Weigh VS Volumetric Batching
Weigh Batching
Process Overview
Batched when all other ingredients are batched
Discharged quickly at required location in cycle
Process Considerations
More time for batching enables lower flow rates
and improved dosing accuracy.
Rapid discharge and full batch computer
functionality ensure admixtures are dosed
optimally with no impact to production.
Out of Tolerance Batches
- Are Identified prior to discharge from Scale
- Dumping or correction only affects admixtures
in scale, not full load
Drives Appropriate Decision Making / Actions
The full sophisticated functionality e.g. inflight,
self-learning, etc. of the batch computer is used,
improving accuracy
Correcting NC batches is simple and cheap – dump
non-conforming admixture and re-batch that
admixture
Calibration, Accuracy & Verification of Accuracy
Calibration compliance requirements are Onerous – within +/- 0.4% of maximum scale value.
Accurate to the magnitude of an individual scale division – typically 10 grams (approx. 9 to 10 ml)
Scale which are responsible for batching multiple admixtures are calibrated
Push-button automatic scale checking enables frequent accuracy verification and minimizes the impact of issues.
Operation
Simple proven process, fully controlled by Batch
Computer
- Starts pump
- Monitors Scale
- Using constantly optimized parameters (In
fights, etc.) batch computer stops pumps when
dosage achieved. - Verifies and records actual batch quantities
Actual batch quantities recorded accurately
Auto flushing ensure scale remains clean and free
of buildup
Robust, durable construction ensures units are
highly reliable requiring low maintenance,
provides significant technical, operational and
maintenance benefits
Maintenance
Auto flushing ensure scale remains clean and free
of buildup
Robust, durable construction ensures units are
highly reliable requiring low maintenance,
provides significant technical, operational and
maintenance benefits
Introducing a New Admixture
Connect Line from pump to spare feed pipe
Configure in batch computer no calibration required
Volumetric Batching
Process Overview
Batching and discharge is a single process
Process Considerations
Discharge options are limited due to practicality and impact on production rates.
Out of Tolerance Batches if identified
- Only identified once admixtures are in concrete
- Remedial action affects the whole load
- Rectification typically involves dumping whole
load of concrete
Can Result in Inappropriate Decisions / Actions
Reliant on batch controller functionality
Correcting NC batches has significantly greater
implications – whole load needs to be dumped and
re-batched, significantly greater cost, impacts
production, service and other deliveries
Calibration, Accuracy & Verification of Accuracy
Check compliance requirements are much wider +/- 5% of the indicated value.
Accuracy limited to individual pulse resolution, typically 50–100 mL per pulse for most admixtures.
Each dispensing line requires calibration / checking
Check and calibration process are the same, require two people and a reasonable amount of effort and time
Operation
More complex process requiring multiple systems, Batch computer
- Sends required batch quantity to volumetric batch controller
- Batch controller starts pump
- Batch controller monitors flow meter
- When dosage achieved batch controller stops pump
- Batch controller returns recorded actual batch quantity to batch computer
- Batch computer verifies and records actual batch quantities
Actual batch quantities Recorded do not always accurately reflect what was batched
Maintenance
At regular intervals (typically 3 to 6 months) flow meters bowls are replaced and dispensing lines are recalibrated. Removed flow meters bowls are either refurbished once or discarded.
At regular intervals (typically 3 to 6 months) flow meters bowls are replaced and dispensing lines are recalibrated. Removed flow meters bowls are either refurbished once or discarded.
An additional line and flow meter is required, this needs to be connected to the batch controller and the line needs to be calibrated