Drying and curing seminar

Citation

(1999), "Drying and curing seminar", Pigment & Resin Technology, Vol. 28 No. 2. https://doi.org/10.1108/prt.1999.12928bac.001

Drying and curing seminar

Drying and curing seminar

Keywords Curing, Drying, East Midlands Electricity

The latest in a series of one-day seminars organised by East Midlands Electricity covered various aspects of drying and curing and proved to be one of the most successful events held at the company's Technology Demonstration Centre, in Wollaton, Nottingham. The seminar attracted around 200 delegates from all over the East Midlands region and consisted of four morning presentations, accompanied by a series of demonstrations of drying and curing in action by equipment manufacturers.

The event was chaired by Bryan Buffham, professor of chemical engineering at Loughborough University and the individual presentations covered the basic principles of drying and curing, the range of technologies available and examples of these technologies in practice.

The first presentation, by Dr Peter Mynott, of Electronic Control Services, explained the basic principles of drying by examining the problem of drying a pair of socks. He stressed the importance of defining the initial wetness and desired dryness of any product to be dried. He then went on to explain the mechanisms involved in the sock drying process, which he listed as mechanical force, exposure to air, air movement and heat. Using this as a platform he then developed each of these mechanisms to describe drying technology such as air knives, dehumidification, convection ovens, infrared heating and dielectric heating. He summarised by stating that it is always important to set drying targets and then investigate the techniques available to meet these targets quickly, efficiently and at minimum cost.

The principles of curing paints and lacquers were elaborated by the next speaker, Graham Armstrong, of Gama Sales and Marketing Services. He set out the basic constituents of paints and then went on to describe the three main drying mechanisms:

1. 1.

   solvent evaporation;

2. 2.

   oxidation; and

3. 3.

   polymerisation/cross linking.

He explained how catalysts were used to initiate and speed up the polymerisation process, both in terms of two-pack systems and in terms of paints which use heat as an external catalyst. He then elaborated on the use of radiation curing, specifically infrared and ultraviolet systems.

Drying and curing installations in practice were discussed by the two final speakers. Ian Lewin of East Midlands Electricity explained how dehumidification had been the answer to a hat manufacturer's drying problems before going on to describe how a combination of air knife technology and infrared heating had allowed the same manufacturer to dry a waterbased glue used to stiffen banana skin mesh, a material very much in vogue in the hatmaking industry. He then explained how East Midlands Electricity had been involved in the extensive trialling of various techniques to dry moulds used in the manufacture of turbine blades before recommending that a convection oven represented the optimum technology. He also described how two short wave infrared ovens had helped a manufacture of plastic automotive components to make a successful transition from solvent-based metallic paints to environmentally friendly, water-based alternatives. A feature of this particular project was the close working relationship established between the component manufacturer, the paint manufacturer, the equipment supplier and East Midlands Electricity.

After describing another infrared installation, where a low-cost medium wave unit had helped a manufacturer of stained glass casement windows to eliminate production bottlenecks and reduce fuel costs, Ian concluded by listing the range of benefits which could be realised by users of electric drying and curing technologies. He pointed out that his company's Technology Demonstration Centre was freely available to assess the merits of alternative technologies, to carry out feasibility studies, to perform pre-production trials and to provide advice and assistance.

Infrared, and the value of assistance from East Midlands Electricity, was very much the theme of the last speaker, Peter Redhead of Mayflower Vehicle Systems plc the international engineering and manufacturing group and the world's second largest supplier of skin panels for the automotive industry. Peter described a number of projects which had been carried out at the company's Coventry site with significant input from East Midlands Electricity. These ranged from curing seam sealant prior to surface painting to pre-heating sound absorption panels to facilitate fitting and improve the adhesive properties.

Details are available from East Midlands Electricity, Woolsthorpe Close, Bilborough, Nottingham NG8 3JP.