molding technology

Casting in sand mold casting is a method of long tradition and today still widely used. Mold only be cast once (and only once poured through the mold). The material is mainly sand, additives can come create separate names for each method separately. Here is the sand casting method


 Sand composition:
+ Cat: is a major component SiO2
+ Clay: mAl2O3 + + qH2O nSiO2
+ Adhesives: are those included in the mixture to increase the viscosity, durability, stick the particles together. Often used vegetable oil, sugar, cement, mixed with sand, binders, additives, additives increased porosity (sawdust, straw ..).
+ Mold coating: coating the surface of the increase surface gloss and heat resistance and heat resistance.
   Molds are made with intestines (if any) through the life of the sand (compacted), along with samples. After compaction, samples were withdrawn, leaving gaps - the shape of the casting is needed fabrication. After pouring metal into molds, freeze, and demolition to obtain castings.
   Today, new technology is product is made form polyestero fire. When pouring metal into molds to fire and metal to fill the mold.
 + The advantage is that large molded parts, complicated by bowel can do.
 + Sand mold casting Cons that have low accuracy, poor surface quality, low productivity, require qualified workers ingenuity, from the stage of molding, the intestine, the metal poured into the mold.
  Therefore, molding sand currently being used, but not exactly. This sometimes causes a few dozen kilograms great detail the exact requirements should still be molded metal .. In accordance with the production unit.
1. Fresh sand casting technology

Perhaps fresh sand was first used sand mold technology. Materials to make molds of sand clay water. Fresh sand is characterized by ease of use, the surface will be smooth castings if sand grain size small shirt. But due to the molding process need to beat to get the sample template, molded products will be highly redundant processing large. Fresh face particular line was automated as DISAMATIC line in Dong Anh Mechanical Company - fully automated

2. Technology framework

In the technology framework if fresh face in the kiln drying brings about 5am before pouring is also known as a dry campus

Here to introduce you to the technology of water glass sand hardened by carbon dioxide. Water glass, also known as sodium silicate solution was mixed before grinding into sand molds. Once the mold is complete, leave the mold spray solid carbon dioxide to leave. This is due to a chemical reaction between sodium silicate and carbon dioxide and water (the reaction between acid and alkaline) the water glass sand mold technology easy to do, easy to use products with less redundant processing, molding solid has been widely used in most molding companies across the country. Only downside is recycled sand problem is to note

3. Fire pattern technology

This is based on new technology than traditional methods. To cast one product, we need to manufacture such products by polyesteron, then poured into the mold and dry sand in combination with the vacuum, the mold will be robust. When pouring metal into molds Polyesteron will fire and liquid metal fills the mold (can easily reference the actual factory Hanoi Engineering, Institute of Technology 25 Vu Ngoc Phan)

4. Plastic sand molding technology

This is new technology for sand processing plant has 1 layer of plastic wrap. When bringing sand to produce formaldehyde acid, would be cold curing resin sand, or sand will be brought heated sand hot curing resin

5. Furan Technology

This is the line technology that Japanese companies will be preferred because of sand mixed with acid and furan resin, the mold will be hardened very good product, but the glossy surface is difficult issues environmental pollution Working for Furan is toxic plastic smell

Above is a method of molding sand relatively common. Besides, can not the methods listed special properties that have been studied and applied, will introduce to you in the post.


The process of molding sand - clay (by hand).
Sand casting process is shown in the visualization so that you easy to imagine.

1. Put half of mold box

2. Create sand layer jacket for easy sampling

3: Create a buffer layer of sand around the pattern (this layer mixed with sand molds with high fineness of castings for easy printing)

4. sand Lagoon

5. Brushing off the excess sand

6. Turn mold


7. Assemble the remaining half of mold (Note cotter)

8. Positioning system of liquid metal (filling system, hot tops) and exhaust (question mark)