What all should you know about Pump Casting?

Pump casting refers to creating to creating high-quality casting such as steel casting, aluminium casting and iron casting to get precision, strength, ductility, high resistance properties and a good surface finish. It is generally used in petrochemical industries, oil extraction industries, water plant industries, fire control system, irrigation, air conditioning, desalination, chemical, nuclear and waste industries, cooling and circulation of applications. The common materials used are nickel based alloy, super duplex stainless steel, and heat-resistant stainless steel, steel and iron. Though there are various methods for pump parts casting, manufacturers may also go for CNC machine and NC lathe for machinery.

1. Pump casting manufacturing process
There are a wide range of methods to make the components of pump and valve casting. Two of the common casting methods are non-ferrous and ferrous methods –

a) Ferrous casting
Casting of pumps can be done by flexible iron casting, ductile iron casting and gray iron casting. All of these metals impart a special quality to the metal –

Flexible iron casting gives an outstanding surface finish, good machinability, and good control of dimensions and freedom of design.

Grey iron casting gives an excellent machining, compressive strength, dampening capacity and good resistance to wear and tear.

Ductile iron casting gives high tensile strength, easy feeding of difficult design, good machinability and a lesser amount of deflection when load is applied.

b) Non-ferrous casting
Non-ferrous pump casting methods include –

Silicon brass coating, which minimises contamination through lead.

Red brass coating, giving good machining qualities.

Alloy of Tin and Bronze, which is used in valves that handle steam at high temperatures of 55 degrees Fahrenheit, and subject to medium pressure.

A 356.0 Primary and 356.0 Secondary, which give pressure tightness, corrosion resistance and good machinability.

2. Types of pump casting

There are different kinds of pump, each of which are ideal for their specific jobs –

a) Single Volute Pump
The most common type of pumps, their simplicity makes it more economical to manufacture and open designs allows for longer breaks between required maintenance repair. Single volute pumps are best for applications that require large waste material handling. They have a best efficient point where the pump shifts the most amount of material having a steady flow of material feeding the pump. Any slip up could radiate the load deflects on the pump shaft and cause excessive wearing of rings, seal and bearings. One can maximise the pump’s mechanical life by using a single volute pump.

b) Double volute pump
A double volute pump is necessary where there is no steady flow of material feeding the pump. The design is similar to a single volute pump, but has an additional divider or splitter vane that separates the material inflow into two equal streams. The divider allows one stream to enter the pump at the opposite end from the original inflow. This distributes the radial thrust, which are then used against each other for neutralisation. Thus, a splitter vane helps restrict the amount of waste material that can be pumped.

3. Modifications in the pump casting industry
John H. Me-Gowen, of Cincinnati, Ohio is accredited to have brought out a new invention regarding pump casting. Already described in the journal, the Scientific American, the modern method of casting makes the overall process much easier. This is done by mounding up the top of the “knowl” of the cores in the interiors of the pump. This will help all the cores in position when the metal is poured in.

The right knowledge of pump parts casting, knowing their types and benefits is essential. This is why we need to look for a reliable pump casting manufacturing company to have the best quality at reasonable manufacturing costs and the best technology.

The science behind the non-rust stainless steel castings

Stainless steel has been a household name for years now. So many things make use of stainless steel, from daily usage items such as spoons and knives to more important things like parts of a machine.

What is it?
Stainless steel as you all must already know, is actually an alloy. Manufactured in a stainless steel foundry it is an alloy of iron containing parts of manganese, chromium, silicon and carbon. Sometimes stainless steel is manufactured by adding nickel and molybdenum to it. Stainless steel since its inception had become an indispensable item both in the factories and in regular use owing to the fact that unlike iron or other metals, it seems to be immune to the degrading effects of oxygen and the atmosphere. Iron when used for long, is likely to rust and start crumbling. Stainless steel, however, is capable of withstanding these natural elements and can be used for years without any signs of tarnish or rust on it.

This property of stainless steel along with the fact that it looks good, and is light weight has contributed to its usage in so many things.
Why does it not rust?

This has been a matter of extensive research ever since stainless steel has been manufactured in stainless steel foundry as an alloy and its special property discovered. Other alloys of iron, are susceptible to the same dangers as iron is, so let us see what makes stainless steel so resistant.

1. The special alloy stainless steel, remains stainless because of the chemical reaction that happens as its components and the atmosphere come in contact. The components of this alloy such as chromium when they react with the oxygen that it might get from water or the air, lead to the formation of a protective layer, something like a very thing coating. This film that is formed is a pretty stable layer and it contains products like oxides and hydroxides of metals. The main element that plays the protector is chromium. All stainless steel contains at least 10% chromium, which helps form the film.

2. Once this film is formed, it prevents the water or air from causing any harm to the underlying alloy. The first attack of atmospheric elements is enough to form the layer and it stays tight and fine on the surface negating the rusting effects. However, we can't actually see this film, because it is absolutely thin, thinner than the wavelength of light. Scientists can see this film once they all their modern gadgets.

3. So technically the steel is getting corroded at its atomic level but we can't see it, and thus the stainless steel products remain stainless. It is very different from normal steel where the layer of corrosion formed is thickened with time and you see a whitish deposit over your steel item. That is the rust, which is very much viable to the naked eye.

There are other metals too which do not rust because of the same reason, like aluminium or titanium. They too form a film that prevents corrosion. Stainless steel, on the other hand, is way cheaper and it has an aesthetic appeal. So you get rust free, aesthetic and durable all in one when you use stainless steel products