It only seems like yesterday when Kemira Chemicals (UK) Ltd first contacted the Concetti Group for ideas and inspiration to increase production combined with greater efficiency and reliability for their automated 25kg weighing and bag filling lines.
The existing packaging lines were old fashioned, limited in packing speeds and problematic with little or no support available. Following product trials conducted in the Concetti test facility and laboratory in 2007, the Concetti Group was awarded with the supply of the innovative CONTINUA Tubular FFS machine designed for handling very demanding products and powders. Now in 2012, Kemira have installed the fourth Continua line completing the program of upgrades to their bagging systems.
The product handling starts with the Concetti electronic net gravity fed weigher designed for handling free flowing powders. In the bag filling industry, the weighers integrated are dynamic in operation meaning the product handled is fed and weighed simultaneously into a hopper prior to discharge into the bag (net weighing). Due to this dynamic operation, although the design of the weighing mechanism is important, and can influence the final performance of the weigher in terms of speed and accuracy, the most vital consideration should be focused on the weigher feed system and control philosophy. Careful analyses should be given to the materials to be handled, their characteristics such as bulk density, particle size, flowability and fluidisation in deciding the most suitable feed device.
The feed system controls the product from the feed hopper into the weighing machine. The product must be under total control throughout the weighing cycle, most commonly 2 stage feed for main and minor feed, (progressive feed is also available for high speeds using brushless motors). The final product feed cut-off must be carefully engineered and accurately controlled, mainly due to the product feed and “in-flight” material. Control of the feed rate is paramount to enable the “in flight” material to be consistent throughout, should this become erratic or variable, accurate weighing is impossible.
The weigher chosen for Kemira Chemicals was the Concetti net gravity designed for handling free flowing granules and powders, feed gates radial in construction with teflon coated contact parts and featuring internal adjustments to control the feed rates in both main and minor feed cycles.
The unrivalled performance of the Concetti weigher was demonstrated with the final test results showing an accuracy of less than 8gr sigma 1 (68% of weighments within +/- 7.5gr of the 25kg target weight).
The Concetti CONTINUA bag filling machine positioned underneath the weigher is a Tubular FFS (Form Fill Seal) designed to produce bags formed from a tube of plastic and wound into a reel. Continua is a special machine designed for handling a huge variety of demanding products including fluid powders, abrasive construction materials, corrosive granules/flakes and free flowing petro-chemical plastics.
Continua is available with many features that can be applied to specific applications such as product de-aeration probes, special coatings for product contact surfaces, bag compacting, residual air evacuation, upper edge seal area cleaning, seal cooling and inert gas purging (MAP). Dust problems are confined to history with our new generation of bag holders guaranteeing a dust and spillage free operation.
To increase the bag stability and shape, Continua also features the K-Sealing option, creating a block style bag perfect for palletising highly presentable, safe and compact loads.
For Kemira Chemicals, the accurately filled, clean, stable and square shaped bags are presented to the existing palletiser system, another example of the success of Concetti Group technology.
Dave Goult, Site Manager of Kemira Chemicals (UK) Ltd says “Concetti Continua performance and plant availability through their commitment to the highest levels of professional service made the choice for investment an obvious one. I would have no hesitation in recommending Concetti packaging machinery to anyone thinking of installing or upgrading a packaging facility”