30+ YEARS OF EXPERIENCE IN CARBON INDUSTRY

How Improper Electrode Pressing and Releasing Operations Lead to Electrode Paste Breakage

Electrode pressing and releasing essentially involves moving the cooled, sintered electrode section downwards to compensate for the continuous consumption of the lower electrode end within the furnace. It is a crucial operation for managing the electrode's working length and replenishing with new electrode paste. Improper operation can cause destructive stress on the electrode at this vulnerable point:

1. Excessive/Frequent Electrode Paste Releasing: Releasing too much electrode paste at once, with a large amount of cold, unsintered electrode paste suddenly entering the high-temperature zone, will rapidly generate a large amount of pitch fumes, causing a surge in internal pressure, leading to electrode shell rupture (explosion), or even soft breakage.

2. Excessive Electrode Paste Releasing Speed: Rapid pressing and releasing is a form of "impact load." This dynamic load concentrates stress at a single point in the sintering transition zone, rather than distributing it evenly across the entire area. The combined inertial and frictional forces at high speeds can easily cause the fragile paste-like structure to be "torn" or "sheared."

3. Delayed Electrode Paste Releasing: If the electrode working end is too short, a "deep insertion" operation is forced, worsening furnace conditions and increasing power consumption.

4. Immediately after electrode paste placement, apply full load: New electrode paste, not yet calcined, has extremely low strength and is prone to slippage or bending under strong arc and electromagnetic forces.

The proper electrode paste placement procedure should follow the principle of "small placements, frequent placements," with each placement involving a small amount at a high frequency. Sufficient "calcination time" is required after placement to allow the newly added electrode paste to fully sinter before further placement or increasing the current.