Abstract: A backflow prevention apparatus is provided with a check valve and a float-type backflow prevention valve, these being installed in this order as one proceeds from upstream to downstream. The check valve comprises a valve seat; a valve member that closes the valve at the valve seat due to an upwardly directed restoring force; and a restoring force exerting member that exerts an upwardly directed restoring force on the valve member. The float-type backflow prevention valve comprises an annular valve seat; a float that rises in accompaniment to a rise in a water level of wastewater to close the valve at the annular valve seat; a guide member that guides movement of the float in a vertical direction; and a constraining member that constrains a lowermost position to which the float can move.

Abstract: A backflow prevention apparatus is provided with a check valve and a float-type backflow prevention valve, these being installed in this order as one proceeds from upstream to downstream. The check valve comprises a valve seat; a valve member that closes the valve at the valve seat due to an upwardly directed restoring force; and a restoring force exerting member that exerts an upwardly directed restoring force on the valve member. The float-type backflow prevention valve comprises an annular valve seat; a float that rises in accompaniment to a rise in a water level of wastewater to close the valve at the annular valve seat; a guide member that guides movement of the float in a vertical direction; and a constraining member that constrains a lowermost position to which the float can move.

Abstract: A powder alloy rolling case (1) includes a side face configuring member (10) formed like a rectangular frame with two members (10a, 10a) combined, and surrounding side faces of metal powder (2); an upper lid configuring member (11) provided to cover one opening of the side face configuring member (10), and covering an upper face of the metal powder; and a lower lid configuring member (12) provided to cover the other opening of the side face configuring member (10), and covering a lower face of the metal powder (2), wherein joints (10b, 10b) between the members (10a, 10a) configuring member (10) are provided in opposing two side faces out of four side faces of the side face configuring member (10).

Abstract: An object of this invention is to provide a case for rolling powder alloy without failures at the time of rolling. The case for rolling powder alloy (1) is formed like a shape of box and comprises a side constituent member (10) forming like a rectangular frame in a combination of two members (10a, 10a) and surrounding a side surface of metal powder, an upper lid constituent member (11) mounting on one opening of the side constituent member (10) and covering an upper surface of the metal powder, and a lower lid constituent member (12) mounting on the other opening of the side constituent member (10) and covering a lower surface of the metal powder. The peripheral edges of the upper lid constituent member (11) and the lower lid constituent member (12) are, respectively, provided with a peripheral wall (11b, 12b) standing upright along an outer peripheral surface of the side constituent member, and the side constituent member (10) is inserted into a space surrounded by the peripheral wall (11b, 12b).

Abstract: A method for producing an aluminum composite material having a great content of a ceramics with ease. The method (a) mixes an aluminum powder and ceramic particles, to prepare a mixed material, (b) subjects the mixed material to electric pressure sintering together with a metal sheet material, to form a clad material including a sintered product covered with the metal sheet material, and (c) subjects the clad material to a plastic working to prepare an aluminum composite material. In the (b) subjecting, the mixed material is sandwiched between a pair of metal sheets or a powder of the mixed material is held in a metal container, the mixed material is placed in a forming die in a state in which the metal sheet material is pressurized by a punch, and the mixed material is compressed together with the metal sheet material. The metal sheet material is made of aluminum or stainless steel.

Abstract: A method of producing an aluminum matrix composite material is described that comprises the steps of: mixing an aluminum powder and a ceramic powder to prepare a mixed powder; providing a lower casing made of aluminum and formed in a hollow rectangular parallelepiped shape having an open top, and a closing member made of aluminum and formed in a shape adapted to hermetically close the open top of the lower casing; packing the mixed powder into the lower casing; closing the open top of the lower casing filled with the mixed powder, by the closing member, to prepare a pre-rolling assembly having the mixed powder hermetically sealed therein; preheating the pre-rolling assembly; and rolling the preheated assembly to obtain the aluminum matrix composite material, where the aluminum matrix composite material includes a pair of metal plates having the mixed powder therebetween.

Abstract: A method of producing an aluminum matrix composite material is described that comprises the steps of: mixing an aluminum powder and a ceramic powder to prepare a mixed powder; providing a lower casing made of aluminum and formed in a hollow rectangular parallelepiped shape having an open top, and a closing member made of aluminum and formed in a shape adapted to hermetically close the open top of the lower casing; packing the mixed powder into the lower casing; closing the open top of the lower casing filled with the mixed powder, by the closing member, to prepare a pre-rolling assembly having the mixed powder hermetically sealed therein; preheating the pre-rolling assembly; and rolling the preheated assembly to obtain the aluminum matrix composite material, where the aluminum matrix composite material includes a pair of metal plates having the mixed powder therebetween.

Abstract: A powder alloy rolling case (1) includes a side face configuring member (10) formed like a rectangular frame with two members (10a, 10a) combined, and surrounding side faces of metal powder (2); an upper lid configuring member (11) provided to cover one opening of the side face configuring member (10), and covering an upper face of the metal powder; and a lower lid configuring member (12) provided to cover the other opening of the side face configuring member (10), and covering a lower face of the metal powder (2), wherein joints (10b, 10b) between the members (10a, 10a) configuring member (10) are provided in opposing two side faces out of four side faces of the side face configuring member (10).

Abstract: An object of this invention is to provide a case for rolling powder alloy without failures at the time of rolling. The case for rolling powder alloy (1) is formed like a shape of box and comprises a side constituent member (10) forming like a rectangular frame in a combination of two members (10a, 10a) and surrounding a side surface of metal powder, an upper lid constituent member (11) mounting on one opening of the side constituent member (10) and covering an upper surface of the metal powder, and a lower lid constituent member (12) mounting on the other opening of the side constituent member (10) and covering a lower surface of the metal powder. The peripheral edges of the upper lid constituent member (11) and the lower lid constituent member (12) are,respectively, provided with a peripheral wall (11b, 12b) standing upright along an outer peripheral surface of the side constituent member, and the side constituent member (10) is inserted into a space surrounded by the peripheral wall (11b, 12b).

Abstract: A metal matrix composite material comprising a pair of metal plates having a powder mixture disposed therebetween forming an intermediate layer is disclosed. The powder mixture includes a metal powder and a ceramic powder. The ceramic powder has a neutron absorbing function and includes a B4C powder. The intermediate layer has a theoretical density ratio at least 98%, and a percentage of a total thickness of the metal plates to an overall thickness of the intermediate layer is in a range of 15 to 25% and the ceramic powder has a neutron absorption rate of at least 90%.

Abstract: A metal matrix composite material comprising a pair of metal plates having a powder mixture disposed therebetween forming an intermediate layer is disclosed. Each of the metal plates having a main wall with opposed lateral walls on each end. The first of the metal plates having a main wall having a length greater than a length of the main wall of the second of the metal plates, so that the opposed lateral walls of the second metal plate are each disposed inside of a respective opposed lateral wall of the first metal plate. The powder mixture includes a metal powder and a ceramic powder. The ceramic powder has a neutron absorbing function, wherein the intermediate layer has a theoretical density ratio at least 98%, and a percentage of a total thickness of the metal plates to an overall thickness of the intermediate layer is in a range of 15 to 25%.

Abstract: A method of producing an aluminum matrix composite material is described that comprises the steps of: mixing an aluminum powder and a ceramic powder to prepare a mixed powder; providing a lower casing made of aluminum and formed in a hollow rectangular parallelepiped shape having an open top, and a closing member made of aluminum and formed in a shape adapted to hermetically close the open top of the lower casing; packing the mixed powder into the lower casing; closing the open top of the lower casing filled with the mixed powder, by the closing member, to prepare a pre-rolling assembly having the mixed powder hermetically sealed therein; preheating the pre-rolling assembly; and rolling the preheated assembly to obtain the aluminum matrix composite material, where the aluminum matrix composite material includes a pair of metal plates having the mixed powder therebetween.

Abstract: A method of producing an aluminum matrix composite material is described that comprises the steps of: mixing an aluminum powder and a ceramic powder to prepare a mixed powder; providing a lower casing made of aluminum and formed in a hollow rectangular parallelepiped shape having an open top, and a closing member made of aluminum and formed in a shape adapted to hermetically close the open top of the lower casing; packing the mixed powder into the lower casing; closing the open top of the lower casing filled with the mixed powder, by the closing member, to prepare a pre-rolling assembly having the mixed powder hermetically sealed therein; preheating the pre-rolling assembly; and rolling the preheated assembly to obtain the aluminum matrix composite material, where the aluminum matrix composite material includes a pair of metal plates having the mixed powder therebetween.

Abstract: A method of producing an aluminum matrix composite material is described that comprises the steps of: mixing an aluminum powder and a ceramic powder to prepare a mixed powder; providing a lower casing made of aluminum and formed in a hollow rectangular parallelepiped shape having an open top, and a closing member made of aluminum and formed in a shape adapted to hermetically close the open top of the lower casing; packing the mixed powder into the lower casing; closing the open top of the lower casing filled with the mixed powder, by the closing member, to prepare a pre-rolling assembly having the mixed powder hermetically sealed therein; preheating the pre-rolling assembly; and rolling the preheated assembly to obtain the aluminum matrix composite material, where the aluminum matrix composite material includes a pair of metal plates having the mixed powder therebetween.

Abstract: A method for producing an aluminum composite material having a great content of a ceramics with ease. The method (a) mixes an aluminum powder and ceramic particles, to prepare a mixed material, (b) subjects the mixed material to electric pressure sintering together with a metal sheet material, to form a clad material including a sintered product covered with the metal sheet material, and (c) subjects the clad material to a plastic working to prepare an aluminum composite material. In the (b) subjecting, the mixed material is sandwiched between a pair of metal sheets or a powder of the mixed material is held in a metal container, the mixed material is placed in a forming die in a state in which the metal sheet material is pressurized by a punch, and the mixed material is compressed together with the metal sheet material. The metal sheet material is made of aluminum or stainless steel.

Abstract: Sintered pieces of rapid-solidified aluminum alloy powder are friction stir welded together. The sintered piece may be composite material dispersing ceramic particle therein. A welding aid, which disperses the same ceramic particle as those in the sintered pieces, may be sandwiched between or mounted on the sintered pieces. A weld zone is formed without melting, so as to inhibit formation of blowholes or coarsening of metallographic structure. Consequently, the sintered pieces are welded together while retaining intrinsic properties of the sintered aluminum alloy.

Abstract: A pedestal unit usable for a raised floor is disclosed which comprises: a pair of beams; and a pair of pedestal frames for supporting the beams at both ends of the beams, respectively. Each pedestal frame comprises: a pair of leg members; a pair of base plates for supporting the leg members; respectively, and a connecting member with a predetermined length for rigidly connecting the legs member each other with a predetermined interval. The pedestal frame may be installed under a middle portion of the beams, which frame may be installed after installation of pedestal frames at ends of beams for easy adjustment. Additional pedestal frames for supporting additional beams may be fixed to the pedestal frames or the beam. A supporting surface of leg member may have a mount provided by casting and be cut for accurate dimensions.