Abstract: A refrigerant jacket includes a refrigerant cooling member, a cover member and a strength member. The cooling member is constructed of aluminum or aluminum alloy that thermally contacts a heat emitting electrical part, and has a groove portion. A refrigerant tube of a refrigerant circuit fits into the groove portion. The cover member covers the refrigerant cooling member in a state where the refrigerant tube has been fitted into the groove portion. The strength member is higher in strength than the cooling member, and is fixed to the cooling member. The cover member has a cover-side through hole opposing the strength member. The strength member has a cover member fixing screw hole opposing the cover-side through hole. The cover member is fixed to the strength member by a cover member fixing screw that passes through the cover-side through hole and screws into threads of the cover member fixing screw hole.

Abstract: A refrigerant jacket includes a refrigerant cooling member, a cover member and a strength member. The cooling member is constructed of aluminum or aluminum alloy that thermally contacts a heat emitting electrical part, and has a groove portion. A refrigerant tube of a refrigerant circuit fits into the groove portion. The cover member covers the refrigerant cooling member in a state where the refrigerant tube has been fitted into the groove portion. The strength member is higher in strength than the cooling member, and is fixed to the cooling member. The cover member has a cover-side through hole opposing the strength member. The strength member has a cover member fixing screw hole opposing the cover-side through hole. The cover member is fixed to the strength member by a cover member fixing screw that passes through the cover-side through hole and screws into threads of the cover member fixing screw hole.

Abstract: A pulverized coal-fired boiler efficiently supplies air to a central part of a furnace and the neighborhood of a furnace wall, thereby promoting mixture with combustion gas, and reducing both NOx and CO. The main after air ports are structured so as to jet air having a large momentum for enabling arrival at the central part of the furnace, and the sub-after air ports are structured so as to jet air having a small momentum to the neighborhood of the wall face of the furnace, and a sectional center of each of the sub-after air ports is within a range from 1 to 5 times of a caliber of the main after air ports from a sectional center of each of the main after air ports.

Abstract: A pulverized coal-fired boiler efficiently supplies air to a central part of a furnace and the neighborhood of a furnace wall, thereby promoting mixture with combustion gas, and reducing both NOx and CO. The main after air ports are structured so as to jet air having a large momentum for enabling arrival at the central part of the furnace, and the sub-after air ports are structured so as to jet air having a small momentum to the neighborhood of the wall face of the furnace, and a sectional center of each of the sub-after air ports is within a range from 1 to 5 times of a caliber of the main after air ports from a sectional center of each of the main after air ports.

Abstract: A pulverized coal-fired boiler efficiently supplies air to a central part of a furnace and the neighborhood of a furnace wall, thereby promoting mixture with combustion gas, and reducing both NOx and CO. The main after air ports are structured so as to jet air having a large momentum for enabling arrival at the central part of the furnace, and the sub-after air ports are structured so as to jet air having a small momentum to the neighborhood of the wall face of the furnace, and a sectional center of each of the sub-after air ports is within a range from 1 to 5 times of a caliber of the main after air ports from a sectional center of each of the main after air ports.