CN204413050U - Die for testing melting degree of internal chill - Google Patents

Abstract

The utility model relates to a mold for testing the melting degree of inner cooling iron, which comprises a main body, which is rectangular, and a rectangular cavity is arranged inside the main body, and the bottom of the cavity communicates with the outside through a pouring channel arranged on one side of the cavity. The lower end of the pouring channel communicates with the mold cavity, and the upper end of the pouring channel is provided with a bell mouth. Inside the mold cavity, there are several steel rods arranged vertically and parallel. Inwardly, the distance between two adjacent steel rods is equal. The castings cast by the mold used to test the melting degree of the inner cooling iron can help to quickly and accurately test the relationship between the modulus of the inner cooling iron, the pouring temperature and the modulus of the casting, and then obtain the design method of the inner cooling iron, which can be more reasonable The internal cooling iron suitable for thick and large iron castings is designed and cast properly.

Description

Mold for testing the melting degree of internal cooling iron

technical field

The utility model relates to a mold used for testing the melting degree of inner cooling iron.

Background technique

In the casting process design of castings, chilled iron is used to accelerate the cooling rate of a certain part of the casting during the pouring process. Because of its structural requirements, the wall thickness of each part of the casting is uneven. Some parts are very thick and cool slowly during the cooling process, while parts with thin wall thickness cool quickly, which makes the cooling speed of each part of the same casting uneven. As a result, shrinkage cavities may occur, or the thin-walled parts may be cracked. In order to avoid this phenomenon, after the molding is completed, add cold iron to the part with thick wall, use it to absorb the temperature of molten metal, accelerate the cooling speed of this part, and shorten the cooling time difference with other parts with thin wall thickness . Whether it is simultaneous solidification control technology or sequential solidification control technology, chilled iron is widely used.

The chill iron is divided into inner chill iron and outer chill iron. The direct outer chill iron is placed outside the casting and is in direct contact with the casting. When the metal liquid is poured into the mold cavity, it directly contacts the chill iron and performs intense heat exchange. Rapid cooling, but for some thick and large castings, the solidification process of the castings cannot be controlled only by cooling with the external chiller, the cooling of the center of the casting is still slow, and the grains are coarse. The metal is placed in the mold. When the metal liquid enters the mold cavity, the metal liquid surrounds the inner cooling iron and exchanges heat with the inner cooling iron. The inner cooling iron is heated and the metal liquid cools. At the same time, the inner cooling iron A metallurgical reaction occurs between the surface and the metal liquid, and the surface of the inner cooling iron melts. When the metal liquid is completely solidified, the solidified structure of the metal liquid is combined with the inner cooling iron to form a complete casting. In order to meet the requirements of melting the surface of the inner cooling iron, the size, shape and quantity of the inner cooling iron need to be accurately calculated and designed. If the inner cooling iron is too small, it will be completely melted by the metal liquid during the pouring process, and the cooling effect of the metal liquid is small. If the inner cooling iron is too large, the metal liquid cannot melt the surface of the inner cooling iron, and an interface will be formed between the inner cooling iron and the casting, resulting in the scrapping of the casting. In terms of the design of the inner cooling iron, the design manual only gives the empirical data for the design of the cast steel inner cooling iron, and the calculation formula does not give strict conditions, such as the requirements for the composition of the inner cooling iron and the pouring temperature, which leads to the design of the inner cooling iron. Deviations often occur; as for the design of cast iron inner cooling iron, there is currently almost no relevant design information, and there is no more suitable mold structure for selection. Therefore, in the design of cast iron internal cooling iron, rational design and use of internal cooling iron has important theoretical value and practical guiding significance for the production of thick and large iron castings.

Utility model content

The technical problem to be solved by the utility model is to provide a mold for testing the melting degree of the inner cooling iron in order to overcome the deficiencies of the prior art.

The technical solution adopted by the utility model to solve the technical problem is: a mold for testing the degree of melting of the inner cooling iron, including a main body, the main body is rectangular, and the inside of the main body is provided with a rectangular cavity, and the cavity The bottom of the casting channel communicates with the outside through a pouring channel arranged on one side of the cavity. The lower end of the casting channel communicates with the cavity. , each steel bar is located in the vertical plane where the center line along the rectangular length direction of the bottom surface of the cavity is located, and the distance between two adjacent steel bars is equal.

Preferably, the length of the main body is 400mm, the width is 40mm, and the height is 300mm. There are 5 steel rods, and the diameters of the 5 steel rods are 5mm, 8mm, 10mm, 12mm and 15mm respectively. The spacing between the steel rods is 50mm.

Preferably, the steel rod is low carbon steel, medium carbon steel, high carbon steel or stainless steel.

The beneficial effect of the utility model is: the casting casted by the mold used for testing the melting degree of the inner cooling iron can help to quickly and accurately test the relationship between the modulus of the inner cooling iron and the pouring temperature and the modulus of the casting, and then obtain the inner cooling The iron design method can more rationally design and cast inner cooling iron suitable for thick and large iron castings.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described.

Fig. 1 is the structural representation of the mold that is used to test the melting degree of inner cooling iron of the present utility model;

In the figure: 1. Main body, 2. Cavity, 3. Steel rod, 4. Pouring channel.

Detailed ways

Now in conjunction with accompanying drawing, the utility model is described in further detail. These drawings are all simplified schematic diagrams, and only schematically illustrate the basic structure of the utility model, so they only show the configurations related to the utility model.

As shown in Figure 1, a mold for testing the melting degree of the inner cooling iron includes a main body 1, the main body 1 is rectangular, and the inside of the main body 1 is provided with a rectangular cavity 2, and the bottom of the cavity 2 passes through The pouring passage 4 arranged on one side of the cavity 2 communicates with the outside, the lower end of the pouring passage 4 communicates with the cavity 2, the upper end of the pouring passage 4 is provided with a bell mouth, and the interior of the cavity 2 is provided with several vertically parallel Each steel rod 3 is located in the vertical plane where the centerline along the rectangular length direction of the bottom surface of the cavity 2 is located, and the distance between two adjacent steel rods 3 is equal.

As preferably, the length of the main body 1 is 400mm, the width is 40mm, and the height is 300mm. There are five steel rods 3, and the diameters of the five steel rods 3 are respectively 5mm, 8mm, 10mm, 12mm and 15mm. The spacing between the two steel rods 3 is 50mm.

Preferably, the steel rod 3 is made of low carbon steel, medium carbon steel, high carbon steel or stainless steel.

Each steel bar 3 is a steel bar 3 after shot peening treatment; shot peening treatment is also called shot peening strengthening, which is one of the effective methods to reduce fatigue of parts and improve service life; shot peening is used to remove or It is not required to keep accurate size and outline of medium and large metal products and scale, rust, molding sand and old paint film on forgings and castings; shot peening is mainly used here to remove oil and rust on steel rod 3.

Fill the cavity 2 with the molten metal that needs to be poured, and the steel rod 3 exchanges heat with the molten metal, causing the temperature of the liquid metal in the center of the casting to be lower than that of other parts of the casting to solidify first, so that the temperature inside the casting gradually rises from the inside to the outside High, which is beneficial to the feeding of castings, and dense castings can be obtained; before the castings solidify, a certain metallurgical reaction occurs between the high-temperature molten metal and the surface of the steel rod 3, so that the surface of the steel rod 3 melts, and when solidified, the steel rod 3 and the casting are combined together; if the diameter of the steel rod 3 is large and the pouring temperature is low, the metallurgical reaction between the molten metal and the surface of the steel rod 3 cannot occur, and when solidified, the steel rod 3 and the casting cannot be combined to form a non-fused interface.

Specifically, when the thickness of the casting is 40mm and the pouring temperature is 1500°C, the steel bar 3 is 20# steel, and the molten metal is gray cast iron HT250.

The inspection process of the fusion of steel rod 3 and the casting, after pouring is completed and the casting is cooled, the casting is cleaned, then cut from the middle of the test block, and observed after metallographic polishing; after many experiments, the metallurgical fusion of steel rod 3 and the casting can be obtained The relationship between the pouring temperature and the diameter of the steel rod; in addition, changing the size of the casting and performing the same experiment can also obtain the relationship between the pouring temperature and the diameter of the steel rod 3 when the steel rod 3 is metallurgically fused with the casting under different thicknesses of the casting.

Compared with the prior art, the castings cast from the mold for testing the melting degree of the inner cooling iron can help to quickly and accurately test the relationship between the modulus of the inner cooling iron, the pouring temperature and the modulus of the casting, and then obtain the The design method can more reasonably design and cast the internal cooling iron suitable for thick and large iron castings.

Inspired by the above ideal embodiment according to the utility model, through the above description content, relevant staff can completely make various changes and modifications within the scope of not deviating from the technical idea of the utility model. The technical scope of this utility model is not limited to the content in the description, but must be determined according to the scope of the claims.

Claims (3)

1. A mold for testing the degree of melting of internal cooling iron, characterized in that it includes a main body (1), the main body (1) is rectangular, and a rectangular cavity (2) is provided inside the main body (1), The bottom of the cavity (2) communicates with the outside through a pouring channel (4) arranged on one side of the cavity (2), the lower end of the pouring channel (4) communicates with the cavity (2), and the pouring channel (4) The upper end of the cavity (2) is provided with a bell mouth, and the inside of the cavity (2) is provided with a number of vertically parallel steel rods (3), and each steel rod (3) is located at the center of the bottom surface of the cavity (2) along the length of the rectangle. In the vertical plane where the line is located, the distance between two adjacent steel rods (3) is equal. 2. The mold for testing the melting degree of internal cooling iron according to claim 1, characterized in that, the length of the main body (1) is 400mm, the width is 40mm, and the height is 300mm, and the steel rod (3) There are 5 steel rods (3) with diameters of 5mm, 8mm, 10mm, 12mm and 15mm respectively, and the distance between two adjacent steel rods (3) is 50mm. 3. The mold for testing the melting degree of the internal cooling iron according to claim 1, characterized in that, the steel bar (3) is made of low carbon steel, medium carbon steel, high carbon steel or stainless steel.