Cracks refer to the grain-like defects formed by the cracking of the product body and glaze. Once the body of the bone china advertising cup is disturbed by external force, it will crack.
Click on the location of the crack below. The main causes of various cracks are described in detail.
1. Bone China Advertisement Cup Bone china spallation. Spallation refers to the phenomenon that the carcass is delaminated and cracked. The middle layer of the body formed by grouting is also called heavy skin.
①The billet itself contains air and there is an interlayer;
② Improper forming operation.
2. Bone china advertising cup opening crack refers to the cracking of the mouth of the product.
① The plasticity and bonding of the mud mud are poor; the moisture content is too low or uneven;
② During hot rolling forming, the temperature of the rolling head is too high; during spinning and rolling forming, the cutting edge is not smooth and clean, and there is residual mud attached to the edge of the green body, which makes the edge of the green body dry and shrink unevenly;
③ During grouting, the performance of the mud is poor; the plaster mold is too dry or its edge absorbs water too fast;
④ The demoulding is too dry or too late, and the double mold operation is improper, so that the edge of the green body is damaged;
⑤ When trimming, glazing, underglaze decoration, and taking glaze, the edge of the blank body is too thin, not dry, not placed stably, improper operation, excessive force and damage to the blank or damage. When loading the blank, take the blank with one hand, and break the blank with the thumb;
⑥ Mechanical equipment is not sophisticated. Great vibration.
3. Bottom cracking of bone china advertising cup Bottom cracking refers to the cracking of the bottom of the product.
①During spinning and rolling forming, the mud material is too hard or the moisture is uneven; the material is added after the feeding is not enough; the mud feeding is not correct; the pressing action is too violent;
② During the processing of semi-finished products, the billet is too wet, the area of the billet sucker used is too small, and the force is too large when sucking and releasing the billet;
③ When digging the bottom, the mechanical equipment vibrates, and the force on the green body is unbalanced, causing cracks on the inner surface of the green body, or the cracks are in the shape of long inner surface and short outer surface, and the green body is sunken inward.
4. Bone china advertising cup shoulder crack Shoulder crack refers to the cracking of the shoulder of the product.
① The plasticity and bonding of the billet are poor, so that the dry strength of the billet is low; the moisture content of the billet mud is too low; the position of the mud throwing is not correct when forming;
②During the processing of semi-finished products, when the blank is placed on the blank seat, the shoulder of the blank body is damaged; the diameter of the blank seat is too large, too small or its shape is not suitable for the blank;
③ When sucking the billet with the billet suction device, the pressing force is too strong or the billet is not sucked stably, and the billet falls accidentally and damages its shoulder.
5. Cracks in the bottom of the bone china advertising cup Cracks in the bottom of the foot of the product refer to the cracking of the bottom of the product.
① The moisture content of the mud is too low, and the plasticity and bonding are poor; when forming, the diameter of the mud cake is too small, the position of the mud is not correct, and the forming pressure is too large;
②The drying time of the belt mold is too long, the demoulding is too late, and the bottom foot of the green body cracks in the model; when the mold is demoulded, the foot is damaged by the residual mud in the model vent hole, causing the bottom foot to break;
③ Improper operation of digging the bottom and taking glaze; the cutting tool is not sharp;
④ When grinding the gray cloth, the technique is improper, and the fingers are too hard on the bottom of the blank to damage the green body, and the cracks generally extend from the bottom foot to the shoulder;
⑤Large products have too little powder on the bottom, which will affect the shrinkage of the green body during firing, making the sintering and shrinkage of the green body uneven.
6. Cracks in the mouth and ears of a bone china advertising cup refer to the cracks at the joints between the mouth, ears, accessories and the main body.
①The body of the main part in the bonding part is too thin or too wet; the moisture content of the mouth, ears, and accessories is too different from the main body, or the shape of the joint does not match; or the bisque firing temperature of the accessories and the main body is different , the water absorption rate is different.
② The bonding mud formula is improper, and the viscosity is poor; the bonding mud is not prepared well, and the moisture is too low.
③ Unskilled bonding technology, too much force or too light when bonding, so that the bonding mud around the joints of the mouth, ears, and handles is unevenly sprayed or sprayed out without pressure, resulting in poor bonding; bonding the spout , When applying mud, etc., too much force will damage the bonding parts; during the bonding operation, the body is not taken and placed correctly, which will cause the body to be impacted.
7. Eye cracks in bone china advertising cups Eye cracks refer to cracks formed around the leaking holes of pot products, or cracks on the edge of Linglong eyes.
① The clay has poor plasticity and bonding, and the dry strength of the green body is low.
②Drilling holes when the moisture content of the green body is too low; the drilling machine itself has faults, the drilling tube does not meet the requirements, the drilling equipment is not sharp, and the force is too large when drilling.
Post time: Dec-06-2022