NGK ADREC Co.

Kani, Japan

NGK ADREC Co.

Kani, Japan
SEARCH FILTERS
Time filter
Source Type

Patent
Ngk Insulators and NGK Adrec Co. | Date: 2017-04-19

A shelf (10) for thermal processing inludes a board (30) having a flat plate shape, a column (20) having a support part (24) which supports the board (30) from below, and an opposing part (22) which is located above the support part (24) and opposing an upper surface (30a) of the board (30), and a projection portion (40) projecting from one of the upper surface (30a) and a lower surface (30b) of the board (30) disposed between the support part (24) and the opposing part (22), wherein the projection portion (40) is restricted to move along the flat plate shape of the board (30). One of the support part (24) and the opposing part (22) that is located on a side of the one of the upper surface (30a) and the lower surface (30b) opposes a side surface of the projection portion (40), and makes contact with the projection portion (40) to restrict the board (30) from moving relative to the column (20) along the flat plate shape of the board (30).


Nagasaka M.,Gifu University | Yoshida M.,Gifu University | Sakurada O.,Gifu University | Tanaka M.,Japan Fine Ceramics Center | And 2 more authors.
Zairyo to Kankyo/ Corrosion Engineering | Year: 2015

Rigid Media Tube Filters (RMF) bonded to coarse-grained alumina by aluminum borate reaction bond layer (9Al2O3·2B2O3; 9A2B) are used to remove solid impurities from the molten aluminum. Molten aluminum corrodes the 9A2B bond layer. To improve corrosion resistance of the RMF, we examined yttrium titanate (Y2Ti2O7; YT) coating using YT aqueous precur sorsolution. As results of the corrosion resistance evaluation of the filters in the molten aluminum, 9A2B bond layer of the coarse alumina was corroded about 2 weeks, but that 5 coats of YT remained for over 4 weeks.


Yamakawa O.,NGK ADREC Co. | Shirakawa H.,Ngk Insulators | Hashiba M.,Gifu University | Sakurada O.,Gifu University
Ceramics International | Year: 2010

We performed a study of a tube filter binding agent for molten aluminum (rigid media tube filter, RMF). In this study, we examined the formation mechanism of aluminum borate (9Al2O3·2B2O3; 9A2B) from Al2O3-B2O3-MgO frit composition, which used MgO instead of CaO in the Al2O3-B2O3-CaO frit in our previous report. The results indicated that crystallization of 9A2B is easier in Al2O3-B2O3-MgO compared to Al2O3-B2O3-CaO, in that crystals are formed with only a heating process, and the amount of crystallization increases depending on the calcination temperature and the heat load over the retention time. A tube filter made of Al2O3-B2O3-MgO frit contained a larger amount of 9A2B crystals and therefore its strength did not deteriorate until a very high temperature of 1200 °C was reached, and its coefficient of thermal expansion was low. This is an advantageous property for RMF used under constraints and high temperatures. In addition, when the amount of 9A2B crystal formation increases, the wettability of molten aluminum decreases, and it becomes more difficult for molten aluminum to impregnate the filter material, but we found that corrosion resistance was high. © 2009 Elsevier Ltd and Techna Group S.r.l.


Yamakawa O.,NGK ADREC CO. | Shirakawa H.,Ngk Insulators | Hashiba M.,Gifu University | Sakurada O.,Gifu University
Keikinzoku/Journal of Japan Institute of Light Metals | Year: 2010

The quality of molten aluminum is dependent on the methods used for its treatment, and the rigid media tube filt (RMF) is the most reliable means of removing inclusions from molten aluminum. In the present study, we examined the effects of adding SiO2 to alumina filters bound by aluminum borate (9Al2O3·2B2O3:9A2B) to improve the penetration of molten aluminum into the filter. With the addition of SiO2, although the amount of 9A2B crystal was decreased by form tion of borosilicate glass and 9A2B crystal shape became short and small, the penetration ratio for adding 10 mass% SiO2 was substantially improved and the amount of Si outflow and corrosion resistance were reduced. The degrees of thermal expansion of alumina filters with 10mass% SiO2 were similar to those of non-SiO2-bound filters. In conclusio alumina filters with bound 9A2B crystals including 10mass% SiO2 showed improved penetration of molten aluminu and reduced both Si outflow and corrosion resistance. As the thermal expansion of the filter was similar to that of filters containing no SiO2, this material is suitable for bonding of RMF heated to 800°C under restriction.


Yamakawa O.,NGK ADREC Co. | Shirakawa H.,Ngk Insulators | Sakurada O.,Gifu University | Hashiba M.,Gifu University
Keikinzoku/Journal of Japan Institute of Light Metals | Year: 2010

Rigid Media Tube Filter (RMF) is the most reliable treatment method to remove impurities from molten aluminum. The lifetime of RMF depends upon the amount of impurities normally filtered, but sometimes the molten aluminum insufficiently penetrates the RMF. The result of analyzing a half used cartridge insufficient positioning, namely, the centre and upper section of the cartridge show the lowest penetration ratio. We simulated a flow vector and velocity in a filter box by the Finite Element Method (FEM). The result of FEM shows that flow vector in the center of the filter box has the same result, slow velocity near the inside tubes, regardless of a inlet position. And also, the flow velocity at the tube's center is slower than that at both the inlet and outlet. The FEM result is similar to the actual result of the penetration ratio. It is assumed that low aluminum head pressure causes alower penetration ratio in the upper section. In conclusion, we get similar result from FEM analysis and actual penetration ratio, however, penetration ratio is influenced by operational conditions and not merely flow in the filter box.


Patent
Ngk Insulators and NGK Adrec Co. | Date: 2015-03-25

A setter for a roller hearth kiln of the present invention is made up of a substantially quadrate planar body (1), and a protrusion (2) formed at the edges of the planar body (1). Four sides defining an outline of the planar body (1) each have a central straight part (3) and tapered parts (4) at both ends of the straight part, the tapered parts being tapered inwards toward respective corners (5), so as to prevent damage to setters when adjacent setters contact each other. The protrusion (2) may be formed all around the circumference, or along two opposite sides.


Yamakawa O.,NGK Adrec Co. | Shirakawa H.,Ngk Insulators | Sakurada O.,Gifu University | Hashiba M.,Gifu University
Keikinzoku/Journal of Japan Institute of Light Metals | Year: 2010

The quality of molten aluminum is dependent on the methods used for its treatment to remove impurities. Of these, rigid media tube filter (RMF) has been the most reliable. RMF bound coarse grain of alumina by 9Al2O 3·2B2O3 has been used widely all over the world. The purpose of this study was to examine the filtration efficiency of RMF using an aqueous suspension of ceramic powder instead of molten aluminum. During actual operation, inclusions accumulate on the surface of RMF to form a cake layer. But the cake formation was not expected in aqueous suspension, since its filtration efficiency showed initial operational conditions, i.e. surface and internal filtration. The results of our experiment clearly showed that filtration efficiency of RMF depended upon pore size and the operation condition. Namely, the filtration efficiency of small pore RMF allowed as high as possible removal of fine inclusions. It was confirmed that maximum inclusion size that could possible be filtered, was approximately 10% of maximum RMF pore size. Also, the operation conditions for higher filtration efficiency, was a slower flow rate and an aqueous suspension of low inclusion concentration. The filtration performance for double layers RMF was influenced by a smaller pore size and the filtration resistance reduced as compared to single layer. As the result of aqueous suspension was similar to that of TiB2 added molten aluminum, it was assumed that the aqueous suspension examination method was reliable.

Loading NGK ADREC Co. collaborators
Loading NGK ADREC Co. collaborators