You may have noticed black specs and carbon buildup in molding products. There are various causes for such buildup. If we have a look, the reasons may sum up as follows.
- The presence of a negative flow zone or still spots in the cylinder, nozzle, or die
- Presence of a hotspot in the machine
- If there is leftover additive, fillers, and color pigments from the delivery system
- If excessive heat, shear force, or barrel dwell time led to polymer degradation
- Unstable resin held in the machine for a considerable time
- Not following regular maintenance schedule
Other than these, the presence of contamination in raw materials can also be the cause of black specs. So again, it would be best if you talked with your supplier to have the best quality raw materials and increase your quality testing of raw materials.
How to get rid of black specs
Sometimes, the accumulated carbon will fracture, and the screw will propel it to appear as black specs in the final product. The best way to get rid of these black specs is to purge using purging compound from reputed manufacturers regularly. It is wise to purge during shutdown or startup or when resin or color change occurs.
If you contact reputed manufacturers, they will guide you to the specific grade of purging material you can use to have effective results. They also allow you to have free samples, so you can use that to notice how effective it is before placing a bulk order.
As you see above, hardware issues may also cause such black specs. If hardware issues are the cause, then you need to attend to those. Regular hardware maintenance can help you to eliminate black specs. However, it is wise to use a purging compound along with that due to the reasons that we detailed above.
If you notice that the weekend shutdowns cause black specs, it is wise to use the best quality cleaning compound from reputed manufacturers. Moreover, it is wise to use it on Friday night rather than on Monday morning. Doing such, you can avoid startup problems and shutdown for cleaning.
The ultimate thing that we need to say is that you need to use the proper nature of purging material. To help you do such, a reputed manufacturer helps to have free samples. Using such a sample, you can understand if the nature of the material is ideal for purging. For example, in comparatively minor and modest systems, mechanical purging compounds are best in color and material transitions. But on the other hand, chemical purging is perfect for large and complex systems and ideal for avoiding issues like black specs.
If you desire to have the best quality purging compound, it is wise to contact UNICLEANPLUS. They make it possible to have samples of their purging material and use that to determine the proper material to clean your machinery. You can call them at +91 9021232809 to place your order.
Source From: https://unicleanplus.wordpress.com/
