What are the functions of the lost foam coating

With the continuous development of the foundry industry, the most popular casting process used by Chinese foundry manufacturers in 2017 is lost foam and sand casting. Generally, manufacturers of single large-volume precision castings generally adopt the lost foam casting method, which mainly undertakes outsourcing and zero-lived foundry manufacturers. Most lost foam and sand casting are in use. Let’s summarize the advantages of the lost foam and sand casting.

According to the comparison between sand casting and lost foam production process, the lost foam has eight advantages over sand casting: wide production range and high precision standard. Suitable casting castings can reduce running cost, short cleaning time, suitable for mechanized production, and workers can find Easy to organize production quickly, high pouring efficiency and high customer satisfaction!

Since the molding materials used for sand casting are cheap and easy to obtain, the castings are easy to manufacture, and can be adapted to single-piece production, batch production and mass production of castings. For a long time, it has been the basic process in casting production. Sand casting is used to produce “a variety of complex geometric shapes of metal parts. These parts can vary greatly in size and weight, from a few grams to a few tons. Some smaller sand castings include component gears, pulleys, crankshafts, Connecting rods. Larger applications include large equipment and heavy machinery base housings. Sand casting is also suitable for the production of automotive components such as engine blocks, engine cylinder heads, and gearboxes.

The lost foam casting is a model made of foam material. After painting the special coating, it is buried in the negative pressure sand box with dry sand. After the dry sand is compacted by vibration, the metal liquid is poured under negative pressure. Thus, a casting having no flash burr consistent with the foam model is obtained. The foam model vaporization disappeared during the casting process, so the image was called lost foam casting.

Lost Foam Casting (also known as solid casting) is a combination of a paraffin or foam model similar in shape to the shape of the casting into a model cluster. After brushing the refractory coating and drying it, it is buried in the dry quartz sand for vibration molding, under negative pressure. Under the pouring, the model is vaporized, the liquid metal occupies the position of the model, and a new casting method for forming a casting after solidification and cooling is formed.

The eight main advantages of lost foam and sand casting are detailed:

1, Wide production range

Lost foam casting does not require parting and lower cores, so it is especially suitable for box-type, shell-like castings, and bobbin-type castings with complex geometric shapes and difficult traditional casting.

2, high precision standard

High dimensional accuracy can be achieved and thin walls (ie 3mm) can be cast. Because of the lack of modeling, the lost foam casting directly adopts the “fusion” method, so the shape of the casting is consistent with the mold. It is not necessary to consider the factors in the sand casting shape, the casting I casting wrong box, the collapse of the box and other artificial castings.

3, suitable castings can reduce operating costs

Compared to conventional sand forming methods, complex castings, especially those requiring high dimensional accuracy and having a thin cross section, can be produced at very high cost.

4, short cleaning time

Lost foam casting has a high dimensional accuracy, and there are no parting lines or vent needles and cores, so burrs and machining can be minimized. Cleaning hours can be reduced by more than 80%.

5, suitable for mechanized production

Lost foam casting is not only suitable for large-volume castings, mechanized operation, but also for manual splicing models of small batches of products.

6, people are looking for easy to organize production quickly

Lost foam casting eliminates the molding process and eliminates the need for skilled stylists. After a short training period, you can become a skilled worker.

7, high pouring efficiency

Lost foam casting is suitable for group casting, and dry sand is easy to remove sand. In some materials, castings can also be used for residual heat treatment according to the application. Multiple castings can be combined in one mold to increase casting efficiency.

8, high customer satisfaction

Lost foam casting is not only suitable for small and medium-sized parts, but also suitable for large-scale castings, such as: machine bed, large-diameter pipe fittings, large-scale cold-punching modules, large-scale mining equipment parts, etc., because the model production cycle is short, the cost is low, and the production cycle is short. Therefore, it is especially well received.

Of course, in some cases, sand casting is still required for casting production, and specific problems should be analyzed. With the advancement of society, casting production is becoming more and more “scientific”, so as a founder, it is necessary to follow the pace of the times and continuously learn and improve the casting production technology.