Quality Check

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Quality Check

Excellence Through Stringent Standards.

Our commitment to excellence is evident through rigorous quality checks and audits from material procurement to packaging. We adapt to market dynamics, ensuring consistent delivery of high-quality products within set timelines for customer satisfaction.
  • IEC 60404-8-1
  • AISI M6-2006
  • ASTM A677
  • ASTM A876
  • NEMA TP 1
  • IS 3024
Quality Check Policy
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This commitment is upheld through the following initiatives:

  1. Continual enhancement of the effectiveness of our Quality Management Systems.
  2. Prudent allocation of resources to ensure controlled costs.
  3. Pioneering process innovations to elevate quality standards.
  4. Regular motivation of our workforce through diverse channels.
  5. Offering comprehensive support to clients for the seamless execution of their projects within specified timelines.

Raw Materials:

The final output quality is contingent upon the excellence of the input. At Vilas Transcore, we conduct thorough and pertinent quality checks on raw materials. Only those raw materials that successfully pass through rigorous quality tests are utilized in the manufacturing process.

Lamination:

Quality control checks for lamination are performed regularly throughout the manufacturing process on each machine, and a separate record is maintained. These checks encompass aspects such as edge, width, burr, camber, thickness, watt losses, stack factor, wave factor, and more.

Toroidal Cores / Wound Core:

The quality check includes assessing magnetic properties at specified flux density and dimensional measurements, including overall dimensions, inside diameter, and height.

Technical Details of CRGO:

Cold Rolled Grain Oriented Steel (CRGO) is available in various grades, commonly known as M3, M4, M5, and M6, adhering to major international standards such as Japanese (JIS), American (ASTM), German (DIN), and British standards. While conventional CRGO grades like M3, M4, M5, and M6 are regularly used for lamination cores in transformers, recent emphasis on environmental protection and energy savings has led to the development of low-loss Hi-B materials. Nippon Steel Corporation and other CRGO producing mills have introduced Hi-B materials, ensuring low watt losses at a flux density of 1.7 Tesla.

The table below illustrates the magnetic properties of Hi-B materials, with popular CRGO Hi-B grades being 23 MOH & 27 MOH ZDKH, ZDMH/HPDR.

Manufacturing mills of CRGO Steel guarantee the core loss figure at a flux density of 1.5 Tesla for conventional grain-oriented steel and at 1.7 Tesla for Hi-B Steel and Hi-B-LS Steel, emphasizing energy efficiency.

Flux Density V/s Losses

  • These results were measured in Vilas Transcore Limited Testing Laboratory.
  • These values are for reference only.
  • All values are in Watts/kg @ 50 Hz

Flux Density (Tesla)

23PHD85

27ZDKH90

27ZDKH95

23 MOH

27 MOH

30 MOH

M3

M4

M5

M6

1.30

0.46

0.51

0.48

0.53

0.57

0.57

0.49

0.64

0.68

0.73

1.35

0.49

0.55

0.51

0.57

0.60

0.62

0.53

0.68

0.74

0.79

1.40

0.53

0.59

0.57

0.61

0.66

0.65

0.58

0.74

0.80

0.86

1.45

0.57

0.63

0.61

0.66

0.70

0.70

0.64

0.78

0.87

0.94

1.46

0.58

0.64

0.62

0.67

0.71

0.71

0.65

0.80

0.88

0.97

1.48

0.60

0.66

0.64

0.66

0.73

0.74

0.67

0.82

0.91

1.03

1.50

0.61

0.67

0.66

0.70

0.74

0.76

0.70

0.84

0.94

1.11

1.52

0.63

0.69

0.68

0.72

0.76

0.78

0.72

0.88

0.97

1.14

1.54

0.65

0.71

0.70

0.74

0.79

0.80

0.75

0.90

1.01

1.18

1.56

0.67

0.73

0.72

0.76

0.81

0.83

0.78

0.93

1.04

1.22

1.58

0.69

0.75

0.74

0.78

0.83

0.85

0.81

0.96

1.08

1.26

1.60

0.71

0.77

0.76

0.80

0.85

0.87

0.85

1.00

1.12

1.30

1.62

0.73

0.79

0.79

0.83

0.89

0.90

0.89

1.03

1.16

1.35

1.64

0.75

0.81

0.83

0.85

0.91

0.93

0.93

1.07

1.20

1.40

1.66

0.78

0.84

0.87

0.88

0.94

0.96

0.98

1.10

1.25

1.45

1.68

0.81

0.87

0.91

0.93

0.96

1.00

1.03

1.15

1.30

1.51

1.70

0.84

0.90

0.95

0.95

1.00

1.05

1.09

1.20

1.36

1.57

1.72

0.86

0.93

1.01

0.98

1.02

1.07

1.15

1.24

1.42

1.64

 

Important Physical Properties of CRGO

Density gm/c3

7.65

Silicon content%

3.10

Resistivity micro Ohm-centimetre

48.00

Ultimate tensile Strength 00 to Rolling Direction Kg/mm2

32.60

Ultimate tensile Strength 900 to Rolling Direction Kg/mm2

38.20

Stacking factor % M4 (.27mm)

96.00

Stacking factor % M5 (.30mm)

96.50

Stacking factor % M6 (.35mm)

97.00

CRGO materials come either in the form of coils or sheets. Given below the details of CRGO dimensions and tolerances as per JIS C 3553.

 

Standard Tolerance – Cut to Size Lamination

Sr.No

Characteristics

Acceptance Limit/ Criteria

1

Width (mm)

0 to 100 (± 0.15)

100 to 130 (± 0.20)

230 to 380 (± 0.25)

380 to 580 (± 0.40)

580 to Above (± 0.50)

2

Thickness (mm)

± 0.03 mm

3

Edge Burrs (Micron)

 

Thickness (mm)

 

Up to 0.23

15

Up to 0.23

15

0.35

20

4

Length (mm)

Up to 350 (+0.00 / -0.30)

350 to 1000 (+0.00 / -0.60)

1000 to 2000 (+0.00 / -1.00)

2000 and Above (+0.00 / -2.00)

5

Edge Chamber

For the material with a width greater than 150 mm,
edge chamber shall not exceed 0.8 mm for a length 1.5 meter

6

Wave Factor
(i.e., Deviation from Flatness)

For a material of width greater than 150 mm the deviation from flatness expressed as a percentage shall not exceed 1.5%

7

Angel

± 5 Minutes

8

Stack Thickness of individual
stack except center step unclamped

+1 -0 mm

 

Testing Parameter for Toroidal Core

Reluctance – Toroidal Core

Grade of Material

AT 0.5 Tesla AT/CM

AT 1.0 Tesla AT/CM

AT 1.5 Tesla AT/CM

AT 1.7 Tesla AT/CM

0.23 ZDMH/HPDR

0.06

0.10

0.20

0.30

0.23 ZdKH

0.07

0.12

0.22

0.32

0.23 MoH

0.08

0.15

0.26

0.35

0.23 M3

0.09

0.18

0.30

0.45

M4

0.12

0.22

0.32

–

M5

0.15

0.28

0.40

–