4pManagement Ltd

The Brief

We were asked to assess an existing semi-automated packing line at a recent acquisition, and provide guidance on how capacity could be increased whilst automating the manual elements of the line.

After an initial site visit t was clear that the site team had a design they were keen for me to validate. Reviewing the line and understanding their growth potential allowed me to develop a three-part plan.

The Plan

The first part of the plan was concerned with how the existing line could produce more, the second was the automation of the packing area, and the third was the extension of the treat process area to match the capacity that could be installed in packing.

The Challenges

The treat is a ‘natural’ product that is dried to achieve sterility. This process, whilst allowing a high level of ‘fresh meat’, is also notoriously difficult to gain consistent weight and size between each recipe. For the primary packing particularly, this resulted in low efficiency as the packs needed constant adjustment to fit the sticks in.

We were also challenged due to the ‘grill’ mark on the underside of the stick. This cosmetic enhancement was achieved as the metal grid tray heated up in the drier and the stick dried against the steel grid. This also meant that the stick was ‘stuck’ on to the tray. Automating this removal without breaking the sticks was the primary design issue for the OEM who would be supplying the stick handling equipment.

Making Improvements

Due to these issues we were unlikely to find an OEM with a proven system, so a local OEM was engaged to come up with a design. Using a local company allowed a more dynamic design process. Finally a design for stick removal was agreed, using a plough that rolled the sticks from the tray. Tray and trolley handling was also approved as was the vision camera system from picking and placing the sticks into the infeed of the primary packing machine.

The primary packing machine was provided by the supplier who provided the original machine. It was clear that over several years they has made significant improvements to their machines, understanding the common issues. The improved access to the sealing bars, and created a detection system for missing, broken or twisted sticks.

The secondary packaging was initially to be provided by a supplier who had a long track record with the site. But part way through the specification stage a new requirement came from the client, for different pack configurations that would not be possible on the machine design as proposed. The new primary packs format would require a robotic manipulation head to get them into the secondary packs tray and hood. An OEM was found who could offer this and the specification and contract agreed.

As the build progressed it was clear that all the suppliers were suffering from shortages of electronic components due to Covid restrictions in China and Asia where a lot of these components originate from. A weekly review was set up to understand which components were short and if alternatives could be used. In the end whilst this generated a lot of tension and work, the delays were unavoidable.

The client also asked for the primary pack width to be reduced, which was built into the options on the primary packing machine, although with the proviso that the sticks had to be within the agreed specification for weight, size, and shape.

The FAT on the secondary packing was a success, but less so on the primary and stick handling. On the primary the stick rejections systems required rework and the on stick handling the sticks were not oriented correctly prior to the camera system leading to a lot of sticks recirculating, reducing the nominal speed of the line. A design change was agreed to install a vibratory conveyor to align the sticks.

The SAT for primary and secondary was achieved, although the ongoing issues of sticks out of specification was showing that to achieve the USP of this product would need flexibility in primary and secondary packs and running with the smaller pack, whilst achievable on the smaller size sticks was too much on the edge for the bigger ones.

The SAT for stick handling went to 4 rounds, each time the OEM had introduced a design change to improve the stick orientation and bring the nominal speed up to the agreed target.

This project shows the need to always have a clearly written URS, which is fully understood by the client and the OEM. Whilst the delays were frustrating for the client, all the rectification work was done at the OEM’s expense.

I would love the opportunity to find out how I can support your work. Get in touch to find out more.