Automation solutions specialist Sewtec Automation has devised and installed a bespoke robotic top-load system for the packing of flow wrapped tea bags at leading tea supplier Twinings’ Andover factory.
Three specially designed Sewtec LX5249-2 robotic machines are packing boxes of 40, 80, 160 and 240 tea bags with minimum changeover requirements. In addition, a unique integrated buffer storage system is able to store up to ten minutes worth of production and reintroduce the packs during normal production, in order to maximise throughput while maintaining overall line efficiency and product quality.
The Sewtec system was created to meet Twinings’ requirements for a fast and efficient means of packing its new flow wrapped packs of tea bags. As well as maintaining the freshness of the tea, the special film used is biodegradable, thus minimising the packaging’s environmental impact.
Four IMA tea bag machines linked to four PFM flow wrappers transfer pillow packs into the Sewtec designed conveyor and gating system, which channels the packs to the three robotic box loaders. At the same time top load boxes are automatically erected, conveyed and fed into compartment racetracks within the box loaders.
The Sewtec designed pick and place robot features twin axis servo motion control for consistent and reliable operation. The vacuum pick and place tooling has been specially designed for this application to ensure gentle but firm handling of the lightweight, loosely wrapped packs. The packs are picked from compartment racetracks, spaced and pitched according to the required loading format and placed into the boxes. The system is configured to pack single/single stacked wraps into eight boxes simultaneously or twin/twin stacked wraps into four boxes simultaneously, with minimal changeover time at a rate of up to 120 flow wraps per minute. Changeovers between the different sizes can be carried out at the touch of a button with just the guides for the different carton sizes needing to be changed.
A major innovation of the system is the availability of an integral buffer storage system. If for any reason, there are stoppages further down the packing line, the machines are able to divert product away from the robotic top loader into an integrated store. Each pack is individually handled and placed into storage from race track compartments, eliminating any queuing or bunching of items in order to maintain product quality. Up to ten minutes storage is available and packs are then automatically reintroduced into the packing line during normal production.
A significant challenge of the installation was the limited amount of space available in the factory for all the new equipment. Sewtec devised and installed a series of alpine conveyors to link the carton erectors and top loaders in order to ensure easy access around all the machines
“Sewtec’s ability to produce well engineered and reliable machines with innovative and flexible design helped to make this project such a success,” comments Ken Crowther, Twinings’ Planning Engineer.
“The company’s professional pro-active approach was invaluable as the lines were phased into production one at a time, and Sewtec remained on site until all lines were running to specification, thus ensuring that the project was completed in full and on time. I would not hesitate in recommending the company for future projects.”
Sewtec Automation Limited
Tel: 44 1924 494047