Henkel is a global laundry, cosmetic and adhesives manufacturer. Tim Brown talks to Stuart Rowe, operations director at the company’s Hemel Hempstead plant, about the factory’s contribution to the company’s adhesive technologies group.
The Hemel Hempstead plant manufactures and distributes materials such as adhesives, solder materials and fluxes. Aside from production, the plant also acts as a European distribution hub for other materials such as mould compounds and other conductive adhesives, and is planning to further increase its distribution role.
The core product
With over 70 years experience manufacturing solder products at the site, the Hemel Hempstead plant began its operational activities as a manufacturer of solder wire.
However, solder paste, which is essentially a powdered metal solder suspended in a thick medium called flux, is now the primary product produced at the plant. The paste, marketed under the name Multicore, is a grey viscous material used to make connections on a printed circuit board. “Components on a circuit board are getting smaller and require much smaller amounts of solder,” says Rowe. “The solution to this issue has been to take the solder metal alloy, atomise it into a powder and mix it with the flux.
The resulting product can then easily and accurately be applied to a circuit board.” Both virgin and recycled materials are used to form the appropriate alloys needed for the solder powder. Henkel obtains their virgin tin from a company called Wild Shore, and recycled materials both from their internal recovery processes and also from a company called Fenix. The alloy is blended and atomised in to the powder, which makes up approximately 90% of the required material. The remaining 10% is made up of the flux medium, which cleans the metal connections and also provides the paste with right rheological properties so it can be precisely applied to the circuit board.
Solder paste is generally applied to a circuit board in one of two ways.
A screen printing technique can be used where the paste is squeezed through a screen on to the circuit board, similar to screen printing a t-shirt. The other commonly used technique is to apply the paste using a syringe which dispenses the material directly on to the circuit board. As a result, the Multicore paste is sold in either a 500g pot for use in the printing process or in a cartridge for direct application.
Process changes
The Hemel Hempstead plant has actively engaged a set of continuous improvement initiatives in the manufacture of its solder paste. Starting the improvement process with the implementation of 5S, Rowe says the first step was to “remove anything superfluous to our operation while also ensuring that all operational necessities are well organised and identified.” Aiming to further improve the efficient operation of the plant, particularly as sales volumes are likely to increase during the course of this year, the plant has also greatly increased its use of lean techniques. “We are now pulling the material through the system as opposed to pushing it, ensuring that inventory is not building up at any one place,” says Rowe. “By equalising the different steps in the process, we have developed a one piece flow through the system, which is very effective.” In addition, Rowe says that due to it being established as a hindrance to smooth operational flow, the quality control element of the manufacturing process is being re-designed. “Part of our quality testing at the moment requires us to wait for 24 hours before we can confirm some of the tests on the solder paste. We are looking to see if we can do some of the critical tests more quickly so we can mix the paste and pack it straight away. The other tests can then be done in parallel while we are still packing the paste.” Packaging has been another area of focus for the company. Both a streamlining of the workload relating to packaging as well as the packaging itself has been undertaken. Traditionally, packaging was prepared with labels and caps well before it was required to be filled. “The idea of lean,” says Rowe, “is that we should only do that as a part of the process when you are going to need it. We are in the process of implementing that methodology. This means we are not building up large inventories of prepared materials well before we need them.” In addition, the company is aiming to further minimise any unnecessary packaging stock by introducing multilanguage labels. Multicore solder paste requires the display of safety information in the language local to the consumer. While the solder paste packaging does not provide a large amount of space for information display, the company is current working on a producing a single label capable of displaying the required information in 20 different languages. This will allow the company to greatly reduce both packaging label stocks and while minimising the excess production of paste for certain geographical markets.
Moving ahead
Clearly, considerable improvements have already been implemented at the Henkel Hemel Hempstead plant, with equally impressive enhancements in the pipeline. The plant’s plans to reduce excess stock and remove unnecessary processes are commendable, and likely to make a considerable difference to the profitability and performance of the plant. Indeed, through these process improvements the Hemel Hempstead plant plans to decrease its production lead time for production from four weeks to three and ultimately two, a target that Rowe says is “completely feasible”. Such progress bodes well for the future of Henkel, and in particular the Hemel Hempstead plant, as it continues to produce an important and class leading product for the technology industry.
