Because of a number of variables inherent to the production of candy, Astra Sweets did not know the exact weight of production runs coming off the three casting lines. Discrepancies in the buffer stock of semi-finished products caused rest materials, delivery delays and additional, corrective production runs. Now RAVAS mobile weighing systems have been installed on the trucks that transport the sweets form the lines to the warehouse, and accurate production weights are communicated with the ERP system over the company’s wireless network.
“At one point we started doing daily inventories to counter the problem. That cost us manpower we could have used profitably elsewhere. Using the RAVAS mobile scales we now generate real figures, and can manage on KPI’s. This realized immediate cost savings, the investment in the weighing systems earned itself back in a short time.”
- Stefan Verbeken, Manager Planning & Material Supply
Sweets from Turnhout
Meringues, wine gums, cola bottles, liquorice drops, marshmallows, peppermint: those are all products that Astra Sweets manufactures. At its main plant in Turnhout, the Belgian company produces 300 different kinds of sweets. All this confectionery is distributed under its own brand name to supermarkets, drug stores, petrol stations and wholesalers, or under private label to a range of major customers in Belgium and abroad.
On a tour through the Astra Sweets production plant, one sees lively colored sweets pouring out of machines, endless trays of sweets being stacked by robots, and trucks driving the candy to the buffer warehouse. Patrick Peeters, Key User Production, explains how things work: “Our candy is poured into starch casting molds. Depending on the type of sweets, the candy then either goes to a drying room, or to cold storage. After 36 hours a surface finishing is applied, using oil, sugar or acid. The semi-finished product then flows into trays of 9 to 13 kg candy each, which are stacked on a pallet and transported to the buffer warehouse. After acclimatization the sweets are then packaged according to customer orders.”
Corrective production and packaging runs added unnecessary cost
Buffer stock management left room for improvement, says Stefan Verbeken, Manager Planning and Material Supply at Astra Sweets. “We produce on three casting lines. Every production process has its startup losses. Add failures during a run and you can see why real output can differ significantly from the expected, theoretical output. We knew the input of raw materials of course, but we couldn’t measure the exact yield at the end of the line. Therefore we couldn’t be sure how much of any semi-finished product was in stock at the buffer warehouse. The discrepancies between the stock in our ERP and the stock in our warehouse could run into several Tons, depending on the size of the production run.”
The uncertainties in produced buffer stocks of semi-finished product led to inefficiencies and extra cost. In order to keep product switches on the lines to a minimum, all customer orders for e.g. cola bottles are grouped in a single production run, produced and then transported to the buffer warehouse. “If a semi-finished product was planned for multiple packaging orders, then this was based on the theoretical yield, with the risk that for some orders too much and for others too little was packaged. This caused last minute changes in production planning to avoid delivery problems. Extra switches in packaging runs and small, corrective casting runs added unnecessary cost. At one point we started doing daily inventories in the buffer warehouse to avoid this, spending a lot of man-hours.”
The key to improvement: mobile weighing
An improvement project was started: all candy coming off the lines was going to be weighed. Different options were considered: integrating weighing systems in the production lines proved expensive, weighing on a floor scale time consuming and possibly unsafe because of logistic bottlenecks in warehouse traffic. Patrick Peeters had had experience with RAVAS at a former employer and proposed to weigh mobile, on the warehouse trucks doing the transport from production lines to buffer warehouse. Stefan Verbeken: ”It proved to be the most efficient solution, as well as the most cost effective.”
An investment request was filed, substantiated by a cost / benefit analysis. “The four weighing systems cost us approximately 16.000 Euro, but we also had to replace two older Yale trucks, since it would have been a waste of capital to build a scale into trucks that have only a few years left on their life cycle. Add 3.000 Euro for adjustments to Objective, the software that runs our production lines, and we ended up with 55.000 Euro as our initial investment. The benefits easily outweighed the costs. On daily inventories and packaging corrections alone we immediately saved one half FTE. Add to that: packaging on the correct order, less rest material, and fewer corrective casting runs. Approval came and Patrick Peeters set to work with IT and other departments involved.”
Patrick Peeters describes the resulting production process: “We now have four trucks with a weighing scale. Both the scale and the handheld on the truck communicate with Objective over our WLAN network. Once the semi-finished product comes off the line, it’s immediately weighed. The operator starts the protocol on his handheld: he enters the number of the production line and the article reference, and then triggers Objective to interrogate the scale for the weight. That completes the data set. From the handheld a barcode label is printed and the pallet is transported to the buffer warehouse.”
“On two of the three production lines the integration of the mobile weighing systems into Objective is now completed, the third line will soon follow”, says Patrick. “The nice thing about that is that we can compare the lines and see the results of the weighing systems: on the two integrated lines we now have only 50 kg of correction per month left, which is an extremely small amount compared to our monthly Tonnage. On the third line we still do daily follow-up and corrections. If we didn’t, we would have differences of up to 10 Tons on a monthly basis. RAVAS is helping us to limit daily corrections to a minimum.”
Stefan Verbeken: ”From Objective the data are imported into SAP. We now have real figures after Finishing, we can do yield analyses per product and from there optimize. We can steer by KPI’s. Packaging planning can be adjusted to the needs of the customer. With the RAVAS mobile weighing systems we have made a step forward in our production process.”