Knowing that refractory is wearing isn't the same as knowing how much lining is actually left. A hot spot tells you something is thin, but only a thickness measurement tells you whether that zone has months of life left or needs attention at the next stop. This checklist covers how to measure refractory thickness properly and what to do with the numbers once you have them. Sign up to log thickness readings against the kiln asset and watch the wear trend build automatically.
3 Methods
Common ways plants measure remaining refractory thickness
±1mm
Typical accuracy achievable with ultrasonic thickness testing
Same Points
The one rule that makes readings comparable over time
Every Stop
Minimum frequency recommended for a full thickness survey
Why A Single Reading Isn't Enough
One thickness number tells you where a zone stands today. It's the trend across several shutdowns that tells you how fast it's wearing and when it will actually need attention. Measuring the same points, the same way, every time is what makes that trend meaningful.
Measurement Methods To Use
Ultrasonic Thickness Testing
Use for precise point readings on accessible sections, ideal for tracking a known wear zone over time
Laser Profile Scanning
Use for a full internal profile in one pass, useful for spotting uneven wear across the whole lining
Manual Spot Checks
Use as a quick backup method at known problem zones when scanning equipment isn't available
Turn Thickness Readings Into A Real Wear Trend
Oxmaint stores every thickness reading against the exact zone it was taken from, so the wear curve builds itself across shutdowns instead of living in separate reports. Sign up for a free trial to start tracking thickness by zone, or book a demo to see it in action.
Recording & Trend Monitoring
Mark Fixed Reference Points
Measure the same grid points every time so readings can be compared shutdown to shutdown
Log Original Lining Thickness
Keep the as-installed thickness on record so wear rate can be calculated, not just the current reading
Set A Minimum Thickness Threshold
Define the point at which a zone gets flagged for relining, and check every reading against it
Choosing The Right Method For The Job
| Method |
Best Used For |
| Ultrasonic testing |
Tracking a specific known wear zone at high precision over repeated visits |
| Laser profile scanning |
Getting a full internal profile quickly to spot uneven wear across the lining |
| Manual spot check |
A fast confirmation at a suspect zone when full scanning isn't practical |
| Shell infrared scan |
Flagging where a direct thickness measurement is worth taking in the first place |
One-Off Spot Checks vs A Continuous Trend
One-Off Spot Checks
Each reading sits alone, disconnected from the last shutdown's numbers
Wear rate has to be worked out manually, if at all
A thin zone is often noticed only after it becomes urgent
Continuous Trend Tracking
Every reading builds on the last, tied to the same zone
Wear rate and remaining life calculate themselves over time
A zone crossing its threshold gets flagged before it becomes urgent
Where A CMMS Fits Into Thickness Monitoring
Oxmaint stores thickness readings against fixed zones on the kiln asset, so wear rate and estimated remaining life are calculated automatically instead of being pieced together from old inspection reports.
Frequently Asked Questions
Q
How accurate is ultrasonic refractory testing?
Ultrasonic testing typically achieves accuracy within about one millimeter, which is precise enough to track gradual wear reliably across multiple inspection cycles.
Q
Why do readings need to be taken at the same points every time?
Refractory wears unevenly, so measuring different spots each time makes it impossible to tell whether thickness is actually dropping or you simply picked a different point.
Q
Can a CMMS calculate remaining refractory life?
Yes, once original thickness and a minimum threshold are set, a CMMS can use the wear rate from past readings to estimate when a zone will need relining.
Know Exactly How Much Refractory Life Is Left
Oxmaint turns scattered thickness readings into a clear wear trend by zone, so relining decisions are based on data instead of a guess. Sign up for a free trial to start tracking thickness by zone, or book a demo to see it in action.
