Difference Between Cast and Malleable Iron

The owners of Architectural Ironmongery Ltd would like to
explain the difference between malleable iron and cast iron
ironmongery. The products we sell from Kirkpatrick are all
malleable. We feel that we need to explain this due to the
cheaper cast iron products that are now are arriving in the
country, many of which are identical in size, shape and general
appearance. The difference is that cast iron will break.

The name Kirkpatrick Ltd has been synonymous with the production
of high quality malleable iron builders's ironmongery for over
140 years. At Architectural Ironmongery Ltd we keep an extensive
range of their Black Antique and Plain Gothic styles, all can be
seen on our website at http://www.arciron.com and available by
mail order.

Kirkpatrick's malleable iron products are hand-made in the their
foundry in Walsall using greensand casting process. At this
stage the castings are hard and brittle and cannot be hammered,
so they are subjected to a heat treatment known as 'annealing'.
In this process the castings are surrounded by an inert
haematite ore within iron drums and loaded into ovens of six to
eight tons capacity. The ovens take about two days to reach the
annealing temperatue of 980 C. The castings are then soaked at
this temperature for around 80 hours, after which they are
allowed to cool naturally. During this process the carbon
structure of the iron is changed. The resulting castings are no
longer hard and brittle, but soft and malleable.

After shot blasting and grinding to remove any rough edges the
castings are then assembled into finished or semi-finished
products. Following assembly a rust proofing finish may be
applied and a two-coat paint process is carried out, before
being passed for final inspection.

By choosing Kirpatrick malleable iron products you can be
confident that you are getting a product which is both
functional and highly decorative and one that, well maintained,
will give many years of service and pleasure