Thoughts and Suggestions on the application of vertical parting line in foundry (Qufu Longxiang Smelting and Casting Accessories Co., LTD.)

Because the vertical box-free molding line has the advantages of fast production time, low cost and little influence of human factors, it has been widely used in various foundries. As early as 1969, China introduced the Danish DISA vertical parting molding line. At present, in addition to DISA, there are Spain Lora Mendi Company, Japan Guangyang Company, and China's Baoding Ville casting machine Company and other vertical parting molding lines.

1. Application of vertical box-free molding line

Dongfeng Commercial Vehicle Co., Ltd. under the casting plant one, casting plant two professional cast iron auto parts foundry, is the domestic introduction of DISA vertical modeling line enterprises. At present, there is one DISA 2013 molding line in the first casting plant, and two DISA 2013MK3 lines in the second casting plant.

Among them, the size of DISA vertical molding line sand box in casting plant 1 is 600mm×480mm×250mm, which is mainly used for the production of gray cast iron, ductile cast iron bearing covers, vermicular cast iron exhaust pipes, and ductile cast iron steering bracket for cars, mainly supplying Volkswagen, Cummins Company, and Dongfeng commercial vehicles. The production capacity is affected by the length of the cooling section. The production speed is 100 ~ 150 type /h. The two DISA molding line sand boxes of Foundry 2 are 600mm×480mm×250/350mm, which are mainly used for the production of automobile security castings such as engine main bearing cover, oil seal seat, cushion plate, engine bracket and differential housing. Among them, one line mainly supplies the domestic market and the other line supplies the international market. The weight of the whole box castings is 8 ~ 15kg, the production capacity is 200 ~ 300 types /h, and the annual output of 16,000 tons of castings

2. Characteristic analysis of vertical box-free molding line

Vertical parting boxless injection molding line has the following outstanding advantages:

(1) High precision casting production. Some manufacturers of equipment accuracy can reach ±0.1mm, wrong box quantity ≤±0.25mm.

(2) High production efficiency. For castings with simple structure, the vertical molding line speed of DISA231 can reach 550 type /h, and the production efficiency of ZZ416C vertical parting boxless injection molding machine produced by Baodingville Casting Machinery Co., Ltd. can also reach 500 type /h. Such a high molding speed is an effective guarantee for larger foundries to improve production capacity.

(3) Small sand consumption. Because the sand type is double-sided sand type, the public sand consumption of the two cavities can be reduced. Because it is closed shot sand, there is less scattered sand.

(4) The size of the equipment is small and the occupied area is small.

(5) The degree of automation is very high, and it can basically achieve unattended production.

(6) Due to no box modeling, good air permeability.

(7) Low labor intensity, low noise, less dust.

Similarly, this modeling line also has some problems in the production process:

(1) High core requirements. Because of the vertical direction of the core, the core should be able to ensure reliable positioning of the box, so not only the structure and positioning requirements of the sand core are relatively high, but also the strength and precision of the sand core are higher.

(2) The core will affect the productivity of the machine. Although the production speed of DISA vertical molding line is as high as 510 type /h, the manual combination of core will reduce the production speed of the molding line and become a bottleneck restricting the production capacity of the molding line.

(3) The space under the core is relatively small. Since the sand box is eliminated, the closing and positioning functions of the sand box are integrated into the template on the main platen. Due to the limited travel of the main pressure plate, the core space is small and the core conditions are harsh. In order to solve this problem can be equipped with automatic core mechanism.

(4) The utilization rate of the plate area is low. Due to the vertical molding process, the static and static pressure head of the metal is higher during pouring. Because it is no box molding, in order to ensure that the box is not broken during continuous molding, the sand eating amount around the parting surface is larger than that of the horizontal parting. In order to ensure that there is no "fire running" during pouring, the sand eating amount around the parting surface is larger than that of the horizontal parting, and the pouring riser system and exhaust passage are also distributed on the parting surface, so the utilization coefficient of the parting surface is low.

(5) Special casting process. The casting gate is larger and the process yield is lower than that of horizontal parting casting.

(6) Because there is no sand box, it is easy to expand the box when producing large pieces.

(7) The template is relatively fast. Although the shot sand pressure is not high, due to the shot sand, the template is relatively fast compared to the horizontal parting.

(8) The production of complex parts is difficult. If you want to play the advantages of high production efficiency of the extrusion line, the product is a small part, simple and simple, no core products, if the core machine is used, the depth of the sand core should be considered, and the weight of the sand core is small.

(9) Due to the fast pouring speed, the pouring machine is used to pour. Vertical parting box-less injection molding is generally equipped with plug rod type bottom injection or pressure plug rod type heat preservation pouring furnace, and uses infrared, camera and other electronic technology to control the plug rod action to ensure that it can be continuous pouring and can not overflow.

(10) The production beat is fast, and the cooling speed is accelerated, which has a certain impact on the material uniformity of thick and large castings, and it is necessary to consider whether to breed or extend the cooling section with the flow.

3. Vertical box-free molding line investment advice

In general, the selection of vertical parting molding lines will effectively improve the production speed of the foundry, but this is also based on the "soft and hard" strength of the foundry. In the selection of vertical parting box-free shooting pressure molding line, it is necessary to have excellent hardware, and the hardware facilities such as melting equipment and core equipment should be matched according to the performance parameters of the molding equipment. In addition, the enterprise should have a high level of technical management and sufficient output. It should be emphasized that different modeling lines may be more suitable for different products, and the selection of modeling lines should be considered according to their own products, capital, technical strength, as well as good cost-effective, corporate development needs, etc., and must not blindly follow the trend. For enterprises that need to invest in vertical parting boxless injection molding, the following suggestions are put forward:

(1) The products of the enterprise are mainly large quantities of small pieces, and the type of material is relatively concentrated, and the casting of the sand core combination of no more than 3 can be planned in a vertical parting box-free shooting molding line production.

(2) The melting capacity needs to be matched accordingly to give play to the advantages of high production efficiency of the vertical parting boxless shooting pressure molding line. According to the characteristics of the production of large quantities of small parts, equipped with multiple melting furnaces, a single melting furnace is generally 2 ~ 6t (2t furnace 1h completion, limited melting capacity), according to the vertical parting of the box-free injection pressure molding line production efficiency calculation can be designed multiple melting furnaces, so that it can be convenient to switch different casting production, thereby improving production efficiency.

(3) The vertical parting boxless shooting pressure molding line must also be designed with a long enough cooling section. Because of the vertical parting no box shooting pressure molding line modeling, casting fast, if there is not a long enough cooling section, it can not ensure that the casting is fully cooled before opening the box, resulting in casting material instability.

(4) Vertical molding has high requirements for sand performance, and high-quality sand mixing equipment is needed to match the demand for sand and quality requirements.