There are several disadvantages to using a fixed pump injection molding machine:
- Limited injection speed: The injection speed of a fixed pump machine is limited by the pump's maximum output flow rate. This can be a problem when trying to inject high viscosity or heavily filled materials, which require higher injection speeds to fill the mold properly.
- Poor energy efficiency: Fixed pump machines are generally less energy efficient than variable pump or servo pump machines. This is because they are designed to deliver a constant flow rate, regardless of the actual demand for flow. This leads to higher energy consumption and higher operating costs.
- Limited control: Fixed pump machines offer limited control over the injection process. This can be a problem when trying to achieve precise shot sizes or when trying to mold thin-walled parts that require very precise injection pressure and speed control.
- Limited flexibility: Fixed pump machines are not as flexible as variable pump or servo pump machines, which can be easily adjusted to accommodate different molding processes or materials. This can be a problem when trying to mold a wide range of products or when switching between different materials.
- Higher maintenance requirements: Fixed pump machines typically require more maintenance than variable pump or servo pump machines, due to the presence of mechanical pumps and other mechanical components that are prone to wear and failure.
