Production and Application of Ceramic Plunger for Hydraulic Mud Pump

( Xianyang Ceramic Research Institute 刖 5 hydraulic pressure ceramic plunger mud pump is used for industrial slurry transmission, spray drying tower and filter press has been in existence for many years, because of its stable performance and much favored ceramic enterprises. Continuous in the ceramic industry Because of the long working cycle of the ceramic plugging mud pump, the quality requirements of the alumina ceramic plugs for the wearing parts are quite strict.According to the difference in the outer diameter of the ceramic plungers, the alumina ceramic plungers can be divided into: 085 , 0ll, 0l2, 0l4, 02, 025 and other 6 common specifications, the performance of their products are shown in Table 1. Table 1 performance of aluminum oxide ceramic plunger Water absorption Hardness +: Product phase bending strength (MPA) Bulk density (Kg / M3) Finished surface roughness (Ra) Preparation of corundum 2 blank 2.1 Preparation of billet The calcined a-alumina (low-alkali level 1) of the Zhengzhou Aluminum Plant Cement Plant was used. The fineness was 325 mesh. The chemical composition is shown in Table 2 Table 2 Chemical Composition of Calcined ot-Alumina (Quality) Oxidized Oxide Silica Silica Soda Oxidized Boron Trioxide for Chromium Green in Changsha, with a Percentage of Chromium Oxide >99%. : Al2O3 70%-80% s Quartz 5%-10%, Chromium oxide 2%-3%, clay 10%-13%, water 28%-35%, talc 0.02%, and moderate amount of ceramic additive 3 slurry are prepared by wet ball milling. Formulation, loading into a ball mill, water The parts are controlled at 28% - 35%, material: ball: water = 1:1.5:1, ball milled for 16 hours, sieved with 400 mesh 10,000 holes 2.2 Forming process Molds should be dry plaster molds, molding must be done in the drying room , The use of pressure grouting, plaster mold double-sided pulp, molded plaster mold K intended to see.

The slurry that has been homogenized in the spare pool is pumped into a vacuum tank and pressurized to a pressure of about 4 kgf/cm2 to perform pressure grouting. The grouting speed should not be too fast, and pouring from the grouting port at the bottom of the mold can be performed. Fill the slurry on the grouting port at the time of filling. At this time, stop the grouting, block the grouting port, and continue to manually add mud flash to the grouting beaker (through the bottom) until the mold no longer feeds. The grouting work was basically completed at this time.

2.3 All drying and drying work is carried out in the drying room, which is also the longest process of forming completion. Drying room temperature is controlled at 30-40 °C, after drying the bake for 10 hours, remove the beaker, and use the blanking knife to straighten the mud at the grouting mouth, continue drying at 30-40 days for 16 hours, remove the mold cover, and remove the mold. core. At this time, due to the fact that the moisture content of the blank is still very large, the wet brush can be used to re-build the blank until the blank is intact: after 48 hours, the mold and blank can be buckled down to the pad in the drying room. Above, gently remove the mold and then bake T. At this time, the inner surface and the outer surface of the blank are directly in contact with the hot air within the drying room. The temperature of the drying room is not too high and should be controlled at 3 (: High, the internal and external stress of the billet is not easy to cause the appearance of external cracks and internal striated marks, and the internal flaws of the billets can easily become cracks in the subsequent firing and cause the product to be scrapped.

After another 12 hours, the blank was buckled again on the mat, and the temperature was maintained at 30 T so that the blank was dried uniformly and had a certain strength. Then, move to another drying room, the temperature is controlled to 30T, 24 small, after the time, the whole body is dry and can be fired. At the same time, the next round of the molding process can be restarted.

3Product firing firing Alumina ceramic plunger uses 4 cubic meters of oil-steaming kiln, fan power 18.5 kilowatts, oil pump power 1.5 kilowatts, using Xi'an Instrument Factory's XCT-101 thermocouple thermometer and a 100-axis optical measurement Thermometer temperature measurement 3.1 Installing the kiln in the firing process is critical for the installation of windows. It has a great influence on the product yield. The kiln process uses artificial kiln and the litter uses calcined a-alumina powder from the raw material workshop. First, trim the bottom of the kiln and evenly cover a layer of alumina powder (about 5mm in thickness). Then, put a batch of mud-filled raw material rings (with the same inside diameter and inner diameter of the filled plunger), spread evenly the 5mm alumina powder, and place the green plunger on it gently. This action must be careful and cautious. Uneven loading will cause the raw material gasket to crack. Once it breaks, the raw material gasket and the plug green body will shrink differently during sintering, and the destructive stress will cause the plunger to crack. After placing the green plunger, evenly cover the 5n alumina powder on the upper end and place the cooked gasket. At this time, the kiln operation is basically completed. Then, in order to fill the kiln space. The triangular cone to be prepared will be placed on fireproof mud and placed on the kiln port plunger to block the kiln door, leaving a sample picking hole, and then using a refractory brick to block the sample picking port. Finally, the kiln door will be closed with sealing mud. The end of the kiln process.

3.2 Firing and firing is the most critical step in the production of ceramic plungers.

Because this kind of billet contains a considerable amount of clay, it will shrink when it is fired at high temperature. The temperature rise and fall and the atmosphere in the kiln will be mismanaged, which will inevitably cause cracking of the product and increase the production cost. In the early stage of production, the firing system adopts a constant heating and heating system, which basically maintains the temperature in the kiln at 200-2501 in the first 4 hours, and then evenly increases the temperature at a rate of 45 per hour. The thermocouple is used to measure the temperature of the instrument x-100. When the kiln temperature is 14001, the sluice on the back side of the kiln is put down, and the slag is burned in a reducing atmosphere. When the kiln temperature is 1600, the water absorption rate of the sample is 矣0.1%, the sample is crystallized normally, and the heat is kept for 30 minutes. , Then stop the fire and open some of the kiln doors to cool naturally. When the kiln temperature drops to about 100T, the kiln can be out of production, the yield is about 80%, and the firing cycle is 38 hours.

In order to reduce costs, we have made adjustments and improvements in terms of raw materials and firing systems. Following this, we have achieved a yield of 95% or more, and have significantly shortened the firing cycle, reducing the previous 38 hours to 33 hours. Fuels increase production efficiency.

As the clay in the billet is discharged at 450600, the weight loss rapidly increases. At this time, the clay lattice is destroyed to form metakaolin. Therefore, the heating rate of firing should be slowed down as far as possible before 600 T, and the temperature should be evenly increased. Before metakaolin was reduced to 900, only some of the impurity components were oxidized and decomposed, and the overall stability was relatively stable. Therefore, the heating rate can be appropriately increased. At 1200T:, the upper glassy liquid phase is greatly increased, and the quartz and clay particles are dissolved. Therefore, the heating rate should be slowed down to keep warm.

See the improved firing curve.

Improved firing profile After the previous uniform firing was improved, the product yield was greatly improved, the firing time was reduced from the original 38 hours to 33 hours, and the finished product rate was increased from the original 80% to 95% or more. . Created considerable economic benefits for the company. This firing system has been used up to now, and the product firing quality is stable.

4 Blank Finishing After the firing, the unprocessed blank is called blank. The rough finishing of the blank is performed on the universal external grinder (maximum grinding diameter 320mm, maximum grinding length 750rnm), and the rough grinding and fine grinding are generally performed. Two processes. Finished outer surface finish can reach Ra>.8, plunger length tolerance outer diameter tolerance ±0.01mm, inner diameter tolerance ±0.05mm, full-body plunger without cracks, inspection pass, finished plunger box (built-in shockproof Bubble) packaging people library. (Continued on page 34) Table 10 Addition of mixed standard solution (ml) plus amount of NiO (叩) Measured amount of NiO (call) Recovery: From the test data, the standard recovery of this method is 99.9 102 Between %, the result is reliable.

Based on the above data, determine the amount of reagents as follows: Nickel coloring solution (3.5) Dosage: Select 5ml plus the amount is appropriate; Ammonium persulfate (3.3) Dosage: Select 5ml plus the amount is appropriate; Potassium sodium tartrate (3.4) Dosage: 5m added amount is appropriate; 7, the sample determination step 7.1 Preparation of the analytical solution GKF-type rapid determination of the composition of the silicate component in the instructions for preparation of blank solution, standard reference solution and sample solution.

7.2 Determination Take a blank solution, standard reference solution, and sample solution each 10ml in a 100ml volumetric flask, and then add 5ml of ammonium persulfate 5ml nickel color solution (3.5) and shake. Determined after 15 minutes. The instrument is set to two channels, correction points. The solution can be stabilized lh. 8, the calculation of results: Ce ~ standard percentage of NiO mixed reference solution A sample ~ sample solution of the instrument reading A standard reference solution of the instrument readings A blank solution of the instrument reading (above 21 (Page 5) Application of Ceramic Plungers In the ceramics industry, the use of pneumatic diaphragm pumps and K-90 metal plunger pumps for slurry transmission has been widely adopted for quite some time. With the continuous expansion of ceramic production, the technical requirements have been continuously improved. In 1990s, our country developed and developed an advanced ceramic equipment YB series hydraulic ceramic plunger pump, which is divided into more than 30 models according to the external specifications of ceramic plungers. It is widely used in industrial slurry transmission, equipped with drying towers and Filter presses, etc., have the advantages of high pressure, stability, long conveying distance, low energy consumption, and the like. In addition to its use in the ceramic industry, this product is also widely used in many industries such as chemical industry, coal, papermaking and mining. Due to the excellent wear resistance and corrosion resistance of ceramic plungers, its small size products are also used as electric reciprocating pump pistons, clean water pump pistons, and acid resistant pistons in the pump industry, and have good running performance. The special ceramic pistons that have been burned with special techniques and ingredients will also be used as the driving piston for all types of engines. This will be a direction for the development of China's special ceramics.