38results about How to "Same expansion coefficient" patented technology

The invention relates to a dual-band multi-polarization common-aperture waveguide slot antenna. Including L-band vertically polarized antennas, C-band vertically polarized antennas and C-band horizontally polarized antennas with equal lengths; and all of them are waveguide slot antennas; C-band vertically polarized antennas and C-band horizontally polarized antennas form a C-band dipole The polarized antenna array is located at the upper part, and the L-band vertically polarized antenna is located at the lower part; the L-band vertically polarized antenna, the C-band vertically polarized antenna and the C-band horizontally polarized antenna are all fed through the center of the antenna waveguide through a coaxial connector. Electrically, the coaxial connector and the waveguide form a 3dB power divider; realize the excitation of the L-band vertically polarized antenna, the C-band vertically polarized antenna and the C-band horizontally polarized antenna. The invention realizes sharing of multiple waveguide slot antennas on the same physical aperture area. Compared with the dual-band multi-polarization microstrip common-aperture antenna, the antenna has high efficiency, high polarization isolation, low cross polarization, and low power capacity. Great advantages.

The invention discloses a connection structure between glass and Kovar, which comprises a high boron glass tube of a solar heat collecting tube and a Kovar alloy tube, the Kovar alloy tube is inserted into the high boron glass tube of a solar heat collecting tube, and the outer side of the Kovar alloy tube is A micron kovar solder paste layer is provided at the joint, and a copper-plated layer is provided on the inner side of the high boron glass tube of the solar heat collector tube, and the micron kovar solder paste layer is connected to the copper-plated layer; the micron kovar solder paste layer It includes Fe-Co-Ni alloy particles, binder and 90-95% alcohol. The mass fraction of each component of the micron kovar solder paste layer is: 60-70 wt% of Fe-Co-Ni alloy particles, 20-30 wt% of binder, 5-10 wt% of 90-95% alcohol. The above-mentioned technical solution of the present invention has the following beneficial effects: the inventive method of using low-temperature sintering uses micron Kovar solder paste as an intermediate material to realize glass-Kovar sealing, which is reliable at high temperature, has no residual stress, and has good mechanical properties.

The invention relates to an efficient silicon carbide corundum rare earth ceramic composite grinding wheel which comprises the following raw materials in percentage by weight: 30-75wt percent of silicon carbide abrasive, 25-70wt percent of corundum abrasive, 12-22wt percent of rare earth ceramic and 3.5-8wt percent of normal-temperature binding agent. The composite grinding wheel is manufactured by the steps of calcining, ball-milling, blending, moulding, drying, sintering, and the like. The grinding wheel of the invention has the advantages of high grinding force for grinding a difficult grinding material, sharp grains, high self sharpening, shedding in time of blunt grinding grains and no burning on workpieces. Compared with the traditional single grinding material common ceramic binding agent grinding wheel, the efficient silicon carbide corundum rare earth ceramic composite grinding wheel obviously improves the grinding efficiency; and compared with a grinding wheel adopting an expensive superhard grinding material (artificial diamond or CBN (Cubic Boron Nitride)), the efficient silicon carbide corundum rare earth ceramic composite grinding wheel obviously reduces the grindingcost and has wider adaptation and favorable economic and social benefits.

The invention discloses a copper-nickel-silver brazing paste and a preparation method thereof. The invention adopts copper-nickel-silver with more stable alloy properties as the main base material, and prepares a copper-nickel-silver brazing paste through the cooperation of brazing flux. Soldering paste, which can meet the needs of brazing heat dissipation materials and external parts based on copper, silver, nickel and other base materials. The copper-nickel-silver brazing paste obtained in the present invention has high brazing joint strength after welding , The thermal conductivity and expansion coefficient are consistent with the heat dissipation substrate, which can effectively avoid poor product performance caused by differences in expansion coefficient.

The invention discloses a combined air supply nozzle, a rotary kiln and a preparation method thereof, which are mainly designed to improve the defects of the existing air supply nozzle such as short service life and inconvenient installation and replacement. The combined air supply nozzle of the present invention is composed of a nozzle cover and a nozzle core; wherein, the nozzle cover is a tubular structure, and the inner cavity of the tubular structure is adapted to the outer dimension of the nozzle core; the nozzle core is placed At least one through hole penetrating through the two ends of the nozzle core is provided in the nozzle sleeve and in its core. The nozzle core and nozzle cover of the present invention are pre-extruded and then fired at high temperature, which are relatively easy to install and replace, and their strength and practical performance are not limited by the kiln curve. In addition, outside air is ejected through multiple through holes in the nozzle core, which not only can better mix the air with the combustible gas in the kiln, but also can evenly burn the kiln temperature and reduce the temperature difference between the flame and the material.

The invention relates to the technical field of ceramics, in particular relates to Ru porcelain clay and a preparation method thereof, and also relates to Ru porcelain calcined with the Ru porcelain clay and a preparation method thereof. The Ru porcelain clay consists of 23 to 33 parts of Fengxue soil, 17 to 27 parts of Banpo soil, 10 to 25 parts of Tanggou soil, 8 to 20 parts of black soil, 5 to15 parts of quartz, 1 to 8 parts of sandstone, 0.5 to 2 parts of feldspar and 0.5 to 2 parts of alkaline ore. The Ru porcelain calcined with the Ru porcelain clay has excellent quality, compact porcelain body, high hardness and strong surface appearance, and when the Ru porcelain used as tableware and tea ware, remaining tea stains and oil stains are easy to clean, and practicability is enhanced.

The invention provides an arrangement structure for the lower header of the boiler cladding wall, which can eliminate the welding stress and expansion stress between the sealing steel plate and the pipe, solve the problem that the sealing steel plate tears the pipe wall due to the change of stress, and ensure Ensure the normal use of the boiler wall tube, and then ensure the normal use of the boiler. It includes the lower header of the front wall, the lower header of the side wall, the elbow of the side wall, and the sealing steel plate. The sealing steel plate is welded to the lower header of the front wall, the lower header of the side wall, and the elbow of the side wall. The isolation structure is characterized in that: the lower header of the front wall is located above the level of the lower header of the side wall, the bend of the side wall is one, and the horizontal distance of the bend of the side wall is reduced to the original Half of the sealed steel plate is specifically a carbon steel sealed steel plate.

The invention relates to a preparation method of a homogenic inorganic membrane tube, belongs to the technical field of inorganic membranes and relates to a preparation method of inorganic membrane tubes and membrane tubes thereof. The method comprises the following steps of: 1) screening homogenic base materials with uniform or same particles in size; 2) uniformly mixing base materials with water and water glass to form an inorganic membrane tube raw material; 3) filling the inorganic membrane tube raw material to a centrifugal casting inorganic membrane tube machine and manufacturing a membrane forming tube by centrifugal force; and 4) demoulding, sintering and cooling to form. The homogenic inorganic membrane tube provided by the invention is simple to manufacture and free from drying and demoulding, so that the production efficiency is greatly improved and the production cost is lowered. The inorganic membrane tube products prepared by the invention are consistent in filter layers, and the filter precision of the tube products washed and damaged is still maintained consistent.

The invention provides an internally-arranged cremator heat exchanger. The internally-arranged cremator heat exchanger comprises an air inflow pipe, heat exchange units, inner spray pipes and hot air spray pipes. The internally-arranged cremator heat exchanger is technically characterized in that the air inflow pipe is connected with a preheating pipe, the preheating pipe is arranged on the upper side of a vault of a hearth, the heat exchange units communicated with the preheating pipe through the inner spray pipes are arranged in the portions, on the two sides of the hearth, of a furnace body, the heat exchange units are hollow refractory prefabricated parts, the hot air spray pipes communicated with the hearth are arranged on the upper portions of the heat exchange units, and air outlets of the hot air spray pipes correspond to the middle of a bogie. The heat exchange units are the hollow refractory prefabricated parts, are directly laid inside the furnace body, and make direct contact with flames in the furnace body, and therefore the heat exchange temperature is high. Compared with a metal heat exchanger, the internally-arranged cremator heat exchanger is long in service life and free of oxidation corrosion, the expansion coefficient is consistent with that of the furnace body, and no damage is caused to the furnace body. Preheated air is further heated through the heat exchange units, the hot air temperature is higher, the incineration effect in the hearth is further improved, and fuel is effectively saved.