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Graphite electrodes and nipples
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Intended for arc steel, refining, ferroalloy and ore-smelting furnaces Graphite electrode of EG grade are used in steel, refining, ferroalloy and submerged-arc furnaces (RP)
| Technical characteristics | Units of measurements |
Typical values* | |||
| Diameter | mm | 75-150 | 200-350 | 400-600 | 700 |
| Bulk density | g/cm3 | 1.62 | 1.62 | 1.61 | 1.58 |
| Ash impurities | % | 0,3 | 0,3 | 0,3 | 0,3 |
| Specific electrical resistance | мµОhm·m | 7.0 | 7.5 | 8.0 | 8.5 |
| Thermal coefficient of linear expansion, х10-6 (20-520)0С |
1/0С | 2.4 | 2.4 | 2.4 | 2.5 |
| Flexural strength | МPа | 11 | 11 | 9 | 7 |
| Modulus of elasticity (Young`s) | GPa | 8 | 7 | 7 | 6.5 |
Graphite electrodes of EGP grade are used in high power (HP) steel furnaces and ladle furnaces (LF)
| Technical characteristics | Units of measurements |
Typical values* | ||
| Diameter | mm | 200-350 | 400-500 | |
| Bulk density | g/sm3 | 1.74 | 1.72 | |
| Ash impurities | % | 0.3 | 0.3 | |
| Specific electrical resistance | µОhm·m | 7.0 | 6.5 | |
| Thermal coefficient of linear expansion, х10-6 (20-520)0С |
1/0С | 2.5 | 2.5 | |
| Flexural strength | MPа | 16 | 14 | |
| Modulus of elasticity (Young`s) | GPа | 9 | 9 | |
Graphite electrodes of EGSP grade are used on ultra high power (UHP) electric arc furnaces and ladle furnaces(LF)
| Technical characteristics | Units of measurements |
Typical values* | |
| Diameter | mm | 350-450 | 500-600 |
| Bulk density | g/sm3 | 1.72 | 1.70 |
| Ash impurities | % | 0.2 | 0.2 |
| Specific electrical resistance | µОhm·m | 6.0 | 5.2 |
| Thermal coefficient of linear expansion, х10-6 (20-520)0С |
1/0С | 2.1 | 1.3 |
| Flexural strength | МPа | 14.5 | 12.5 |
| Modulus of elasticity (Young`s) | GPа | 10 | 11 |
Nipples for graphite electrode.
| Technical characteristics | Units of measurements |
Typical values* | |||
| Diameter | mm | 75-150 | 200-350 | 400-550 | 600-700 |
| Bulk density | g/sm3 | 1.73 | 1.76 | 1.80 | 1.81 |
| Ash impurities | % | 0.2 | 0.2 | 0.2 | 0.2 |
| Specific electrical resistance | µОhm·m | 5.0 | 4.5 | 4.2 | 4.0 |
| Thermal coefficient of linear expansion, х10-6 (20-520)0С |
1/0С | 2.2 | 1.1 | 1.1 | 1.1 |
| Flexural strength | МPа | 18 | 18 | 22 | 22 |
| Modulus of elasticity (Young`s) | GPа | - | 17 | 18 | 18 |
* - indicated values are given as average values of properties and they do not constitute specification.
Dimensions of graphite electrode.
| Nominal diameter, mm |
Usual diameter | Allowable values of diameter, mm | Nominal length, mm | ||
| mm | inches | Maximum | Minimum | ||
| 75 | 76 | 3 | 78 | 73 | 1000/1200/1500 |
| 100 | 102 | 4 | 103 | 98 | 1000/1200/1500 |
| 125 | 130 | 5 | 132 | 127 | 1000/1200/1500 |
| 150 | 152 | 6 | 154 | 149 | 1200/1500 |
| 175 | 178 | 7 | 179 | 174 | 1200/1500 |
| 200 | 203 | 8 | 205 | 200 | 1500/1800 |
| 225 | 229 | 9 | 230 | 225 | 1500/1800 |
| 250 | 254 | 10 | 256 | 251 | 1500/1800 |
| 300 | 305 | 11 | 307 | 302 | 1500/1800 |
| 350 | 356 | 12 | 357 | 352 | 1500/1800 |
| 400 | 406 | 16 | 409 | 403 | 1500/1800 |
| 450 | 457 | 18 | 460 | 454 | 1800/2100/2400 |
| 500 | 508 | 20 | 511 | 505 | 1800/2100/2400 |
| 500 | 508 | 20 | 511 | 505 | 1800/2100/2400 |
| 550 | 559 | 22 | 562 | 556 | 1800/2100/2400 |
| 600 | 610 | 24 | 613 | 607 | 2100/2400/2700 |
| 700 | 711 | 28 | 714 | 708 | 1800/2100/2400 |
Allowable deviations of graphite electrodes length .
| Nominal length, mm | Deviation of electrode length, mm | Deviation of short electrode length, mm | ||
| Maximum | Minimum | Maximum | Minimum | |
| 1000 | +50 | -75 | -75 | -200 |
| 1200 | +50 | -100 | -100 | -225 |
| 1500 | +50 | -100 | -100 | -275 |
| 1800 | +75 | -100 | -100 | -275 |
| 2100 | +75 | -125 | -125 | -275 |
| 2400 | +75 | -125 | -125 | -275 |
Recommended current loads during pefomance of graphite electrodes.
| Nominal diameter, mm | Limits of allowable current density, А/сm2 | ||
| EG | EGP | EGSP | |
| 150 | 18-25 | - | - |
| 200 | 18-25 | 20-30 | 25-35 |
| 250 | 15-20 | 20-25 | 25-35 |
| 300 | 15-20 | 20-25 | 25-35 |
| 350 | 15-20 | 20-25 | 25-35 |
| 400 | 15-18 | 18-22 | 25-30 |
| 450 | 15-18 | 18-22 | 25-30 |
| 500 | 15-18 | 18-22 | 22-28 |
| 550 | 15-18 | 18-22 | 22-28 |
| 600 | 10-15 | 15-20 | 22-28 |
| 700 | 12 | - | - |
Selection of a grade of graphite electrodes is carried out by experts of PJSC "Ukrgrafit" on the basis of operating conditions.
Chief expert in graphite electrodes zarochentsev@ukrgrafit.com.ua.