A field trial is the most reliable way to determine whether a customized hardfacing solution can deliver meaningful service-life improvement in a real operating environment. Laboratory abrasion tests are useful for material ranking, but actual equipment is exposed to changing loads, abrasive particle size, impact, temperature, moisture, operating speed and maintenance conditions. A well-designed 2–3 month trial can therefore provide much stronger evidence than a single laboratory number.

The key is to treat the trial as a controlled engineering experiment rather than simply installing a new wear plate and waiting for it to fail. The test area, baseline condition, measurement method, operating variables and acceptance criteria should be defined before installation.

1. What a 2–3 Month Field Trial Should Prove

The objective should be stated in measurable terms. “The new overlay should last longer” is too vague for a scientific comparison. A better objective is to determine whether the customized formulation produces a measurable reduction in wear rate under the same operating conditions.

A useful trial can answer five questions:

• Does the customized material wear more slowly than the existing material?
• Is the wear rate stable throughout the trial?
• Does the overlay develop cracks, spalling or carbide pull-out?
• Does performance remain consistent across different locations?
• Can the measured wear rate support a realistic service-life prediction?

2. Start with a Baseline Before Installation

A baseline is essential because a field trial has little value if the original wear rate is unknown. Before installing the trial material, record the condition of the existing component and its historical performance.

Whenever possible, record both wear per operating hour and wear per ton of processed material. The second metric can be particularly useful when production volume varies during the trial.

3. Select the Right Trial Location

The test location should represent a meaningful wear zone. Installing the trial material in an area with unusually low wear can produce an impressive result that cannot be reproduced elsewhere.

Suitable locations usually have:

• Known and repeatable material flow
• Significant historical wear
• Accessible inspection points
• Stable component geometry
• Comparable loading conditions
• A clear replacement or failure criterion

For large equipment, several small trial sections are often more informative than one large section. Different positions can then be compared under the same operating period.

4. Use a Control Section Whenever Possible

The strongest field trial includes a control section. One section remains with the existing material while another uses the customized overlay. Both sections should operate in the same equipment and experience the same abrasive stream.

This approach reduces the influence of changing production conditions. If the entire machine is converted to the new material, a reduction in wear may be caused by lower production, smaller particles, reduced impact or another operational change rather than the material itself.

5. Define the Measurement Grid Before the Trial

Random measurements are difficult to reproduce. A fixed measurement grid should be established before the trial starts. Each point should have a unique identification number or position reference.

For a rectangular wear plate, for example, measurement points can be arranged in rows and columns. The same locations should be measured at every inspection. This creates a time series rather than a collection of unrelated measurements.

6. A Practical 2–3 Month Inspection Schedule

A short trial should contain several inspection points. Waiting until the final day provides too little information about how the wear developed.

If the equipment operates continuously, inspections can be scheduled by operating hours instead of calendar dates. This is often more scientifically meaningful when production is irregular.

7. Measure Wear Rate Instead of Looking Only at Thickness

Remaining thickness is useful, but the key performance indicator is the wear rate. If the initial thickness is known, the basic calculation can be expressed as:

For production equipment, another useful metric is:

These values allow the new material to be compared with the control section even when production volume changes during the trial.

8. Do Not Ignore Local Maximum Wear

Average thickness loss can hide the most important failure location. A component may show a small average loss while one local area is already close to perforation.

Three indicators should therefore be tracked separately:

• Average thickness loss — overall wear behavior
• Maximum thickness loss — local critical wear
• Wear distribution — whether the damage is concentrated or uniform

The maximum-wear location should be photographed and measured at every inspection. If the same area consistently develops the highest wear, it may reveal a flow or impact problem in addition to a material limitation.

9. Record Operating Conditions at the Same Time

Material performance cannot be evaluated correctly if operating conditions are ignored. During each inspection, record the variables that may affect wear.

10. Combine Thickness Data with Visual Inspection

Not all failure mechanisms appear as simple thickness loss. A hardfacing layer can show cracking, delamination, spalling, carbide pull-out or localized impact damage before substantial average thickness loss occurs.

Each inspection should therefore include standardized photographs. The same viewing angle and approximate distance should be used whenever practical.

Record the following conditions separately:

• Surface cracking
• Transverse or longitudinal cracks
• Spalling
• Delamination
• Carbide pull-out
• Local gouging
• Plastic deformation
• Substrate exposure

A visual defect should not automatically be classified as failure. The engineering significance depends on its depth, growth rate, location and relationship with the service environment.

11. Use the Wear Rate to Estimate Service Life

After several measurements have been collected, a preliminary service-life estimate can be developed. If the wear rate remains approximately stable, the remaining usable thickness can be related to the measured rate.

This is a projection, not a guarantee. Wear rates may accelerate when the surface becomes thinner, operating conditions change, or the matrix and hard phases respond differently near the end of the overlay life.

For this reason, the safest approach is to use the 2–3 month result to establish a preliminary wear trend and then validate the prediction against longer-term operating data.

12. Establish a Quantitative Acceptance Criterion

A trial should have a predefined acceptance criterion. Without one, the conclusion may become subjective.

For example, the project may define success as a specified reduction in normalized wear rate without unacceptable cracking or delamination. The actual threshold should be agreed before the test rather than changed after the result is known.

13. Control the Variables During the Trial

The most common problem with field trials is uncontrolled operating variation. If the abrasive changes significantly halfway through the trial, the material should not be judged as though the conditions were constant.

Major changes should be documented, including:

• Changes in feed material
• Changes in particle size
• Changes in production rate
• Changes in operating speed
• Changes in moisture content
• Changes in equipment configuration
• Unexpected shutdowns or overload events
• Maintenance or repair work

When a major operating change occurs, mark it clearly in the test record. This allows the later analysis to distinguish material performance from operational effects.

14. Statistical Thinking for a Small Field Trial

A 2–3 month test may provide limited data, but it can still be structured scientifically. Multiple measurement points should be treated as repeated observations rather than as one number.

At minimum, calculate the mean, minimum, maximum and range of thickness loss. If enough repeated measurements are available, standard deviation can also be used to describe variation.

Do not focus only on the single best measurement. A material that performs exceptionally well at one location but poorly at another may have a distribution problem that is more important than its average value.

15. How to Decide Whether the Custom Formulation Has Passed

The final decision should combine quantitative and qualitative evidence.

If only one of these indicators improves, the conclusion should remain cautious. For example, higher hardness with increased cracking may not represent an overall improvement.

16. A Recommended 90-Day Field Trial Structure

17. What the Final Trial Report Should Contain

A professional field-trial report should allow another engineer to understand exactly how the conclusion was reached.

• Equipment and component description
• Existing material and baseline service life
• Customized overlay specification
• Installation date and operating hours
• Trial location and control location
• Measurement-point diagram
• Thickness measurements at each inspection
• Operating conditions during each period
• Photographs of representative wear zones
• Crack and spalling observations
• Wear-rate calculations
• Comparison with the control material
• Service-life projection
• Final acceptance conclusion

This documentation also becomes valuable for the next production batch. Once a successful formulation has been validated, the field data can be converted into a repeatable material specification and inspection plan.

Sinter Plant Wear Plate

Ball Mill Liner Wear Plate

Steel Mill Liner Plate

Blast Furnace Wear Plate

18. Teda Ganghua Support for Wear-Resistant Material Trials

Teda Ganghua supports industrial customers with wear-resistant steel and material solutions for demanding abrasion applications. For customized wear projects, the field-trial method can be used together with material specifications, hardness requirements, dimensional requirements and inspection data to create a more complete performance-validation process.

For applications in mining, cement, aggregate, coal handling, material conveying and construction equipment, customers can review the available wear-resistant steel solutions and define the trial material according to the actual operating environment.

A useful commercial evaluation should not stop at “sample approved.” The strongest approach is to establish a baseline, install a controlled trial section, collect repeated measurements and compare normalized wear rates. This creates evidence that can be used for future purchasing specifications and production decisions.

FAQ

Is 2–3 months long enough to validate a hardfacing formulation?

It can be enough for a preliminary field validation when the component has a high wear rate and operates continuously. The trial should be long enough to produce measurable thickness loss and multiple inspection points. For low-wear applications, a longer period may be necessary.

Should a control material be installed during the trial?

Yes, whenever equipment geometry allows it. A simultaneous control section provides a stronger comparison because both materials experience approximately the same operating conditions.

What is the best way to measure wear during a field trial?

Use fixed measurement points and repeat the same measurements at each inspection. Thickness loss can then be converted into wear rate and normalized against operating hours or processed material quantity.

Can visual inspection replace thickness measurements?

No. Photographs are valuable for detecting cracking, spalling and local damage, but quantitative thickness measurements are needed to establish a reliable wear trend.

Does a lower wear rate guarantee a longer service life?

Not necessarily. Service life also depends on the minimum usable thickness, cracking, delamination, impact damage and other failure modes. A reliable prediction should consider both measured wear and the actual failure criterion.