A DRI shaft furnace runs continuously for thousands of hours between planned stops, and an unplanned shutdown on either a MIDREX or HYL line can erase well over a hundred thousand dollars in lost production in a single day. The first sign is rarely dramatic: a reformer inlet temperature drifting slightly, a syngas compressor bearing running warmer, a gas recycling valve that's cycling a touch slower than before. This checklist covers the eight points a DRI plant inspection route should never skip. Sign up to turn this checklist into a recurring digital inspection your team can't miss a step on.
8 Points
Core checks that belong on every MIDREX and HYL inspection route
90%+
Typical H2 plus CO concentration the reducing gas needs to hold
8,000+ Hrs
Annual availability target a well-run DRI plant aims to achieve
Zero Skips
Tolerance for missed checks, since early drift rarely repeats itself
Why MIDREX And HYL Need Different Inspection Priorities
Both technologies share a shaft furnace core, but their reforming architecture is different. MIDREX uses an external catalytic reformer at near-atmospheric pressure, while HYL reforms gas internally at a much higher 6 to 8 bar, which shifts the maintenance focus toward seal integrity and pressure vessel checks. A single checklist that ignores this difference will miss the point that matters most for each process.
The DRI Plant Inspection Checklist
Shaft Furnace Refractory
Check the refractory lining for thinning or breakthrough risk, since this remains a leading cause of unplanned shutdowns
Reformer & Catalyst Condition
On MIDREX, inspect the external reformer tubes for alloy creep; on HYL, monitor internal catalyst deactivation, since access is more restricted
Reducing Gas Composition
Verify H2 and CO concentration and the stoichiometric ratio, since even a small shift affects DRI metallization quality
Top Gas Scrubber
Check that water content is being pulled down properly, since a scrubber running poorly adds unnecessary load to the gas compressors
Syngas Compressor & Bearings
Track bearing temperature and vibration on the compression circuit, since this is one of the highest-cost failure points on the line
Bustle Gas Injection
Inspect the bustle port and gas distribution for blockages, since uneven injection creates temperature imbalance in the burden
Hot DRI Discharge & Cooling Zone
Monitor discharge temperature stability at the furnace bottom, watching for signs of channeling or uneven descent of the burden
Pressure Vessel & Seal Integrity
On HYL's higher-pressure system, check seals and valve cycling closely, since this regime demands tighter pressure vessel discipline
Never Miss A DRI Plant Inspection Point
Oxmaint turns this eight-point checklist into a recurring digital route, capturing readings across the shaft furnace, reformer, and gas system so drift is caught weeks before it forces a shutdown. Sign up for a free trial to build your DRI plant inspection route, or book a demo to see it in action.
What An Abnormal Reading Might Be Telling You
| What You Notice |
Possible Cause |
| Drifting reformer inlet temperature |
Catalyst deactivation beginning, ahead of a bigger reforming efficiency loss |
| Rising syngas compressor bearing temperature |
Early bearing degradation in the compression circuit, a high-cost failure point |
| Uneven hot DRI discharge temperature |
Gas channeling or a bustle gas distribution blockage in the reduction zone |
| Slower valve cycling on HYL's gas system |
Seal wear under the higher pressure regime, worth catching before it leaks |
Paper Checklist vs A Digital Inspection Route
Paper Checklist
Reformer and compressor readings filed away, hard to compare over time
Easy for a busy shift to skip a check without anyone noticing
No trend line until someone manually pulls old sheets together
Digital Inspection Route
Every reading logged against the exact system or asset automatically
A skipped point flags itself instead of quietly disappearing
Trend lines build on their own, making slow drift easy to catch early
Where A CMMS Fits Into DRI Plant Inspections
Oxmaint turns this eight-point checklist into a recurring digital route, capturing each reading against the shaft furnace, reformer, or gas system asset so trends are visible instantly and a missed check never slips through unnoticed.
Frequently Asked Questions
Q
Is the inspection checklist different for MIDREX vs HYL?
Yes, both share a shaft furnace core, but MIDREX runs an external reformer near atmospheric pressure while HYL reforms internally at 6 to 8 bar, so HYL inspections weight seal and pressure vessel checks more heavily.
Q
Which check on this list matters most?
Shaft furnace refractory condition tends to matter most, since refractory breakthrough remains one of the leading causes of unplanned DRI plant shutdowns.
Q
Can a CMMS turn this checklist into a recurring digital inspection?
Yes, a CMMS can schedule the checklist as a recurring route, prompt the technician for each reading by asset, and build a trend history automatically across the shaft furnace and gas system.
Turn This Checklist Into A Route Your Team Follows Every Day
Oxmaint schedules this eight-point DRI plant inspection as a recurring digital route, capturing readings and trends automatically across the shaft furnace and gas system. Sign up for a free trial to build your DRI plant inspection route, or book a demo to see it in action.
