The landform types are loess hills covered with sand and sand. The main soil types are cotton sand, hard loess, red clay, aeolian sand, and dam silt. Vegetation types belong to the shrub grassland type. Most of the natural vegetation has been destroyed and artificially remedied. Gradually, the vegetation succession stage, which is dominated by S. bungeana-P. vulgaris, D. dauribreviflora, Artemisia and Artemisia ordosica, has gradually entered. In each sampling point, an earthen borer was used for stratified sampling. The depth of 0 to 10 cm soil layer took a sample every 5 cm, the depth of 10 to 60 cm soil layer took a sample every 10 cm, and the soil was determined by drying method (105e, 10 h). Water content. Agricultural land management is general field crop management; grassland vegetation is ploughing 35 to 36 years from the farmland and basically reduced to S. bungeana. At the same time, portable GPS and compass are used to determine the terrain factors such as slope, aspect and altitude of each sample.
Soil moisture tester After measuring the soil moisture in this area, we can find that diversification of land use patterns on slope land increases the coefficient of variation of soil moisture. Land use structure change is one of the most critical factors leading to soil moisture variation. There is a clear spatial structure for soil moisture in the mixed use of agricultural grasses. Under dry conditions, the average water content in the 0-60cm soil layer maintains a relatively high base station value and range, while the nugget/abutment ratio is relatively low, and they are significantly different with the soil profile distribution, which further explains Different climatic conditions, such as rainfall, can change the variation degree and distribution pattern of soil moisture. In the study of spatial variation of water, different sampling designs should be adopted according to the average water content.
Investment casting technical flow process
The silica sol casting process also called precision investment casting process. It is a less cutting or no cutting casting process. It is an excellent technique in foundry industry. Its application is very extensive. It not only applicable to various types, various kinds of alloy and casting, and produce the casting dimension accuracy and surface quality is higher than other casting method, Even other casting method can not do the complex, high temperature resistant, not easy machining castings, all can be used for investment precision casting process.
The investment casting process, it is a process that use fusible materials make soluble model, and coated with several layers of tailor-made refractory coating on the surface, after drying and hardening become a whole shell, melt the shell model by steam or hot water. Then put the shells in the sand, filling dry sand in all round and modeling. Finally roasting it based on high-temperature in the furnace, the shell after roasting, and getting the casting part after pouring molten metal.
The investment casting process can produce High precision dimensional parts, generally can reach to CT4-6(sand casting is CT10-13, die casting is CT5-7). Due to the complexity of investment casting process, there are many factors influencing the casting dimension accuracy. Such as shrinkage of mold material, deformation of the casting, Shell heating and cooling line quantity change in the process, alloy shrinkage and deformation of castings in the solidification process. The surface finish of investment castings is higher than the ordinary casting, can reach to Ra1.6~3.2.
The greatest advantages of investment casting is casting parts have high dimensional accuracy and surface finish, so it can reduce the mechanical processing. The another advantage of investment casting method is that it can cast all kinds of alloy and complex casting part, special casting high temperature alloy casting part.
The precision of the Steel Casting Part: ±0.15mm~
Smoothness of surface of rough part: Ra6.4;
Shrinkage rate of steel investment casting products: 0.6%;
Material wastage rate: 5%;
General stainless steel casting part machining allowance: 0.7mm;
Surface preparation methods: Sand blasted, Shot blasting, Powder coating, Painting, Plating, Electrophoresis, Polishing.
Our company's production equipment and management system
CNC machining center: 8 sets AIGEMA A-8;
CNC lathe machine: 6 Guangzhou Machines and 7 Shenyang Machines;
Work days of one week: From Monday to Saturday;
Shift work: 2 shift per day;
Working hours: From AM 8:00 to PM 5:00;
2D and 3D drawing Software: AutoCAD, UG, Pro/E, SolidWorks 2013;
QC control: New type NANO CMM, FPI M5000 desktop metal analyzer, Easson projector, Mechanical properties tester.
The steel casting process and machining equipment:
Steel Casting Part
Stainless Steel Lost Wax Casting, Steel Casting Part, Steel Investment Casting Part, Steel Silica Sol Casting Part
NINGBO BEILUN LEMA MACHINERY TECHNOLOGY CO.,LTD , http://www.china-lema.com