14 bone porcelain semi-finished product defects

To overcome the way: ( 1) Bone China clay material is too sticky because gum is too heavy to be appropriate to join solution glue water glass (one by one Sodium silicate Na2i02) , usually with sodium carbonate ( Na2C03 or Na2CO310H20) And at the same time. ( 2) Master control in 3 - grouting with the moisture content of mold 5%, bone China mold too wet grouting, bone China mold used for a trip to a trip to the qing dynasty, circulation and orderly, but because of the chamber temperature is too high to model baked crisp bone also cannot use. New bone China cast at room temperature drying heating drying its temperature to increase again after 36 hours should not exceed 60 ℃. With bone porcelain body keep 40 - drying room temperature 60 ℃, which requires uniform temperature distribution. ( 3) Note before grouting or compact bone China model of oil and dust. Substandard bone porcelain mode shape can't be used. Use time shoulds not be too long, generally single class production team, bone China 20 - modeling using time 10 to 25 days, double class 15 days. 2, bone China dry cracking ( Deformation) Meaning: bone porcelain body in the drying process of the middle cracking deformation, trapped in drying process belongs to crack. The reason: 1) Bone China body structure is complex, uneven thickness, leads to forming ( Machine pressure) Each part of the compression of uneven, dense degree, shrinkage is not consistent, so in modelling design is not reasonable also easy to produce bone porcelain cracking deformation. ( 2) Bone China grey mud composition, viscous material content is less, reduce bone porcelain blank associativity, not shrink resistance of deformation force, material particles thickness difference is too big and uneven, prone to cracking in the dry. ( 3) Bone China grey mud when kneading or forming, the formation of orientational and shrinkage stress caused by not eliminate, cause bone porcelain body parts when the contraction rate, easy to produce bone porcelain deformation and dry. ( 4) Bone porcelain blank moisture content is too high or uneven distribution of water, little parts of the water in the dry shrinkage fast, on the contrary, water slower, more parts of the contraction deformation due to shrinkage and cracking. ( 5) Bone China gypsum mould parts water imbibition is different, especially in the case of using new bone porcelain plaster mold, drying shrinkage and cracking. ( 6) Drying system control is lax, if too fast drying shrinkage, stress is generated in the early dry, bone China body is still in the plastic state, if internal thrown, bone China body will be distorted y; If had hardened surface of the bone porcelain body, internal stress level, makes the bone porcelain body cracking. ( 7) Drying heat source mainly hot air drying, temperature difference is big, irregular bone porcelain body is heated, causing shrinkage range (up and down Tall bone porcelain products even more) : in the dryer, air flow only from one direction, or gypsum mould water quantity is different, the drying rate was uneven contraction caused by the uneven deformation and cracking, early drying, the air flow in the water vapor condensation on the cold grey, dry also can cause cracking. Use natural drying, partial caused by sunlight or local brushed by the wind time drying shrinkage caused by uneven uneven deformation bone China craze. ( 8) Forced demoulding or hands clamp billet, easy injury bone porcelain body. Bone China after demoulding, body place, one side not to carry out the deformation and cracking caused by its own gravity. Bone China body placed in plate, friction resistance between them will hinder the freedom of body contraction, when the friction resistance is greater than the tensile strength of the bone porcelain body itself can produce craze, when this was especially pay attention to in the large objects. Overcome: - - - - - - - - - - - - - Bone China coffee set suits to be continued. 。 。 。 。 。