When heating elements vary in length from one another, this may point to a defect in the compaction of the magnesium oxide (MgO) caused by a malfunction of the filling machine. The most common issues are worn-out vibration combs, a clogged filling set, and incorrect settings for filling speed and vibration frequency.
The MgO compaction is a critical factor in all subsequent production processes. For this reason, the Oakley Industrial Machinery filling machine features an electromechanical vibration system characterized by symmetrical oscillations that ensure uniform compaction of the magnesium oxide inside the heating elements.
Given the importance of MgO compaction, it is essential to verify the filling quality of the heating elements and the overall condition of the machine. This test helps operators and the maintenance team troubleshoot filler problems and reduce downtime.
A step-by-step guide, including an Excel spreadsheet, will walk you through the quality test.
The following tools are required: tubes, plastic plugs, MgO, tape, water, and a scale.
The test is based on these simple steps:
- Prepare as many tubes as there are stations on your filling machine, plus one additional tube (e.g., for a 30-station machine, prepare 31 tubes). Cut all tubes to equal lengths and set the 31st tube aside.
- Load 30 tubes onto the filling machine and number them 1 through 30. Without hanging coils, insert a plastic plug into the bottom end of each tube and start the filling cycle.
- Once the cycle is complete, manually top off each tube with magnesium oxide.
- Take the 31st tube, seal the plug with tape, and weigh it empty to establish the tare weight.
- Fill the 31st tube to the brim with water and weigh the volume of water. Record the volume in the table.
- Empty the filled tubes one by one and weigh the magnesium oxide from each tube. Record each weight in the table.
- To calculate the density of the magnesium oxide, divide the MgO weight from each tube by the volume of water.
- To verify the accuracy of the MgO density, compare the resulting density for each tube against the tap density listed in the technical data sheet of the MgO used.
If the MgO density is too low, it indicates an anomaly in the filling machine. Thanks to the initial numbering of the tubes, any irregular stations can be easily identified.
The frequency of the test should be based on how often the filling machine is in use.
For proper organization and easy reading of the data during the test, use the available Excel table.