Shell Mould Casting

Iron and steel casting using the high tolerance Croning shell mould process.

Our onsite shell moulding facility is one of several casting processes available at Newby Foundries. We have 4 Polygram shell moulding machines, each with 2 stations so we can produce up to 8 different moulds concurrently.

Shell sand is produced in our purpose-built sand reclamation and recoating plant. The Polygram shell moulding machines then deposit resin coated sand onto the shell patterns which are pre-heated to 280°C. The heat causes the resin to bond the sand together forming a shell of sand on top of the pattern. Shell cores are produced in a similar way except the sand is blown into a heated corebox and ejected.

The strength provided by the resin bonding allows the production of high tolerance and dimensionally accurate iron and steel castings compared to other sand casting processes.  It also allows for more intricate, complex core assemblies to be produced and for the reproduction of a finer level of detail.

Our standard sand is silica, but we use cerabead sand for applications requiring low thermal expansion. This can eliminate issues such as veining and finning, and it is dimensionally very stable. An additional benefit is a lower resin demand - but it does come at an increased cost.

Whilst the most appropriate casting method for your project depends on its specifications, we recommend shell mould casting for medium to high volume runs of components up to 600 x 400mm.

Once shells are moulded, we have 3 main casting plants:

• Iron track – For iron castings up to 20kg
• Iron backing plant – For larger iron castings up to 100kg
• Steel track

Whether a new or existing product, our expert team will work with you to determine the most suitable casting method for your project.