Properties of metals

The cutting performance of metal includes: ① fluidity, the ability of liquid metal to fill the mold; ② shrinkage tendency, large volume shrinkage from liquid to solid, easy to produce defects such as shrinkage cavity, and large linear dimensional shrinkage, which affects the final dimensional accuracy of castings; ③ hot cracking tendency, some metals and alloys are prone to cracks and segregation tendency in the cutting process.

Handling and Inspection

Mold (liquid metal into a solid casting container) preparation, mold according to the materials used can be divided into sand, metal, ceramic, mud, graphite, etc., according to the number of use can be divided into one-time, semi-permanent and permanent, mold preparation is the main factor affecting the quality of castings

Machining allowance

Gravity cutting It is widely used in the production of various non-ferrous castings, but metal mold cutting also has the disadvantages of low metal utilization rate, difficult pouring of thin-walled complex castings, and low relative pressure cutting of casting tissue density.

When using metal type cutting, the following factors must be considered

When using metal type cutting, the following factors must be considered comprehensively: long manufacturing cycle, high cost, not suitable for single-piece and small-batch production; It is not suitable for cutting complex shapes (especially inner cavities), thin-walled and large castings (metal molds are limited by the size of mold materials and the ability of cavity processing equipment and cutting equipment, so metal molds are not suitable for the production of particularly large castings). The mold is more expensive than sand mold and cheaper than die casting.

The adaptability of sand cutting is very wide

Sand cutting mold, general wood production, commonly known as wood mold. In order to improve the dimensional accuracy is higher, but also often use a longer life of aluminum alloy mold or resin mold. Although the price has increased, but still much cheaper than the metal cutting mold, in the small batch and large production, the price advantage is particularly prominent. Metal Type Cutting

Metal Cutting Applications

Sand cutting adaptability is very wide, small pieces, large pieces, simple pieces, complex pieces, single pieces, large quantities can be used. Sand mold is more refractory than metal mold, so materials with higher melting points such as copper alloys and ferrous metals are also used in this process.

Classification of metal cutting

Metal cutting types modeling methods are customarily divided: ① ordinary sand type cutting, including wet sand type, dry sand type and chemical hardening sand type 3. ② Special cutting, according to the molding material can be divided into natural mineral sand as the main molding material of special cutting (such as investment cutting, mud cutting, cutting workshop shell cutting, negative pressure cutting, solid cutting, ceramic cutting, etc.) and metal as the main casting material of special cutting (such as metal cutting, pressure cutting, continuous cutting, low pressure cutting, centrifugal cutting, etc.).

Metal Cutting History

In ancient times, China, India, Babylon, Egypt, Greece and Rome had cut weapons, sacrificial objects, works of art and household utensils. Early castings were made of gold, silver, copper and their alloys. The Bronze Age is a glorious page in the history of human civilization; later cast iron pieces appeared. Iron castings were widely used in China as early as the Warring States period, and the technical tradition has a long history. Metallurgy and cutting are complementary processes, and the term "metallurgy" in ancient China reflects this fact. Although the cutting process has developed into a relatively independent branch of the mechanical manufacturing process, it is still inseparable from the metallurgical process.

Metal cutting is to cut metal into shapes that meet certain requirements.

Metal cutting is to cut metal into shapes that meet certain requirements. Cutting blanks because of nearly forming, and to achieve the purpose of no machining or a small amount of processing to reduce the cost and reduce the time to a certain extent, cutting is one of the basic processes of modern machinery manufacturing industry.