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11

This pattern is to provide sufficient strength while minimising the mass of the block. These "webs" are designed to prevent any vibration, if the block wall was made thin and the full length and width it would buckle or fail under the loads / stresses applied. This design allows the wall to be thin in-between the webs so reducing the mass and helping to ...


10

You need pattern draft to be able to remove the pattern from the sand before pouring. If you don't have any / sufficient draft then edges can be weakened or damaged / broken when you remove the pattern from the sand or plaster - whatever material it is. It is not to help remove the casting as the sand mould is destroyed.


7

Ductile iron is actually likely to expand during the casting process, as shown in the table found on the Casting Wikipeda page, which is in part cited from this casting text by Stefanescu. However, as the tables show, the range of volume change is fairly large and not one-sided, which is to say the ductile iron may either expand or contract depending on ...


6

these are part-tracking marks. they indicate which cavity in the mold the part was cast from, in which mold set, in what molding machine, in what year, month, day and shift. this way, a part that fails its finished goods inspection or failed in the field can be tracked backwards through the factory to its source, and the reason for the failure fixed.


4

According to p.33 of this presentation 'bedding in' is a process of packing the molding sand by ramming the sand around and under the pattern until the sand is tightly packed and even with the parting line. There is also a glossary with foundry and casting terms defined here. This is used when the parts to be cast are quite large, often as a step in pit ...


4

A riser is a static reserve volume of metal available to flow into the casting to compensate for shrinkage as the liquid freezes. Risers are relatively large because they should not freeze until after the casting has frozen. Risers may be "hot topped", exothermic material is put on to provide extra heat to keep the riser liquid as long as possible. ...


4

There are a couple of issues here. To get a proper fusion weld both surfaces need to melt and whether or not this happens depends on the details of the heat transfer for the whole system. It is certainly possible that heat could be conducted way from the interface too quickly for the surface to melt well enough to get good fusion. In this situation the ...


4

As mentioned in other answers these patterns are structural stiffeners to give strength to a lighter engine block. But they also have the task of distributing stresses due to internal vibrations of moving parts and concentrated stress of attached accessories such as exhaust manifold. That is a big help in increasing longevity of the entire engine ...


3

Extrusion and die casting are both fairly high volume processes which allow relatively rapid and cheap costs per item at the expense of high setup costs. Extrusion involves forcing a plastic material through a die, a bit like piping icing onto a cake this means that you are limited to producing prisms (in the geometric sense) ie a strip of arbitrary length ...


3

There are a number of approaches to this, depending on exactly what you want to achieve. There are dense castable refractories which will operate up to 1800C. For small quantities the best source is likely to be a ceramic kiln supplier. Industrial foundry supplier may have a wider range of products but tend to deal in larger quantities. Another possible ...


3

You can cast iron into cast iron moulds as long as the moulds have plenty of mass compared to the quantity of metal you are pouring into them. Small artisan foundries sometimes use cast iron moulds to make small ingots as a 'signature piece' to use up small quantities of surplus metal. Often these are open face moulds. Obviously steel works as well but ...


3

There are two closely related reasons. The first is that in terms of pure geometry webs tend to be more efficient in terms of strength and stiffness to weight ratios compared to a solid block of similar dimensions. You also see this a lot in fabricated and pressed structures. The second is that in castings it is generally desirable to keep section ...


3

Casting terminology can vary a bit. My experience is in art casting in cast iron. In my experience with sand casting risers specifically tend to be used as vents to allow gas to escape from the mould and tend to be small diameter and placed at high points. I'm more used to seeing the term well used in the context of feeding metal. There is no reason not ...


2

I am a metal casting process researcher who has several past and ongoing collaborations with commercial foundry and tooling experts. In commercial steel sand casting, I have observed the terms "riser" and "feeder" to be used more-or-less interchangeably. In the literature, British commonwealth authors tend to prefer feeder, while American authors tend to ...


2

Generally , no. That is more or less cold working , but the die prevents much strain , so very limited strain hardening / cold work. That could be called a "coining" operation. A special case could be a poor casting with gas porosity , shrinkage cracks or hot tears ; wherein the forging partially remedies some of these defects.


1

Copper with aluminum is called aluminum bronze in the trade; no zinc. Up to about 10% aluminum and a couple % iron . That system will get to about 300 BHN / Rc 30; a respectable hammer - not ductile. Manganese bronze is copper with 30 % zinc and a few % Al , Mn, and iron , also a very strong system for copper alloys . Copper Development Association will have ...


1

Redundant ; How would you pour with no gravity; the metal would just sit in the ladle after you turn it upside-down. Floating of slag/dross , and hydrogen gas ( always present to some degree) would not happen.


1

Looking up superconducting cables on the net , I doubt very much that any casting is involved ( to produce the final cables). The figures show multiple concentric tubes , some tubes to carry the cooling fluid and other tubes are the conductors and copper and insulation... If it was necessary to combine the copper and conductor into a single tube ( in the ...


1

It appears that NASA has been conducting experiments with 3D printing in space since about 2014. Around this time is when a 3D printer was sent to the space station. So while this doesn't necessarily answer your question, it should help you to understand that this is current research. This means that there might not be a lot of other information available. ...


1

Historically production was : ingot > reheat> bloom > reheat > billet. For about the last 40 years production has been : continuous casting directly produces billets. An ingot was roughly 2 ' X 4' X 8 ' . Continuous strands can be down to about 6 " X very long. There are a great number of variations depending on final product , alloy, the individual mill , ...


1

A company I worked at used tool steel molds and channels in the mold with flowing water to increase cooling. Heed the advice of others, never let ANY water come into contact with molten aluminum. I have seen it hit a 20' ceiling (would have gone farther) and as far as 15' in circumference.


1

A very home-spun option that should work would be to use a piece of tubing of a diameter to suit your purpose. Seamless steel tubing is available particularly on Aircraft Spruce and Specialty in many different diameters and wall thicknesses. The temperature coefficient of steel compared to aluminum (11 to 12.5 versus 8.1)is sufficient to allow you to pour ...


1

When I was a boy; We made a eight shapes ( as I remember) of parts like that for Ritter. They were produced by investment casting using 17 - 4 PH. There was a die witness line that carried over from the plastic pattern; it was polished away during tumble polishing. Medical equipment also uses 440 A, B and C for cutting tools. Vitalium may still have some use ...


1

Solid graphite is used. Simple shapes that are cut into the graphite. like wheels.


1

As a cast part, there should be at least two pieces that form the mold. There should be parting line between these pieces. Dimensions on one side of the parting line would be considered outside dimensions while dimensions on the other side would e considered inside. If the parting line is not specified on the print, then it could indeed be ambiguous as the ...


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