KMG Gloucester Composites is a boutique manufacturer of SMC compounds. We specialise in the manufacture of custom designed materials for specific applications. KMG Gloucester Composites manufactures UV curing materials, special grades of fire retardant materials, and both low and high conductivity materials. Due to our vast experiencing in mouldings we can design materials to suit particular products and mouldings.
The process used for making the SMC is illustrated below:
All ingredients, except the glass, are mixed together to form a resin paste. This paste is
then transferred to a doctor box, which deposits it onto a moving carrier film passing directly
beneath.
Simultaneously, glass fibre rovings are fed into a rotary cutter above the resin covered carrier
film. The glass fibres are chopped to the required length and then dropped onto the resin paste,
as shown below.
The glass fibres are deposited randomly, but generally orient themselves slightly parallel to
direction of film travel. The amount of glass is controlled by the speed of the carrier film.
Downstream from the chopping operation, a second carrier film is coated with resin paste and laid
resin side down, on top of the chopped glass fibres already deposited on the first film. This
stage of the process creates a resin paste and glass fibre "sandwich" which is then sent through
a series of compaction rollers where the glass fibres are wet out with the resin paste and the
excess trapped are is squeezed out of the sheet.
At the end of the compaction rollers the SMC has been transformed from its liquid, fibre & powdered
ingredients into a sheet product that is usually about 4mm thick & 1500mm wide.
SMC continues to thicken after manufacture and therefore has a limited shelf life. Usually SMC
must be used within weeks or several months from the date of manufacture. This time frame can
be extended or reduced depending on the SMC formulation and storage conditions.