Wire & Cable Jacket Irradiation |
Energy level evaluation
Automotive wires (High Density Polyethylene compound p=1.3 g/cm³)
- 0.35 mm² (OD 1.4 mm / W 0.28 mm)
- keV = 197 * 1.3 {0.28(1.4 – 0.28)} ½ + 325
= 468 (400 keV if twisting)
- 6.00 mm² (OD 4.3 mm / W 0.45 mm)
- keV = 197 * 1.3 {0.28(4.3 – 0.45)} ½ + 325
= 660 (440 keV if twisting)
It is a common in the irradiation technology to consider that the energy level (MeV) is adequate when the energy deposition level inside the product is at least the same as the surface level.
Please note that a compound of higher density would require higher energy.
Equally, a thicker wall insulation would also require a higher energy.
- Power evaluation
Once the energy level is calculated, the power of the accelerator must be evaluated. Evidently, the more products you want to irradiate per unit of time, the higher the power required.
The capability (meters/minutes) of the E-Beam accelerator considered is evaluated in function of the constraints with the following formula;
m/min = 1549 * I / S * D
- I = Beam current (mA) ;
- S = Center line spacing of wires (mm), not less than 2*OD
- D = Dose (Mrad) - note : 1Mrad = 10 kGray
- D is set for each compound and mechanical property
Example
- 0.35 mm² (OD 1.4 mm / W 0.28 mm)
m/min = 1549 * 50 / 3.08 * 10
> 1,200 m/min
- 6.00 mm² (OD 4.3 mm / W 0.45 mm)
m/min = 1549 * 50 / 9.46 * 10
> 800 m/min
Irradiation :
Key Concept
