1. Precision casting can also be divided into gravity casting and pressure casting according to the pouring process of molten metal. Gravity casting refers to the process of pouring molten metal into a mold under the action of the earth's gravity, also known as casting. Gravity casting in a broad sense includes sand casting, metal casting, investment casting, clay casting, etc.; gravity casting in a narrow sense refers to metal casting. Pressure casting refers to the process in which molten metal is injected into the mold under the action of other external forces (not including gravity). In a broad sense, pressure casting includes pressure casting, vacuum casting, low pressure casting, centrifugal casting and so on. Die casting in a narrow sense refers to die casting of metal molds by die casting machine, referred to as die casting. Chengmao Hardware Products Factory has long been engaged in the gravity casting of sand and metal molds. These casting processes are currently the most commonly used and the lowest relative prices in non-ferrous metal casting.
2. Sand casting is a traditional casting process that uses sand as the main molding material to make molds. Gravity casting is generally used for sand molds, and low-pressure casting and centrifugal casting can also be used when there are special requirements. Sand casting has wide adaptability and can be used in small blocks, large blocks, simple blocks, complex blocks, single pieces, and large quantities. The mold used for sand casting used to be wooden, called wooden mold. In order to overcome the shortcomings of wood molds such as easy deformation and damage, Chengmao Hardware Products Factory changed all sand molds to aluminum alloy molds or resin molds with high dimensional accuracy and long service life. Although the price has increased, it is still much cheaper than the mold used in permanent mold casting, especially in small batches and mass production. In addition, sand molds have higher fire resistance than metal molds, so materials with higher melting points, such as copper alloys and ferrous metals, also use this process. However, sand casting also has some shortcomings: since each sand mold can only be poured once, the mold must be reshaped after the casting is obtained, and the production efficiency of sand casting is low; because the sand is soft and porous as a whole, sand casting has low dimensional accuracy and rough surface. However, the technology accumulated by Chengmao Precision Foundry for many years has greatly improved the surface condition of sand castings, and the effect after shot peening is comparable to that of metal castings.
3. Lost foam casting is a modern technology that uses heat-resistant alloy steel to manufacture hollow molds. The metal mold can be cast by gravity or pressure. The metal mold can be used repeatedly, once the molten metal is poured, a casting is obtained, which has a long service life and high production efficiency. Metal castings not only have good dimensional accuracy and smooth surface, but also have higher strength than sand castings and are not easily damaged when the same molten metal is poured. Therefore, in the mass production of small and medium-sized non-ferrous metal castings, as long as the melting point of the casting material is not too high, metal casting is generally preferred. However, permanent mold casting also has some disadvantages: because the heat-resistant alloy steel and the cavity made on it are expensive, the metal mold is expensive, but the overall cost is much cheaper than the die casting mold. For small batch production, the mold cost allocated to each product is obviously too high, which is generally unacceptable. In addition, because the metal mold is limited by the size of the mold material and the capabilities of the cavity processing equipment and casting equipment, it seems that it can't do anything for particularly large castings. Therefore, in the production of small batches and large batches, permanent casting is rarely used. In addition, although the metal mold is made of heat-resistant alloy steel, the heat resistance capacity is still limited. It is generally used for casting aluminum alloy, zinc alloy, and magnesium alloy. It is used less in copper alloy casting and less used in ferrous metal casting. The metal molds of Xudong Precision Casting Factory are all designed and manufactured by ourselves, which can provide customers with cheap and suitable high-quality molds in time.
4. Die casting is a metal die casting process performed on a die casting machine, which is currently the most efficient casting process. Die casting machines are divided into two types: hot chamber die casting machines and cold chamber die casting machines. The hot chamber die casting machine has a higher degree of automation than the cold chamber die casting machine, with less material loss and higher production efficiency. However, due to the limitation of heat resistance of parts, it can only be used for casting production of low melting point materials such as zinc alloy and magnesium alloy. The aluminum alloy die castings that are widely used today can only be produced on cold chamber die casting machines due to their high melting point. The main feature of die casting is that molten metal fills the cavity under high pressure and high speed, and then forms and solidifies under high pressure. The disadvantage of die casting is that the air in the cavity is inevitably wrapped in the inside of the casting to form subcutaneous pores, so aluminum alloy die casting is not suitable for heat treatment, and zinc alloy die casting is not suitable for surface spraying (but painting). Otherwise, when the pores inside the casting are heated by the above treatment, the casting will be deformed or blistered due to thermal expansion. In addition, the machining allowance of die castings should be smaller, generally about 0.5mm, which can reduce the weight of the castings, reduce the processing volume and reduce costs, and avoid penetrating the surface dense layer, exposing subcutaneous pores, and causing the workpiece to be scrapped.
Dongguan Chengmao Hardware Products Co., Ltd. specializes in the production of stainless steel, carbon steel, low-alloy steel precision castings and their products, with an annual production capacity of 600 tons of castings. The company is located in Daojiao Town, Dongguan City, Guangdong Province, adjacent to the Wanjiang (Daojiao) exit of Guangzhou-Shenzhen Expressway, and is connected to the Dongguan West Express Line with convenient transportation.
We have the most professional engineering team to provide customers with the highest quality and most economical product design solutions. Mold manufacturing, precision casting, machining, surface treatment.