As one of the first foundries to take advantage of large-scale 3-D sand printing technology, the AMRC Castings Group has recently enhanced both its capacity and physical envelope.

Capable of producing complex moulds and cores for oil, gas, aerospace and automotive without the need for dedicated tooling, this technology has been used for R&D, pre-production and full-scale production volumes at the University of Sheffield’s Advanced Manufacturing Research Centre (AMRC) (www.amrc.co.uk).

AMRC Castings (part of the AMRC, based on the Advanced Manufacturing Park at Catcliffe) now has two additive-manufacturing machines for the 3-D printing of one-piece 3-D sand moulds and complex cores that would ordinarily require a significant investment in pattern equipment and multiple core-boxes.

The ExOne S15 digital mould and core making system has recently been upgraded to incorporate an advanced operating system that increases its speed.

It has also been modified to run on 100% Cerabeads artificial sand — suited to higher-temperature alloys — and now has a build envelope of 1,500 x 750 x 750mm.

Its sister printer — the ExOne Smax — produces complex sand cores and moulds in silica sand, which is more suitable for aluminium and cast-iron alloys. It also benefits from a larger build envelope of 1,800 x 1,000 x 700 and two ‘palletised’ job boxes, which allow rapid set-ups outside the printing process (and therefore reduced lead times).

The AMRC Castings Group’s Anthony Kenney said: “As before, both machines produce 3-D sand-printed moulds and cores for use in the foundry industry.

“However, due to further investment in process enhancements, we have been able to increase capacity and accuracy — and further reduce lead times.

“Regardless of size, moulds and cores can be made with an accuracy of ±0.3mm; and depending on the print density, the typical turnround time is 12-24hr for the SMax and 24-50hr for the S15.”