What are the reasons for the significant vibration in expansion dryers?
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Our company’s SBS production line has just started operations. One of the expansion dryers, model PG350, experiences significant vibration; this is manifested in excessive vibration in the cutter system that is mounted in a cantilever configuration, which affects the uniformity of the length of the rubber particles being cut – some particles are 1-2 millimeters long, while others are around 30 millimeters long； At the same time, the steam pipeline also experiences significant vibration ； There is no rigid connection between the vibrating fluidized bed and the expansion dryer, and the fluidized bed does not generate reverse vibration to the unit. My analysis: 1. The cutting tool system of Dalian Tiansheng is mounted in a cantilever configuration, which amplifies the vibration of the unit. 2. The bolts that support the cutting tool system may be loose. 3. It is possible that the concentricity of the coupling does not meet the requirements, but the manufacturer has not provided an alignment curve. 4. The cylinder supports and anchor bolts may be loose. May I ask what other reasons does Haiyou have?
Unstable die pressure can also cause the cut rubber strips to vary in length; first tighten all the bolts and then check if the vibration is still significant
Also, is the position of the cutting blade installed in a vertical direction?
Reply to 3# pliang06: Thank you for your participation! Due to the heavy cutter motor (PG350 in this unit), the cantilevered cutter system naturally sags, causing the axis of the cutter shaft to be perpendicular to the template surface. Previously, when the vibration was not severe, the pellet length was still uniform ； However, after vibration, the distance between the cutting blade surface and the template surface increases, resulting in greater inconsistency in the length of the pellets.
Previously, this phenomenon did not occur in our equipment, which used French-made devices; however, due to poor polymerization, the particles produced were sometimes quite long. Additionally, excessive compression can also cause the polymer particles to become longer. Also, check the cutting blade to see if it’s worn or dull
Reply to 1# Worker Wang01: The template can be removed to clean the mold holes
Reply to 5# pliang06: Hello! Thank you for your reply! Unstable molding can affect the vibration of the machine. It is likely that in my case the cutting tool assembly has worn out and sagged due to vibration, as well as from its own weight, which leads to resonance in that assembly. I analyzed it this way because, after trying to reduce the cutter’s rotational speed, I unexpectedly observed that the vibration level of the cutter unit decreased.
Unstable feed rates, which fluctuate greatly, not only cause vibration in the expansion dryer but also affect particle cutting by the cutter. It is recommended to modify the way the cutter is installed, for example by using concentric cutters.
Hello,,, have you ever encountered a situation where the spindle broke?