially formulated best quality, high grade of Poly Vinyl Chloride conforming to --------------- and is applied by Extrusion process only. It is resistant to moisure, oils, alkalies, good dielectric and having high Insulation Resistance values, Fire Retarding, Permanent Colors