IVAC simplifies work and reduces costs for extruder manufacturer

Extruders are a key component of mechanical industrial production, used for applications from profiles for windows to envelopes for skyscrapers, from components for the construction of locomotives and railway carriages to metallic elements for lorries. Their design and construction must meet numerous requirements in terms of strength, safety, certification, functionality and stability.

One recent project aimed at optimising quality and production efficiency at Presezzi centred on the renewal of cylinders used in the metal extrusion process and, in particular, the billet loader. The billets - giant ingots of aluminium, hard alloy, copper and brass - have to be loaded to be taken from the oven to the centre of the press. During this process, the billet loader is operating in a harsh environment where temperatures can exceed 450degC and sparks are frequently present.

The standard loaders used previously were equipped with pneumatic cylinders controlled by a valve. This was an external component that had to be purchased and installed in various steps, depending on the configuration and installation of the tubing, to move the cylinder forwards and backwards.

Depending on the type of press, the tubes had to be tailored for each cylinder, setting lengths and tolerances each time through a lengthy and delicate process. Moreover, hydraulic rather than Rilsan tubes were used due to their heat resistance properties, meaning the tubes were much larger and more expensive.

Presezzi Extrusion consulted experts from Norgren about an alternative approach, with Norgren proposing the use of its IVAC systems. These are new-generation cylinders which offer several advantages by having the valve built in. This not only eliminates the initial phase of assembling the valve within the cylinder, but also optimises the space inside the loader, in which there are other elements to be wired and adjusted, such as flow regulators and magnetic sensors. Thanks to the layout of the cylinder, IVAC solves part of the complexity relating to the internal components. Reducing the size of the apparatus allows Presezzi to make the structure more efficient. The fact that everything is inside the unit also increases safety, protecting the unit from the external environment. In addition, eliminating the air tubing between valves and actuators reduces air consumption by up to 50 per cent, significantly cutting costs per mm of stroke compared with conventional pneumatic systems.

Continuity of operations

Compared with previous results, the introduction of IVAC has halved processing times, and maintenance operations have been minimised thanks to the simplicity of disconnecting the tube and its connector and replacing the cylinder. Given that the machines operate 24/7, Presezzi can guarantee the continuity of its operations as downtime for maintenance is minimised.

Presezzi Extrusion is now planning to extend the use of the IVAC cylinders to other types of machinery in the extended supply chain, supporting the upstream and downstream presses, where the pneumatic section is much larger.

Emiliano Pirola, Head of Pneumatics and Hydraulic Installations, explains: "The process of assembling the valves and reconfiguring the tubes used to be long and laborious. First we ran a tube into the valve, then ran two more tubes out the valve to aid the control of the cylinder and motion dynamics. In addition, we had to wire the solenoid valve that controls the cylinder. Given that each press has a magazine with between four and six cylinders, there were between 12 and 18 tubes to be configured and installed.

"However, the use of Norgren's IVAC cylinder has led to considerable improvements in terms of work simplification and cost reduction. The engineering of the cylinder is such that the entire application process is simplified. The solution not only allows us to cut the cylinder's operation time, minimise space and installation operations, but also increases the efficiency, speed and quality of our work. We control the cylinder with a single air tube and connector inside the IVAC. The incoming tube is then split between four or six cylinders, halving the number of tubes involved."

For further information about IVAC (Integrated Valve & Actuator Control) cylinders visit www.norgren.com/ivac.