Three main factors affecting the tolerance of silicone tube
Every enterprise produces tolerances when producing products, and this tolerance is related to many factors. When the silicone tube produced by Shunbo undergoes high-temperature vulcanization, the tolerance will be affected by factors such as the temperature of the machine head and the melting point of the extruded material. The following editor will explain the main three factors that affect the tolerance of the silicone tube. Big factor:
   1. Due to the influence of the head temperature.
Under the same extrusion conditions, if the temperature of the die is too low, the inner diameter of the extruded silicone sleeve becomes larger, and the wall thickness of the silicone hose becomes thinner; when the extrusion temperature is higher, the inner diameter of the silicone hose becomes smaller. Then the wall thickness of the silicone hose becomes thicker.
2. Due to the influence of the melting point and fluidity of the extruded material. The flow performance of the material is closely related to the temperature. As the temperature increases, the apparent viscosity of the material decreases and the flow performance is good. When the temperature of the die head decreases, the apparent viscosity of the material is higher, and the flow performance is poor. The forced extrusion increases the pressure of the die head. The tube blank from the die will recover elastically due to the release of the stress, and its expansion degree will also be the same as before. It is proportional to the pressure, and the poor fluidity of the material makes the material less extruded, which causes the inner diameter of the silicone hose to become larger, and the wall thickness becomes thinner. With the gradual increase of temperature, the flow performance of the extruded material in the die is improved, and the pressure of the die is reduced accordingly, and the amount of elastic recovery of the release tube due to the stress is correspondingly reduced, and the inner diameter of the extrusion is reduced; , The amount of material squeezed out increases with the improvement of flow performance, which makes the wall of the silicone hose thicker.
3. The influence of different screw speed and traction speed. At the same temperature, the pipe diameter and wall thickness of the extruded silicone sleeve have a great relationship with the screw speed and traction speed. As the extrusion speed increases, the inner diameter of the silicone sleeve will become larger and the tube wall will become thinner. The lower the temperature of the die, the more obvious this change will be. This is mainly because with the increase of the extrusion speed, although the viscosity of the material decreases with the increase of the shear stress (shear strength), due to the higher processing pressure of the silicone melt and the increase of the extrusion pressure, its viscosity It has also improved. At this time, the flow performance of the material depends to a large extent on the external heating temperature.