Case Studies · Iron & Steel

EAF Delta High Emissivity Coating: Service Life Up 115% at an Integrated Steel Plant

Pre-cast electric-arc furnace deltas·Integrated steel plant

Pre-cast ultra-low-cement deltas near the arc and scrap charge were cracking early from thermal shock, lasting about 40 heats, and only 80 after an upgrade to a spinel-containing castable. Coating the hot faces and electrode ports with Emisshield ST-2 raised average life to 172 heats, a 115% improvement, by shielding the surface through the initial heats so the castable could sinter properly.

Talk with an Expert Case Study Library

172 heats average
: +115% vs upgraded refractory
: 1,560 to 1,650°C

The Challenge

Early cracking limited delta life and the plant wanted more longevity without redesigning the furnace.

What Was Applied

Emisshield ST-2 on the deltas' hot faces and electrode ports, operating between 1,560 and 1,650°C.

Why It Worked

The coated surface resists abrupt temperature spikes from arc flare during the first heats, the period when thermal shock does its damage, and re-radiates into the melt thereafter. See Production Increase, component life.

Summary of Results

Metric	Uncoated (upgraded castable)	Coated
Average delta life	80 heats (40 with original castable)	172 heats
Life increase		+115%
Early thermal-shock cracking	Recurring	Eliminated
Maintenance and replacement interval	Baseline	Reduced; extended

The coating let the spinel-containing castable develop full strength, maximizing the refractory investment.

Next step

Operating the Same Asset?

Replacing deltas or roofs on a short cycle? Send us the furnace data and heat counts. We project the result from comparable documented installations.

Talk with an Expert Request a Quote