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LFX™ Graphite Electrode Solutions

LFX™ Graphite Electrodes

Grade LFX™ graphite electrodes offer the ladle furnace operator a strong, dependable electrode designed specifically for the ladle furnace. Every aspect was engineered to provide just the right characteristics for the demands of the application.

Application & Specifications

Today’s ladle furnaces’ operating parameters are different than melting furnaces. The application is not as demanding as UHP furnaces, but more than a low power electrode can handle.

U.S. Standard Lengths and Weights

Nominal Electrode Diameter (Inches)Standard Lengths* (Inches)Typical Weight of PRE-CET™ Electrode** (Pounds)Recommended Tightening Torques (Ft. Lbs.)
1060; 72310; 350300
1272510450
1472690600
1672; 84; 96900; 1010; 1220800
1872; 84; 961130; 1360; 15501000

*Typical range, property values not guaranteed.

Metric Units Lengths and Weights

Nominal Electrode Diameter (Millimeters)Standard Lengths* (Millimeters)Typical Weight of PRE-CET™ Electrode** (Kilograms)Recommended Tightening Torques (Nm)
2501500; 1800140; 160390
3001800230590
3501800310830
4001800; 2100; 2400410; 460; 5501075
4501800; 2100; 2400510; 620; 7001375

*Typical range, property values not guaranteed.

Footnotes to Tables:

*Non-Standard lengths may be available on a made-to-order basis.

**Indicates typical AGX™ electrodes combined weights of Electrode and Connecting Pin. Weights of AGR™ electrodes are approximately 5% lower.

Your GrafTech representative is happy to discuss how each of the above combinations affect your electrode selection. Please choose the Sales Office nearest you.

UCAR® Grade LFX™ Graphite Electrodes for Ladle Furnace Applications

US Standard Units

LFX®
ElectrodesUnits of Measure250 – 350400 – 450Method of Measurement
Bulk Densityt/m31.67 – 1.731.66 – 1.72ASTM C559
Specific ResistanceµOhm.m5.5 – 6.05.2 – 5.8ASTM C611
Flexural StrengthMPa10.0 – 13.09.0 – 12.0Four Point ASTM C651
Young’s ModulusGPa9.0 – 11.08.0 – 9.5ASTM C747
Coefficient of Thermal Expansioncm/cm/º10-6(30 to 100ºC)0.4 – 0.60.4 – 0.6PATE Machine/UCAR® Method
Porosity%20 – 2221 – 23Calculation:100(RD-BD)/RD
Thermal ConductivityW/mºC210 – 230220 – 240Calculation: 1.3 10-3/Resistivity
Nipples for LFX™ ElectrodesLFXASTM C747
Bulk Densityt/m31.76 – 1.82
Specific ResistanceµOhm.m3.6 – 4.3
Tensile StrengthMPa15.0 – 21.0
Young’s ModulusGPa12.0 – 16.0
Thermal Conductivitycm/cm/º10<sup>-6</sup>(30 to 100ºC)0.1 – 0.3

*Typical range, property values not guaranteed.

Mean CTE:

Final Temperature Degrees CelciusAdded factor
1000
2002.0 x 10-7
3004.0
4006.0
5007.7
6009.2
70010.4
80011.4
90012.3
100013.2
150017.2
200021.2
250025.2

*Typical range, property values not guaranteed.

Definitions:

Bulk Density – A measurement of weight per unit volume. A higher bulk density will generally be reflected in improved mechanical properties.

Flexural Strength – A measurement of stress required to cause rupture in bending. (Also called Bending Strength or Modulus of Rupture). Higher flexural strength in electrodes will generally result in lower electrode breakage frequency.

Note: As graphite is a brittle material, GrafTech employs the ASTM 4-Point loading method for strength-testing. This method yields test values about 25% lower than those obtained by the 3-Point loading method.

Tensile Strength – A measurement of pure tensile force per unit area required to cause rupture by pulling apart. Higher tensile strength in nipples will generally result in lower nipple breakage frequency.

Graphite’s strength characteristics increase significantly with increasing temperature.

Coefficient of Thermal Expansion (CTE) – A measurement of the increase in length per unit length per degree rise in temperature. Lower CTE will generally give better resistance to thermal shock. Also, CTE compatibility between the graphite electrode and connecting nipple is important for satisfactory performance of the electrode joint.

The change in CTE with temperature is about the same for all graphite at high temperature. The mean linear CTE between room temperature and any final temperature can be obtained using the factors shown below.

Specific Resistance – A measurement of opposition to electric current flow. Low specific resistance of graphite electrodes allows maximum current carrying capability without overheating of the electrode column. The chart below shows the effect of temperature on the relative electrical resistivity of graphite electrodes.

relresist

Footnotes to Tables:

*Typical range property values not guaranteed.

*Electrodes and nipples are extruded products. Thus, these tables show only typical values which may vary from size to size, piece to piece or even within a piece.

UCAR® Graphite Electrodes and connecting nipples meet dimensional tolerances by IEC, JIS and NEMA as required by customers worldwide. Norms are available on request.

Ash Content: UCAR® Graphite Electrodes typically have less than 0.1% impurities and do not contain elements harmful to steelmaking.

LFX™ Grade Graphite Electrode Combinations

U.S. Standard Units

Electrode Diameter (Inches)IEC DesignationPin Dimensions (Inches)Threads per 25.4 mm
10152T4N6 x 7.54
10155T3N6.125 x 8.663
12155T3N6.125 x 8.663
12177T3N6.975 x 10.663
12177T4N7 x 8.54
14177T3N6.975 x 10.663
14203T4N8 x 104
14203T4L8 x 124
14215T3N8.5 x 123
16215T3N8.5 x 123
16222T4N8.75 x124
16222T4L8.75 x 144
16241T3N9.5 x 13.333
16241T3L9.5 x 143
18241T3N9.5 x 13.333
18241T3L9.5 x 143
18241T4L9.5 x 144
18269T4L10.625 x 184
18273T3L10.75 x 183

*Typical range, property values not guaranteed.

Metric Units

Electrode Diameter (mm)IEC DesignationPin Dimensions (mm)Threads per 25.4 mm
250152T4N152.40 x 190.504
250155T3N155.57 x 220.003
300155T3N155.57 x 220.003
300177T3N177.16 x 270.903
300177T4N177.80 x 215.904
350177T3N177.16 x 270.903
350203T4N203.20 x 254.004
350203T4L203.20 x 304.804
350215T3N215.90 x 304.803
400215T3N215.90 x 304.803
400222T4N222.25 x 304.804
400222T4L222.25 x 355.604
400241T3N241.30 x 338.703
400241T3L241.30 x 355.603
450241T3N241.30 x 338.703
450241T3L241.30 x 355.603
450241T4L241.30 x 355.604
450269T4L269.88 x 457.204
450273T3L273.05 x 457.203

*Typical range, property values not guaranteed.

Footnotes to Tables:

*Other pin sizes and may be available on a made-to-order basis.

Click here, for UCAR® Graphite Electrode Standard Lengths and Weights.

UCAR® Graphite Electrodes and connecting pins meet dimensional tolerances set forth by IEC, JIS, and NEMA as required by customers worldwide.

Your GrafTech representative is happy to discuss how each of the above combinations affect your electrode selection. Please choose the Sales Office nearest you.