Scotland mostly - through nsl4u

This foundry visit was a retro-visit for me having started out in 'metal
manufacturing' 36 years ago in Musselburgh, Midlothian.

The foundry does a wide assortment of products in 4 or 5 ''metal grades''
(cast steel, nodular iron, stainless steels, duplex steels, several other
exotic alloys...) in lost wax investment castings and also in green sand
castings.
The slides show from the wax 'pattern' of the product to be cast..the base
part and then glued onto the header box and gates....this then is taken
through a very precise and complex method of over coating with coarsening
grades of sand - all in a humidity controlled and circulating air
environment, absolutely critical to the quality of cast parts.
The moulds then have the wax ''lost'' form them as they then are prepared in
the furnace for accepting the poured metal; the wax all recovered and
re-used for ongoing moulding preparation.
The QC (quality control) is effected by tied samples (coupons) using
spectrograph (chemical elemental content), hardness testing, impact testing,
tensile testing and mirror polishing to check the grain under microscope.
All samples are marked with the unique cast id number and furthermore there
are often 'teaped' heat codes applied to all parts too - these all allow for
guarantee of traceability and the validity and goodness of the materials
made; fine adjustments are made to the ladle of metal before batch pouring
commences.

Moulds are put into the furnace for pre-heat as the hot ones are taken out
for pouring.
Handling is all manual at this very delicate stage and when set into the
metal baskets, the parts are allowed to cool prior to further handling
(mould breaking, and heat treatments as required...). Lost wax investment
casting gives superb consistency of parts and dimensional tolerancing and
overall 'cleanliness' of the cast parts (not too much 'fettling' required).

After the parts are split out of the moulds they progress through the shop;
there is inevitably a lot of handling and grinding, shearing, buffing,
sometimes some recovery welding (which require post-weld heat-treatments)
etc., etc ...so this aspect is noisy and dirty, as it has always been.
The interesting contrast is the slow moving, 're-freshing' canal just out
the back of the foundry...?!
Some foundries has trimming and clipping shops which use different
techniques, effectively to get the casting in a ''clean and handle-able''
state for acid pickling, rinse-washing, etc., ...thereafter for machining.

On the heavier side of the plant, there are the sand pattern boxes and both
sections of the moulds (pairs) can be seen - the rough as-cast parts can be
seen with all the split-line burrs and feed gate 'snots' etc ...and then
fettled parts can be seen in good condition looking like they ready to go
for acid pickling to overall clean up the as-cast surfaces.

In this visit the attitude and openness of the General manager and the
Operations manager was truly outstanding, and they can demonstrate an
excellent history of performance and a focus on quality of results.
The overall impression of 'the dark ages' in terms of working conditions is
actually not that far removed from our own shops just 20 years ago. The
Foundry have the pride of actually still doing honest casting work and
thereby supplying in to the manufacturing chain essential goods that have
world-wide demand. Ours is the pity that we did not find goodness and
necessity to maintain such shops, even though we might have aspired (and in
our remaining greatly depleted foundries do have) to considerably more
modern facilities and techniques. There is a space in the supply chain for
the right-cost and quality of goods..thus the Far East is feeding the global
economy with such engineered goods.

My compliments to Shining and Amy and their team for hosting a very
interesting and worthwhile visit.
Regards, Denis.