A cooling channel structure includes a tubular member with openings at both ends. In an inner portion or on a surface of the tubular member, as cooling channels for flowing a cooling medium for cooling the tubular member, provided are a plurality of spiral outer surface-side channels located on an outer surface side of the tubular member, at least one inner surface-side channel located on an inner surface side of the tubular member, and a plurality of folded channels, respectively, connecting the plurality of outer surface-side channels and the at least one inner surface-side channel on one end side of the tubular member.

A gas furnace is provided. The gas furnace includes a combustion part in which a fuel gas is burnt to generate a combustion gas, a heat exchanger having a gas flow path through which the combustion gas flows, a blower configured to blow air around the heat exchanger, and an inducer configured to discharge the combustion gas from the heat exchanger. The heat exchanger includes at least one single path in which a single gas flow path is formed a single-multiple return bend configured to communicate with the single path and convert a flow direction of the combustion gas, and at least one multiple path having a plurality of paths that communicate with the single-multiple return bend and form multiple gas flow paths.

A heat exchanger for heating a fluid flowing through a pipe using a combustion gas includes: a body including open upper and lower ends and having a space formed therein to allow the combustion gas to pass therethrough; a combustor formed in an upper portion of the space in which combustion of the combustion gas occurs; a heat exchange portion formed below the combustor and provided with a heat exchange pipe configured to heat an internal fluid by using the combustion gas; and a heat return pipe provided outside the space so as to be in contact with an outer surface of the body, wherein the combustor and the heat exchange portion may be unitarily formed, and the body in which the combustor is formed includes a concave portion protruding concavely inward so as to correspond to a shape of an outer circumferential surface of the heat return pipe.

The present subject matter relates to a smoke tube boiler including: a mix chamber, a heat exchanger, a firing rod assembly, a sealing means, and an air-cooled cooling means and a water-cooled cooling means.

The notched base ring comprises a base ring sheet body including a top portion, a bottom portion, a first end connecting the top portion to the bottom portion, and a second end connecting the bottom portion to the top portion. The top portion includes a plurality of attachment lugs and defines a plurality of notches, each notch being at least partially defined by two lugs disposed on opposite sides of the notch, the top portion also including an angled top edge that is disposed at each of the attachment lugs, and the bottom portion includes a bottom support edge.

In a water heater provided with an inlet pipe a downstream end of which is connected with an upstream end of a water heating channel of a heat exchanger for producing hot water, an outlet pipe an upstream end of which is connected with a downstream end of the water heating channel, and a bypass pipe branching at a part of the inlet pipe, which is positioned at an upstream-end part away from an upstream end, and is connected with a part of the outlet pipe, which is positioned at a more downstream part than at an upstream end, a connecting part of the bypass pipe with the outlet pipe and another connecting part of an inlet pipe and the upstream end of the water heating channel are arranged at a same height in a setting state of the water heater.

A heat exchanger includes: a casing into which heating gas is supplied; and a plurality of heat transfer tubes which are arranged in the casing, wherein the plurality of heat transfer tubes are set in a posture in which a plurality of straight tube portions are arranged in a direction intersecting a heating gas flow direction, are stacked a plurality of stages in the heating gas flow direction, and are distinguished into first and second heat transfer tubes respectively located on an upstream side and a downstream side in the heating gas flow direction, and wherein the second heat transfer tube is formed so that an outer diameter of the tube and an arrangement pitch of the plurality of straight tube portions are smaller than those of the first heat transfer tube.

A tube profile (1), in particular for manufacturing a heat exchanger for a condensing boiler, wherein the cross-section (10) of the tube profile (1) comprises: a rectangular portion (20) having two greater sides (21, 22) parallel to each other and two smaller sides (31, 32) parallel to each other and orthogonal to the greater sides (21, 22), and an ogival portion (40) defined by a convex flat figure formed by a base (41) and two curved sides (42, 43) connected to each other in an apical zone (48) opposite to said base, wherein said base (41) coincides with a first side (31) of said two smaller sides (31, 32) of the rectangular portion (20), wherein said two curved sides (42,43) are symmetrical to an axis of symmetry (S-S) parallel to said greater sides (21, 22) and passing through the central points (33, 34) of said smaller sides (31, 32), wherein one end of each of said two curved sides (42, 43) joins to one end of a respective one of said two greater sides (21, 22)) in a first joining point (PH1), said each of said two curved sides (42, 43) being tangent to said respective one of said two greater sides (21, 22) in said first joining point (PH1), and wherein an overall dimension of said ogival portion (HO) measured along said axis of symmetry (S-S) is greater than the length of said base (41); wherein the two greater sides (21, 22), a second side of said two smaller sides (32), and said two curved sides (42, 43), define the outer surfaces (50) of the walls of said tube profile (1).

The present disclosure relates to a wavy smoke tube structure of a boiler, which improves heat exchange efficiency of a smoke tube. The wavy smoke tube structure includes: a main body formed in a columnar shape and having a space therein; a plurality of first concave portions concavely formed along a first side portion in a longitudinal direction of the main body; a plurality of second concave portions concavely formed along a second side portion in the longitudinal direction of the main body opposite to the first side portion and each positioned between a pair of the first concave portions to face them; and a plurality of blocking grooves formed in a pair of sidewall portions provided between the first side portion and the second side portion.

A cleaning system includes an explosive subsystem including: a plurality of detonation cords extending along a direction different from a vertical direction; and a locating assembly locating the plurality of detonation cords relative to each other. The locating assembly spaces each of the detonation cords apart from a system to be cleaned. The cleaning system includes a pressurized air blower assembly adjacent a portion of the system to be cleaned, the pressurized air blower assembly being configured to direct pressurized air towards the portion of the system to be cleaned after the detonation cords have been exploded.