UHP GRAPHITE ELECTRODE

UHP graphite electrode is mainly used for ultra high power electric arc furnaces with the current density greater than 25 A/cm2. UHP graphite electrode is used for the recycling of steel in the electric arc furnace industry. Its main ingredient is high-value needle coke which is made from either petroleum or coal tar. Graphite electrodes are finished with a cylinder shape and machined with threaded areas at each end. In this way, the graphite electrodes can be assembled into an electrode column using electrode nipple.In order to meet the requirement of higher work efficiency and lower total cost, large capacity ultra-high power arc furnaces are becoming more and more popular. Because of this, UHP graphite electrodes with diameters of over 500 mm will dominate market.

Category:

Features


  • Withstand large currents, high discharge rate.
  • Good dimension stability, not easy to deform.
  • Resistant to cracking & spalling.
  • High resistance to oxidation and thermal shock.
  • High mechanical strength, low electrical resistance.
  • High machining accuracy, good surface finishing.

Application


  • Graphite electrodes are widely used for production of alloy steels, metal and other nonmetallic materials, etc.
  • DC electric arc furnace.
  • AC electric arc furnace.
  • Submerged arc furnace.
  • Ladle furnace.

Technical Specification of UHP Graphite Electrode


Dia.ResistanceDensityFlexure StrengthElastic ModulusAsh ContentCTECurrent LoadCurrent Density
(inch)(≤, µΩ·m)(≥, g/cm3)(≥, MPa)(≤, GPa)(≤, %)(100 °C – 600 °C)(A)(A/cm2)
(≤, 10-6/°C)
105.21.6710.5140.31.58100–1220020–30
125.21.710.5140.31.515000–2200020–30
145.21.710.5140.31.520000–3000020–30
165.21.710.5140.31.525000–4000019–30
185.21.710.5140.31.532000–4500019–27
205.21.711140.31.438000–5500018–27
225.21.7211140.31.442000–6600017–26
244.81.7211140.31.449000–7600017–26

Graphite Electrode Size & Tolerance


Diameter (mm)Length (mm)
Nominal DiameterActual DiameterNominal LengthToleranceShort Length
(inch)(mm)(max.)(min.)(rough spot)
102502562512481600/1800±100-275
123003073022991600/1800
143503573523491600/1800
164004094034001600/1800/2000/2200
184504604544511600/1800/2000/2200
205005115055021800/2000/2200/2400
225505625565531800/2000/2200/2400
246006136076042000/2200/2400/2700

Surface Quality


There should be less than two defects or holes on the electrode surface, the maximum size of which is mentioned in the below chart.
There should be no transverse crack on the electrode surface. For the longitudinal crack, the length should be less than 5% of the electrode circumference and the width should be 0.3 to 1.0 mm.
The width of black area on electrode surface should be less than 1/10 of the electrode circumference and the length should be less than 1/3 of the electrode.

SpecificationDefect DimensionNominal Diameter of Graphite Electrode (mm)
300–400450–600
Diameter (mm)20–4030–50
(< 20 mm should be negligible)(< 30 mm should be negligible)
Depth (mm)5–1010–15
(< 5 mm should be negligible)(< 10 mm should be negligible)