Pet project

Nestlé Purina Pet care recently upgraded its packaging lines during a comprehensive retrofit of its production facilities to serve the rapidly growing business.

The global manufacturer of dog and cat food, based in Aubigny, France, manufactures around the clock with production facilities running seven days a week, involving a variety of product and packaging cycles.

The quality and the functionality of packaging lines is critical, says the company, because these must meet the highest requirements in terms of productivity, flexibility, reliability and absolute safety.

A rise in production meant that the company’s existing technology had reached its limit. With the quality of its products cited as its top priority, the aim of the upgrade was to achieve a highly flexible, safe production process to meet these expanding production requirements.

Continuously changing production cycles demand an automation technology that can be tailored flexibly to the each of its packaging processes, says Nestlé Purina Petcare.

This was why it opted for the PSS 4000 automation system from Pilz. It says key benefits of the system are that it can be used to implement standard as well as safety-related automation tasks simply and above all flexibly, as changes in the packaging process are continuously repeated.

Before the upgrade, the packaging line was controlled via a relay-based solution, which assumed control of safety functions such as emergency stop, light beam devices and door locking devices.

The modernisation work on the packaging lines comprised a full upgrade of the control components.

Nestlé Purina Petcare says the PSS 4000 automation technology was easy to integrate into the plant’s existing structure.

The system also allowed the hardware and software design to be developed independently of each other which meant that the required hardware could be defined faster because the system and hardware development ran in parallel.

Nestlé Purina Petcare says the key selection criteria included flexibility, easy operation, simple diagnostics via the corresponding software platform PAS 4000, and data transfer via the real-time Ethernet SafetyNET p, which enables all data to be transferred safely.

The real-time Ethernet adapts to the existing data transfer structure and uses the existing Ethernet – Modbus TCP - to communicate with the distributed remote station’s PSSuniversal I/O and the automation system’s higher-level control system’s PSSuniversal PLC.

Safety data from the individual stations and the installed operator terminals is transferred in real-time, as is the data from the packing stations.

PSS 4000 also enables all data to be managed on a decentralised basis, so if one of the seven areas on a packaging line has to switch to a safe condition in the case of danger, the other areas will continue production, so that the overall process is not interrupted.

“Standstill times were reduced significantly thanks to the improved diagnostic function,” says Thierry Jouval, project manager at Nestlé Purina Petcare.

Nestle says the PSS 4000 offered simple installation, programming and the added benefit that the software can be created independently of the hardware via the corresponding software platform PAS 4000. With many of these applications, the focus was on potential expansions to the plant and therefore a very high degree of flexibility was required.

As a result of ongoing developments in the PSS 4000 - such as a new Editor in accordance with EN/IEC 61131-3 for standard and safety, and the control system PSSuniversal multi - even greater scalability is possible, says Nestlé Purina Petcare.