Difference Between Cast and Malleable IronWritten by Ali Arnold
The owners of Architectural Ironmongery Ltd would like to explain 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 cheaper cast iron products that are now are arriving in 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 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 their foundry in Walsall using greensand casting process. At this stage castings are hard and brittle and cannot be hammered, so they are subjected to a heat treatment known as 'annealing'. In this process 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 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 carbon structure of iron is changed. The resulting castings are no longer hard and brittle, but soft and malleable.
| | Concrete Cutting: The Unknown NicheWritten by Robert Short / Affordable Concrete Cutting
What is Concrete Cutting? Concrete cutting is a process of controlled sawing, drilling and removal of concrete performed by skilled operators using special saws that use diamond impregnated blades. Unlike old- fashioned dusty "jack hammer" method, modern concrete cutting leaves a smooth attractive finish and utilizes water so as not to create any dust or mess. There are many different kinds of concrete cutting but most common are wall sawing, core drilling and slab or flat sawing.Wall Sawing is process of cutting openings such as doors or windows in concrete walls, usually no more than 12" thick but in some cases up to 24" thick. This is accomplished by using a saw that attaches to a track on wall to be cut. This process utilizes an enormous 30" or even larger diameter diamond blade that can cut 12" or more of concrete all of way through from one side. This aspect of our business requires most skill and cannot easily be done by your average "do it yourselfer." As stated, wall sawing may entail cutting openings in concrete foundations but may also include lowering a foundation elevation, entire foundation removal and also cutting of concrete retaining walls in part or in whole. This type of concrete cutting requires skill and experience to cut perfectly smooth plumb and level openings with virtually no dust or mess, so it is a rather expensive service. Most concrete cutting companies charge a minimum of $425 just to take their equipment to a site and cut. Homeowners that build additions on to their home that have basements or cellars commonly find they need to cut into their existing concrete foundation to add an entry or passage between new and existing basements. It is much easier and in most cases less expensive to have this service performed during construction process and not after. Core Drilling is process of drilling perfectly round holes through concrete walls and floors. The diameters of holes range from 1" to 12" round but average 5" for most homeowner applications. In commercial applications core holes can range anywhere up to 60" round and more. Core holes are used for "utility penetrations" such as electrical, plumbing and heating but are also commonly used for venting furnaces or clothes dryers. Although not recommended, core drilling can be performed by an advanced "do it yourselfer" and equipment necessary to perform core drilling is readily available at your local tool rental and supply store. Most companies have a minimum charge of $250 to core a hole for you and it can take a professional as little as 10 minutes to unload his equipment, core hole, and reload his equipment. Yet, I have seen homeowners rent equipment and spend an entire weekend trying to core a single hole and then call a professional to complete project. Just like with any trade a professional concrete cutter will make his job look easy.
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