Tsubaki Chain Proves To Be a Hero at Cadbury


Tsubaki conveyor chain has enabled Cadbury to significantly increase production on an automated Bindler chocolate moulding plant at the company's Bournville works in Birmingham. The wear characteristics of the chain previously fitted to the machine meant that frequent adjustment was required to maintain accuracy and replacement was required every twelve months. The new Tsubaki chain has been in operation for over six months and has not yet required any adjustment. Maintaining this level of accuracy has also allowed throughput on the machine to be increased, resulting in a production increase of thousands of chocolates per day.

The Bindler machine is a fully integrated chocolate moulding plant, used to produce chocolates with centres such as Roses™, Milk Tray™ and Miniature Heroes™.

The chocolate making process starts with a mould tray being brought to the correct temperature, a chocolate shell is then deposited into the mould, a centre such as cream, noisette or strawberry is then added and passed through an intense cooler that freezes it before the chocolate back is deposited. The back section is cooled and the chocolate is then de-moulded ready to be foil wrapped.

During the process, the moulding trays are transferred from one conveyor section to another within the plant. Any elongation of the conveyor chain caused by wear, results in the conveyors running slightly out of synchronisation and can cause tray collisions if the speed of the machine is increased passed a certain point. Frequent adjustment of the chain was also needed to maintain a high transfer rate.

Having fitted the unusual sized (20mm pitch) Tsubaki conveyor chain, there has been no adjustment required due to wear elongation for a period of over six months. As a result, the transfer operation has remained in-sync and the speed has been increased beyond what was previously possible. An additional few trays per minute does not sound like much, but with over 100 individual chocolates in each tray, the increase in throughput equates to many thousands of chocolates per day.

Tsubaki employs an advanced heat-treating process to carburize the pin surfaces of its roller chain to help achieve the improved chain performance. The link plates and rollers are also shot-peened, and the surface areas between pins and bushings and between bushings and rollers are pre-lubricated. After assembly the chains are also taken through a process of precise pre-loading and running on sprockets before being approved, packed and shipped. The result is great improvements in wear performance over other standard chains.

The first trials at Cadbury have proved so popular that Tsubaki metric pitch attachment chain is now being specified as standard replacement stock for all Bindler machines at the Bournville site.

– 2004 April 1