The first: Use factor
1. The melting temperature is too low, lower than 720 degrees Celsius. The melting temperature is inversely proportional to the melting speed. The melting temperature is too low so that the sample will not melt sufficiently and then slowly melt over time.
2. The braising time is too short, and it is recommended to reach more than 10 minutes.
3. Stirring time is too short, should be required to reach at least 8 minutes, the longer the better, to prevent segregation.
4. The order of feeding is not ideal, the temperature reaches the melting requirements, should try to put additives first.The more complex the composition of the aluminum solution, the more it will affect the melting of the additive.
5. The scum is not good, the scum is too thick, the additive has not sunk into the bottom of the furnace, floating on the surface of the scum.
6. The deviation of the analysis value, the pre-furnace analysis value is not allowed, especially when the proportion of waste is large, because the waste is not classified management, can not calculate the accurate pre-furnace value, if the pre-furnace analysis value is not allowed, the calculated additive input amount is not allowed, the final actual yield will not be allowed.(the sample analysis has a large difference, so the segregation can be determined)
7. The sampling method is wrong. The correct sampling method is to take two samples from both sides of the furnace door and take the average value.
8. Short sampling time: at least 25 minutes after feeding, including 10-15 minutes for braising and 10 minutes for stirring.
9. Crushing use.Some customers will break the additive after use, will produce a large number of powder, causing unnecessary burning damage, resulting in low actual yield.
10. Analysis of the reasons for the instrument, the standard sample is not standard (probability is very low).
11. Analysis error may also lead to inaccurate actual yield. For example, when the proportion of additives is very small, for example, only 20 kilograms of additives are put into 20 tons of aluminum solution, and the target value is only increased by 0.07%. The 0.007% assay error will affect the actual yield of 10%. Generally speaking, the 0.007% assay error is very easy to produce.
The second: Product factor
1. Product quality problems: moisture absorption, oxidation and rust, powder proportion, be pressed too hard;
2. Product segregation or content does not meet the standard;
3. Slow melting due to defects in raw materials or formulations, Through the static furnace (insulation furnace) and the change in the element content of the end product, it can be determined.
The last: Others factor
1. Wrong calculation method, inaccurate data, etc.