Rubber hoses are common items in everyone’s life. Most rubber hoses are produced by extrusion. What are the factors that affect the formation of rubber hoses? As a professional rubber tube manufacturer, I will explain it to you.

1) Temperature The increase in the melt temperature θR and the mold temperature θM causes the degree of orientation to decrease. This is because, after the temperature rises, although the deformation and flow of the melt are favorable, the degree of orientation may increase, but at the same time, the de-orientation ability of the polymer grows faster, and the result of both functions is often the orientation. The influence is dominant, so the degree of orientation is reduced.

2) Injection pressure and holding pressure Increasing the injection pressure and holding pressure can increase the shear stress and shear rate in the melt, which helps to accelerate the orientation process and increase the degree of orientation and product density.

3) Gate Freezing Time After the melt fills the cavity and stops flowing, the thermal motion of the melt is still severe for a certain period of time, and the structural unit that has been flow-oriented is likely to be de-oriented. However, when a large gate is used, the melt cools slowly in the gate, the gate freezes later, and the flow process is delayed, so that the disorientation caused by molecular thermal motion can be compensated to a certain extent, especially Near the gate, the orientation is very significant.

4) Mold temperature When the mold temperature is low, the movement of the macromolecule of the polymer is easily frozen, so the ability to de-orientate is reduced, and the degree of the orientation is increased.

5) Filling speed The influence of filling speed on the curve process can be divided into two cases: fast filling and slow filling.

1 When filling the mold quickly: When filling the mold quickly, due to the flow rate, the surface of the product can be highly oriented near the surface, but the internal temperature is much slower than the normal filling, so the solution orientation is enhanced and the degree of orientation is higher. Slightly near the surface.

2 When filling at a slow speed: When filling slowly, the contact time between the melt and the surrounding interface (flow path and cavity wall, etc.) is long, and more heat is taken away by the mold at the same injection temperature. Compared with the rapid filling, the relaxation time of the macromolecule is shortened, the ability to de-orientate is lowered, and the degree of orientation is improved. In addition, a large injection pressure is often required for slow filling, so the degree of orientation will be further improved.