Sample decomposition method selection, decomposition method According to data, SiC is stable, insoluble in hydrofluoric acid, sulfuric acid and other acids, but soluble in molten alkali. In this paper, Na2O+KOH and KNO3+KOH are used to melt the gas lamp, respectively. After leaching with hot water and acidification with hydrochloric acid and nitric acid, the insoluble residue is visible to the naked eye, indicating that the above solvent cannot be used to decompose silicon carbide. Therefore, it cannot be measured by the potassium fluorosilicate volumetric method. According to the decomposition ability of the mixed solvent, the mixed solvent is selected for high temperature melting. Decomposition temperature and time According to the nature of SiC, 1050e and 1100e were selected to decompose the sample, and the results were consistent. This article uses 1050e. During the decomposition of the sample, take out the observation every 10min, two-dimensional motion mixer found that after 30min, the sample becomes clear, complete decomposition. This article chooses 30min. Leaching acidity Due to the ease of polymerization of silicic acid, the sample leaching acidity should be less than 2mol/L. In this paper, the leaching acidity of the SiO2 determination method in ore is adopted, that is, leaching with (1+6)100 mL of hydrochloric acid.
The acidity of the chromogenic acidity silicon molybdenum heteropoly acid is generally controlled at C(H+)=0.10.6 mol/L. According to the daily analysis of SiO2 in refractories, this article uses a reagent blank solution to regulate and control the color development acidity. Elimination of Interfering Elements In addition to SiC, the remaining components of silicon carbide-containing refractory products are mainly SiO2, Al2O3, CaO, MgO, Fe2O3, TiO2, MnO, Cr2O3, P2O5, and free carbon. SiO2 can be removed by volatilization with hydrofluoric acid; free carbon can be burned and removed in a high-temperature furnace, and non-ferrous metals such as Cr2O3 can be eliminated through preparation of a reference. P2O5, Fe2O3, etc. due to the coordination of oxalic acid can eliminate its interference. However, this method is not suitable if it is a phosphate binder refractories. The rest of the ingredients did not interfere. The reliability of the results and the scope of application Because there is no standard sample, pure silicon carbide results can only reflect the recovery rate, the synthesis of the sample is difficult and can not be exactly the same as the actual sample. In this paper, we used the gravimetric analysis method that does not require the standard sample, and decomposed the sample by the experimental method described in this paper. The result of dehydration using the perchloric acid dehydration method was compared with the measurement results of the method described herein. The method is applicable to the determination of SiC in SiC materials and has a wide range of applications. SiC in a refractory product containing 1% or more of SiC can be analyzed. This method measures 30% or more of SiC, and the allowable difference can be controlled below 0.3%. For SiC with content greater than 30%, if the differential photometric method is adopted, the sample weight and the fractionation rate are not reduced, and the allowable difference can be controlled below 0.5%. . The method is easy to operate and has less interference. The sample solution prepared by the method can be used for measuring Al2O3, CaO, MgO, Fe2O3, and the like.
The development and development of Bulldozer Spare Parts and Loader Spare Parts types must meet the work adaptability of different working conditions, and must maintain the maximum component versatility (or interchangeability) with the basic model, which will bring extremes to the users. Great convenience. In order to facilitate the purchase of accessories, the manufacturer has retained the parts number of Komatsu Corporation of Japan, and only the parts designed by the company in the modification have been numbered by their own manufacturers.
The Crawler Bulldozer and Crawler Excavator is mainly composed of an engine, a transmission system, a working device, an electric part, a cab and a hood. Among them, mechanical and hydraulic transmission systems include hydraulic torque converters, coupling assemblies, planetary gear-type power shift transmissions, central transmissions, steering clutches and steering brakes, final drives and travel systems.
The power output mechanism drives the working pump, the variable speed torque hydraulic system variable speed pump and the steering brake hydraulic system steering pump in the hydraulic system of the working device by means of gear transmission and spline connection; the sprocket represents the final transmission mechanism of the secondary spur gear transmission (including left and right final drive assemblies); track shoes including track assemblies, trolley frames and suspension assembly systems.
Heavy Construction Machinery Bulldozer, Crawler Bulldozer, Shantui Bulldozer, Bulldozer with Three-Shank Ripper
Jining Changsong Construction Machinery Co., Ltd. , http://www.jncsmachinery.com