Bone China 10 semi-finished product defects

( 2) Grouting bone China model 1) New mould grouting, first clean up the bone porcelain model of working face, and gently wipe the outermost layer of skin, paint and dust. In the drying room drying temperature wants even, moisture content is usually 6 - High control in 16-15% 18% dry brush water, edges and corners are too pointed with fine emery cloth, polishing, using multiple pieces of bone China model, pay attention to the concave and convex line seam, otherwise go pulp and cause cracking. 2) Pouring large varieties of bone China model, taking a bone porcelain body have different thickness, appearance, uneven and bending complex before grouting with fine silk or cloth brush attached to the bone China internal model ( Bone China body easy to crack) Reduce the bibulous rate of bone China model, increase the bone porcelain body tension. Can brush talcum powder, reduce bone porcelain body in the drying process in mobile friction due to contraction. ( 3) Bone China grouting operation 1) Using bone China mud must strengthen its liquidity stirring often, according to the thickness of bone porcelain body master living mud in the bone China time duration of the mould, yu slurry dumping is clean, prevent the bottom of the thick, cause bone porcelain body contraction. 2) Grouting bone porcelain products of adhesive ( Tsui, put, ears, feet, etc. ) Attachment of seam allowance, to cutting flat, or stab into the pits after the dry humidity of adhesive all accessories should agree, radian kiss, bonding density, cannot brush water too much big bone porcelain varieties of splice, stick it sticker or at a thin cloth, also can prevent the cracking. ( 4) Bone China mold release, according to the thickness of bone porcelain body, Shi Yin mold condition, appropriate control demoulding time can't release too early and too late. Indoor temperature should be kept in the 18 - grouting workshop C, bone China mud temperature 15-24 Temperature of 20-20 ℃, bone China model 30 ℃, take appropriate drying temperature in the 50 - Between 60 ℃. Dry too anxious, want to heat evenly to the bone China body storage, brackets, plate, shape to adjustment, cushion layer of tissue paper on the plate. Such as big bone porcelain varieties, the pressure produced by its own gravity affect shrinkage, must be a layer of billet on the plate mat, powder or quartz powder, in case of uneven shrinkage and cracking. ( 5) Roasting, should according to bone porcelain body in the process of heating the characteristics of linear curves, formulate correct firing system. Wall thickness of the big bone China products, more to strictly control the heating rate and cooling rate, must not act too hastily. ( 6) Bone China products shape design is reasonable. 2, bone China heavy shoulder, brain meaning: also known as bridge shoulder brain and thick slab deformation. Grouting forming bone porcelain body, shoulder sinking or skewed deformation occurred after drying, classified as deformation, produced in the design, such as ingredients, grouting and firing process. The reason: 1) Bone China poorly designed or bone China gypsum model structure is not reasonable cause grouting body mud, improper storage, lead to cantilever part of easy deformation and subsidence. ( 2) Bone China mud mixed uneven, drying shrinkage is differ, or mud particles interloper, too much alkali ( Incorrect or electrolyte) Viscosity, drying shrinkage, improper proportion of moisture content on the high side. Grouting die too meddle too wet or dry wet not divide evenly, bibulous rate is inconsistent form bone porcelain blank thickness even, uneven shrinkage deformation. ( 3) Bone China body mold release early and forced demoulding, stored in the uneven plate, due to wet billet didn't put a right to make its drying shrinkage and deformation, the bone porcelain blank refinement when hot water too much and not uniform, can also cause heavy shoulder brain deformation. ( 4) Local kiln temperature is too high. - - - - - - - - - - - - - - - - - - Bone China big capacity of the cup