Sheet Moulding Compound (SMC)

Amlites Composite Cover and Drainage Grates are manufactured from a material called Sheet Moulding Compound – SMC.

What is (SMC)?

SMC is a high strength glass fibre reinforced thermoset, moulding material which is normally compression moulded using heated mould tools under high pressure on a large press.

SMC combines glass fibre and unsaturated polyester/ phenolic/Vinyl and Acrylic modified resins, fillers (Calcium carbonate), catalysts, pigments and stabilizers and release agents to produce a high strength moulding compound.

The manufacture of SMC is a continuous in-line process. The material is sheathed both top and bottom with a polyethylene or nylon plastic film to prevent auto-adhesion. The liquid material is spread uniformly onto the bottom film. Chopped glass fibres are deposited onto the mixture, the top film is introduced and the sandwich is rolled into a pre-determined thickness. The formed SMC material is allowed to cure for 48 hours.

Once cured the material can be used for manufacture where it is placed as cut layers into the pre heated Amlite moulds and compressed at a set tonnage and time suitable for the size and load rating of the cover.

Why use SMC?

SMC is an ideal material for composite manhole covers due to its high strength-to-weight ratio resulting in a similar strength to a steel cover but with a significant drop in overall weight. Using SMC Amlite is able to produce composite covers to exceed 400kn Load when required in line with the most recent European Standard EN124-2015.

Features and Benefits of SMC

Chemical Resistance
SMC material has good chemical resistance (salts, fuels etc). SMC manhole covers will never go rusty!

Antistatic
Excellent antistatic properties allows safe use in potentially hazardous environments such as Fuel Stations and Chemical Plants.

Performance in extreme temperatures
SMC manhole covers are used in installations across the globe in both cold and hot environments without effecting the performance of the covers. SMC has a low thermal expansion coefficient so is unaffected by temperature changes.