Precision investment Casting forkhead for slab construction formwork system

investment casting ledger end scaffolding accessories for scaffolding.
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Specifications:
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Description:
Investment casting is an industrial process based on and also called lost-wax casting, one of the oldest
known metal-forming techniques.From 5,000 years ago, when beeswax formed the pattern, to today’s high-technology waxes, refractory materials and specialist alloys, the castings allow the production of
components with accuracy, repeatability, versatility and integrity in a variety of metals and high-
performance alloys. Lost-foam casting is a modern form of investment casting that eliminates certain steps in the process.

There are a variety of materials that can be used for the investment casting process, including stainless
steel alloys, brass, aluminum, and carbon steel. The material is poured into a ceramic cavity designed to
create an exact duplicate of the desired part. Investment casting can reduce the need for secondary
machining by providing castings to shape.
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Casts can be made of the wax model itself, the direct method; or of a wax copy of a model that need not be?of wax, the indirect method. The following steps are for the indirect process which can take two days to one?week to complete.

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Produce a master pattern: An artist or mould-maker creates an original pattern from wax, clay, wood,
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plastic, steel, or another material.
Mouldmaking: A mould, known as the master die, is made of the master pattern. The master pattern may
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be made from a low-melting-point metal, steel, or wood. If a steel pattern was created then a low-melting-
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point metal may be cast directly from the master pattern. Rubber moulds can also be cast directly from the
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master pattern. The first step may also be skipped if the master die is machined directly into steel.
Produce the wax patterns: Although called a wax pattern, pattern materials also include plastic and frozen
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mercury. Wax patterns may be produced in one of two ways. In one process the wax is poured into the
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mold and swished around until an even coating, usually about 3 mm (0.12 in) thick, covers the inner surface
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of the mould. This is repeated until the desired thickness is reached. Another method is filling the entire
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mould with molten wax, and let it cool, until a desired thickness has set on the surface of the mould. After
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this the rest of the wax is poured out again, the mould is turned upside down and the wax layer is left to
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cool and harden. With this method it is more difficult to control the overall thickness of the wax layer.
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If a core is required, there are two options: soluble wax or ceramic. Soluble wax cores are designed to melt
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out of the investment coating with the rest of the wax pattern, whereas ceramic cores remain part of the
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wax pattern and are removed after the workpiece is cast.
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Assemble the wax patterns: The wax pattern is then removed from the mould. Depending on the
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application multiple wax patterns may be created so that they can all be cast at once. In other applications,
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multiple different wax patterns may be created and then assembled into one complex pattern. In the first
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case the multiple patterns are attached to a wax sprue, with the result known as a pattern cluster, or tree;
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as many as several hundred patterns may be assembled into a tree. Foundries often use registration marks
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to indicate exactly where they go.The wax patterns are attached to the sprue or each other by means of a
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heated metal tool.The wax pattern may also be chased, which means the parting line or flashing are rubbed
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out using the heated metal tool. Finally it is dressed, which means any other imperfections are addressed
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so that the wax now looks like the finished piece.
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Investment: The ceramic mould, known as the investment, is produced by three repeating steps: coating,
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stuccoing, and hardening. The first step involves dipping the cluster into a slurry of fine refractory material
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and then letting any excess drain off, so a uniform surface is produced. This fine material is used first to
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give a smooth surface finish and reproduce fine details. In the second step, the cluster is stuccoed with a
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