U. S. Steel returns Gary Works Furnace 14 to service

U. S. Steel completes a $350 million reline at Gary Works, returning its largest blast furnace to service after refractory and infrastructure maintenance.

Blast Furnace 14 returns to service

U. S. Steel has returned Blast Furnace 14 at Gary Works in Indiana to operation after a $350 million reline. The project replaced the furnace’s refractory lining and restored critical systems to support its continued operation. The furnace is the largest in the company’s operating footprint.

Blast Furnace 14 can produce more than two million tons of hot metal annually. This is an ironmaking-capacity measure, rather than a figure for finished steel production. The company’s Minnesota Ore Operations supply iron ore pellets for the furnace as part of its domestic production chain.

Carbon refractory blocks in a maintenance workshop — Blast-furnace refractory maintenance

Relining and supporting infrastructure

The furnace outage ran from February to September 2026. U. S. Steel began the reline months after Japan-based Nippon Steel completed its acquisition of the company. The project involved maintenance beyond the refractory replacement. Teams worked on furnace-gas, cooling-water, hoisting and stove systems during the outage. The maintenance programme covered supporting infrastructure used in the furnace’s operation, alongside the principal relining work.

Employees and contractors contributed more than one million labour hours. The company reported a peak workforce of approximately 1,000 contractors on site per day. Those figures describe the construction and maintenance effort; they are not an announcement of 1,000 newly created permanent operating jobs.

Safety and continued Gary Works investment

U. S. Steel reported a Zero Days Away Injury Rate for the project. This is the company’s stated measure for the work performed and should retain its precise name. It does not establish that no incident of any kind occurred during the outage.

President and chief executive David B. Burritt credited employees, contractors and partners with completing the work. The company places the furnace investment alongside hot-strip-mill and related steel-shop upgrades at Gary Works, aimed at improving capability, environmental performance and operational reliability.

United States Steel company identity

The reline uses large carbon-block refractory produced by NDK. The company identifies the renewed furnace as an asset supporting long-term ironmaking at Gary Works. Its return to service is a completed project milestone, distinct from plans for future investment or an increase in the furnace’s stated annual capacity.

U. S. Steel was founded in 1901 and is headquartered in Pittsburgh, Pennsylvania. Its customer industries include automotive manufacturing, construction, appliances, energy, containers and packaging. Its production system includes iron ore operations, integrated steelmaking facilities and electric-arc-furnace investments.