At Hoodridge, we recently completed the calibration of a 9-ton process weighing hopper system used in batch processing at a local manufacturing plant. It may sound like a routine job, but the consequences of poor calibration in such systems are anything but minor.
What Is Process Weighing—and Why Calibration Matters
In industrial batching systems, processing-stage hoppers measure raw material quantities during the mixing or formulation stage. If those quantities are even slightly off, the consequences ripple downstream:
The product blend is out of spec
Batches may need to be reprocessed—or scrapped
Operators lose trust in the system
Material costs creep up unnoticed
A 1.5% calibration error on a 9-ton hopper = 135 kg per cycle. That’s enough to throw off a recipe and affect product integrity—especially in food, chemical, or fertilizer manufacturing, where formulations are tightly controlled.
The Job: Troubleshooting and Calibration
The client reported inconsistent product quality, even though their procedures hadn’t changed. That raised a red flag.
We followed a step-by-step approach:
- Visual & Electrical Inspection
Checked load cell wiring, grounding, and junction box connections
Verified there were no EMI issues or mechanical interferences - Mechanical Cleaning
Cleared out product buildup around the load cells and base—this was adding hidden weight - Test Loading and Calibration
Used certified calibration weights to simulate step loads
Adjusted the weighing controller to restore linearity across the full range
Verified repeatability and load cell signal stability - System Reporting and Documentation
Logged before-and-after deviations
Created a traceable calibration report for the plant’s QA records
After recalibration, we achieved ±0.05% accuracy, well within tolerance for consistent batch formulation.
Common Signs Your Hopper Needs Recalibration
Even if your indicator reads fine, your results might not be. Look out for:
- Fluctuating product quality
- Unexpected weight variations
- More rework than usual
- Frequent load cell errors or signal drift
- No calibration done in the last 6–12 months
- Electrical faults or maintenance done near weighing systems
How Often Should You Calibrate?
This depends on:
- Usage frequency
- Material handled (corrosive, dusty, etc.)
- Environmental conditions
- Regulatory requirements
For most production equipment, a 6-month interval is the sweet spot. For food or chemical applications, quarterly or monthly may be required.
Why This Matters for Industry
For Zimbabwean manufacturers, especially in food processing, fertilizer blending, and bulk powder handling, proper calibration isn’t just good practice—it’s a competitive advantage.
You reduce material waste.
You increase operator confidence.
You prevent expensive rework.
And most importantly—you protect the integrity of your product.
Final Word
At Hoodridge Industrial Automation, we see calibration not as a once-a-year box to tick, but as a vital part of running an efficient, profitable, and quality-driven operation.
Whether it’s a small platform scale or a 9-ton formulation hopper—precision starts with knowing your numbers are right.
If your batching process is showing signs of drift or inconsistency, we’re here to help, just reach out.
