石蜡铸造工艺Paraffin casting process.docx

1、石蜡铸造工艺Paraffin casting process石蜡铸造工艺（Paraffin casting process）The lost wax casting process was developed from ancient casting process. More than 5000 years ago in the late Neolithic period, the ancient Chinese craftsmen in the manufacture of bronze, widely used lost wax casting process. At the time

2、of the craftsmen according to the characteristics of plasticity and heat volatile beeswax, beeswax first carved wax to shape, and then wrapped in wax and clay and set aside a small hole, dry after roasting, the wax and clay gasification volatilization, has become a ceramic shell, the inner wall of t

3、he shell left female mold wax. At this time, the molten metal is injected into the shell along a small hole, and then the shell is broken after cooling to obtain the required metal blank. The basic principle is as modern lost wax casting technology, but more sophisticated. This is mainly reflected i

4、n the more stringent requirements of accurate wax type. Get the wax in modern technology not only directly carved on wax, but also through the metal mold (original version) silicone molding die is obtained, and then the wax wax injection after silica gel die. Casting material is no longer clay, inst

5、ead of casting gypsum. Such products are much finer than those of ancient ones.Lost wax casting process are: plastic mold - plastic mold pressing - wax injection (mold) - dressing wax (welding wax), ash (weighing) - filling - vacuum - tube gypsum gypsum plaster, gypsum, natural solidification baking

6、 and casting molten gold - fried plaster and flushing, pickling, cleaning (weighing) - Blank (shearing rolling light). Each process is described below.I. pressing glue mouldThe adhesive used for making rubber mould is rubber sheet with adhesive on both sides. General use of imported film, Castaldo c

7、ard for more. One of the price is relatively low, because fewer ingredients contained in natural rubber, vulcanized hardness is slightly larger, but the die time is short, suitable for operation in experienced mold division; another slightly higher prices, with natural rubber more fully, soft textur

8、e, full of toughness, suitable for more complex, in the pattern shape small size and obvious concave silver version of die, not easy to break in when remove the wax wax.The storage of raw films should be kept under the control of the storage temperature of 20 degrees Celsius. Generally, they can be

9、stored for one year and stored at 05 degrees Celsius for 23 years.In addition, the utility model also has a rubber mold which is made into a series of sizes and thicknesses in advance, and the inner wall is provided with convex and concave connecting feet, and the utility model is convenient to use.

10、The apparatus for pressing dies is a (vulcanizing) press molding machine, and its main components consist of two heating plates with internal live wire and temperature sensitive device, a thermostat, and a timer (some models do not have such a device). Die machine is also equipped with lifting screw

11、, used for die and take out.Matched with the press die frame, according to the number of holes, it can be divided into single plate, double plate, four plate and so on. The material for making die frame is usually aluminum alloy. The size of the general die frame is 48mm * 73mm, and sometimes the he

12、avy die frame is used to press the larger original. The size is usually 64mm * 95mm.Glue mould seems simple, in fact, there are many details must pay attention to. Ensure the die frame and the film students must first clean, should as far as possible will die die before the box clean, wash hands and

13、 work station operator; secondly to ensure between the original and not rubber adhesion, to do this, we should give priority to the use of silver, if it should be coated with silver coated after the die, because it is easy to bond with rubber adhesion together; again is to pay attention to according

14、 to the specific circumstances to determine the proper curing temperature and time, which not only accord with a certain function, but also the complexity and rubber mold thickness, length and width, the original, usually will die the temperature is 150 degrees Celsius, if the rubber mold thickness

15、in the 3 layer (about 10mm), the general curing time is 2025 minutes, if it is 4 layer (about 13mm), the curing time is 3035 minutes. In turn, the temperature at the same time is also related to the complexity of the original: if the original is complex and small, the vulcanization temperature shoul

16、d be reduced,Prolong the curing time (if some master uses the method of reducing the temperature 10 degrees and prolonging the time twice), on the other hand, if the temperature is too high, it will affect the effect of the die.The quality of the die depends on the quality of the pressed template. I

17、n general, students should first make the film to tightly bonding together, must ensure the film clean first, do not hand in direct contact with the surface of the film, and the film should be born stick and then torn off the protective film on the surface of film students. To ensure that there is n

18、o gap between the rubber and the original. In the landfill rubber should be careful, especially for some small flowers and stone inlay and other fine bottom side pores, must be filled with broken small particles, with sharp objects (such as forceps tip pressure). In order to avoid the rubber mold pr

19、essing too hard, rubber should be buried in landfill in the same direction.In order to ensure the film can be used in a considerable period of time, should make the rubber mold with sufficient thickness, therefore a rubber mold should use at least 3 layers of rubber press. The rubber laminated rubbe

20、r mold should be good after the original overall is slightly larger than the die frame, i.e. width slightly larger (can be forced into a die box), rubber mold thickness in press die box is slightly higher than the plane frame about 2mm.The die must also pay attention to first preheating, add mould p

21、ressing has good rubber box, tighten the handle to make the heating plate pressing die box, curing early can check the heating plate is pressed, the curing time arrived quickly remove the plastic mold, the best natural cooling (of course, also can use cold water showers) that is not hot, you can ser

22、ve hot with a sharp scalpel to open mode of operation of the.Two plastic mold.Plastic mold is a very high technology in jewelry factory, plastic mold because directly affects the quality of the wax and metal blank, but also directly affect the life of rubber mold. Skilled master mold out of the plas

23、tic mold, the wax injection after basically no deformation, fracture, mantle phenomenon, basically do not need to repair welding wax, wax, can save a lot of time dressing, get a higher production efficiency.Plastic mold tool used is relatively simple, and with a scalpel blade, tweezers, scissors, pl

24、iers etc. Note that beginners must use new blades when using the scalpel so that it is not easy to scratch the finger. In the cutting process, to ensure the lubrication between the blade and the film mold, it can be dipped in water or detergent on the blade (but never oil, because the oil will make

25、the mold hard and crisp). Rubber mold four positioning method is usually used, that is to say, out of the plastic mold has four feet of mutual agreement between the fixed legs part by linear cutting, but also the use of cutting curve. The general order of mold opening (take ring rubber mold as an ex

26、ample) is as follows:1) over the rubber mold cooling to a hot air, to flash cut with scissors, with pliers take Xiashuikou block, pull to shell.2) glue the mold nozzle up straight, from the side of the nozzle down the knife, along the four sides of the rubber mold center line cutting, the depth of 3

27、5mm (can be adjusted according to the size of the plastic mold), cut the four sides of the plastic mold.3) cut the first foot from the first lower knife. First, cut two straight edges, the depth is 35mm (can be adjusted according to the size of the glue mould), and then pull the straight edge which

28、has been cut and cut a bevel along the 45 degrees to form a right triangle shape foot. At this time, the cut of the mold should be in two halves of the corresponding Yin, Yang triangle feet match each other.4) according to the previous step of the operation, cut out the remaining three feet.5) opene

29、d the first cut foot, with a blade smoothly along the midline inward cutting (if curve cutting rules should be in accordance with the curve of swing blade, a draw scaly or wavy section), while cutting side pull out rubber mold, be careful when approaching the gate line, with the tip gently open the

30、rubber mold. A nozzle. Then one end of the outer ring along the open ring, ring and insert mouth until.6). This is a plastic mould cutting, difficult and complex steps. If the main stone is inlaid with claws,Cutting heads should be cut along the axis. On the side of two claw ring, the outer end face

31、 to the other side of the cutting head and cutting to the nozzle position, until the. The glue mold has been cut in half, but the silver plate can not be removed.7) rubber die cutting insert, a part. The interval in the main stone on both sides and the side stone mouth, cutting two claw axis along t

32、he main outlet of stone cut, the other two jaws until symmetrical; a residual direction along the main outlet of stone cutting, cutting just intersect with the surface, so that the main stone mouth is zhilizhuang. Then cross in the main roots of the claw stone and stone inlay mouth mouth side knife,

33、 to become the two part. Open cut section, observe whether by glue wire (usually elongated hollow part side stone mouth of the pore and flower formation), if there should be cut off.8) take off the silver plate, and pay attention to observe the adhesion between the silver plate and the glue mold, if any, cut off.9) open the bottom.