Measuring glass level at the feeder channel

Graphic glass production at the feeder channel

Berthold's glass level measurement couples nuclear measurement principles with an exclusive calibration configuration and procedure.  Berthold's customers replacing optical based measurements have subsequently experienced downtime reductions previously associated with high batch bin level and glass pull runaway.


  • Noncontact measurement
  • Not exposed to harsh process conditions
  • Removal of only some of the refractory bricks is necessary
  • Simple and precise adjustment of the calibration position via slides


Customer benefits

Reduce downtime associated with

  • High batch bin level
  • Glass pull runaway
  • Issues with existing optical level



Technical features

  • Measuring range:
    typically 0...5 mm to 0...30 mm
  • Accuracy:
    +/- 0.5 % of the measuring range
  • Achivable resolution 0.05 mm
    (0.002 in)



Reliable glass level measurement arrangement and control

Nuclear level source and detector are both mounted external to the furnace refractory.  In some cases, a refractory "cutout" may be required in the exterior refractory layer. In these cases, however, harsh furnace conditions are still contained within the inner refractory layers.

Alignment and calibration

Berthold utilizes linear slides to provide accurate, repeatable, and robust glass level measurements.  During calibration, raising and lowering the radiation source and radiation detector in lockstep is critical to ensuring an accurate calibration. Berthold's linear slides and multiple calibration points provide customers with best in class float glass level reliability and accuracy.

Berthold's measurement solution

DuoSeries LB 470

Radiometric level measurement DuoSeries LB 470 2-wire technology


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