The pressure lock valve has the function of maintaining the pressure constant for the entire pressing time which has been preset.

This is a highly sought-after molding feature for materials that need to remain under constant pressure for a specific period of time to achieve the required level of deformation.

The pressure relief valve is installed at the top of the cylinder and acts like a tap. In fact, it has the function of preventing small oil leaks from slowly exiting the cylinder and returning to the hydraulic circuit, thus causing a progressive decrease in pressure.