An axial flow baffle for a shell and tube heat exchanger includes a substantially planar body configured for transverse arrangement in a longitudinally elongated shell of the shell and tube heat exchanger, a plurality of axial flow tube apertures each comprising a central tube hole configured to receive a tube of the heat exchanger, and an array of peripheral primary flow holes circumferentially spaced apart around the tube hole. The primary flow holes each interrupt the central tube hole and formed a radially inward projecting tube support protrusions between the primary flow holes which engage a single tube. Each primary flow hole has a non-polygonal configuration, which may be semicircular in some embodiments. The primary flow holes create axial flow around the periphery of the tubes through the baffles. In another aspect, a hybrid cross-flow baffle includes a combination of axial flow tube apertures and circular tube support holes.

An axial flow baffle for a shell and tube heat exchanger includes a substantially planar body configured for transverse arrangement in a longitudinally elongated shell of the shell and tube heat exchanger, a plurality of axial flow tube apertures each comprising a central tube hole configured to receive a tube of the heat exchanger, and an array of peripheral primary flow holes circumferentially spaced apart around the tube hole. The primary flow holes each interrupt the central tube hole and formed a radially inward projecting tube support protrusions between the primary flow holes which engage a single tube. Each primary flow hole has a non-polygonal configuration, which may be semicircular in some embodiments. The primary flow holes create axial flow around the periphery of the tubes through the baffles. In another aspect, a hybrid cross-flow baffle includes a combination of axial flow tube apertures and circular tube support holes.

Herein a boiler tube (2) having a longitudinal extension (L) and comprising radially inner and outer tubular portions (4, 6) extending along at least a first part (5) of the longitudinal extension (L). The radially outer tubular portion (6) is metallurgically bonded to the radially inner tubular portion (4). A sensor space (8) is arranged between the radially inner tubular portion (4) and the radially outer tubular portion (6), wherein the sensor space (8) is configured to accommodate a sensor arranged to detect a physical property of the radially outer tubular portion (6). A duct (10) is connected to the sensor space (8) and extends through the radially outer tubular portion (6) to an exit portion (12) of a surface of the radially outer tubular portion (6). The radially inner and outer tubular portions comprise materials of different chemical composition. Also, a boiler tube unit and a furnace are disclosed herein.

A package multiple pass flexible water tube boiler for converting water to steam. The boiler having an enclosure and diagonally offset upper and lower drums. The drums are connected by a series of staggered or offset water tubes. The water tubes comprise two sets of repeating tubes that are bent to substantially similar but not identical designs. The staggered tube arrangement optimizes heat transfer and minimizes the footprint of the unit.

A package multiple pass flexible water tube boiler for converting water to steam. The boiler having an enclosure and diagonally offset upper and lower drums. The drums are connected by a series of staggered or offset water tubes. The water tubes comprise two sets of repeating tubes that are bent to substantially similar but not identical designs. The staggered tube arrangement optimizes heat transfer and minimizes the footprint of the unit.

An axial flow baffle for a shell and tube heat exchanger includes a substantially planar body configured for transverse arrangement in a longitudinally elongated shell of the shell and tube heat exchanger, a plurality of axial flow tube apertures each comprising a central tube hole configured to receive a tube of the heat exchanger, and an array of peripheral primary flow holes circumferentially spaced apart around the tube hole. The primary flow holes each interrupt the central tube hole and formed a radially inward projecting tube support protrusions between the primary flow holes which engage a single tube. Each primary flow hole has a non-polygonal configuration, which may be semicircular in some embodiments. The primary flow holes create axial flow around the periphery of the tubes through the baffles. In another aspect, a hybrid cross-flow baffle includes a combination of axial flow tube apertures and circular tube support holes.

A package multiple pass flexible water tube boiler for converting water to steam. The boiler having an enclosure and diagonally offset upper and lower drums. The drums are connected by a series of staggered or offset water tubes. The water tubes comprise two sets of repeating tubes that are bent to substantially similar but not identical designs. The staggered tube arrangement optimizes heat transfer and minimizes the footprint of the unit.

A package multiple pass flexible water tube boiler for converting water to steam. The boiler having an enclosure and diagonally offset upper and lower drums. The drums are connected by a series of staggered or offset water tubes. The water tubes comprise two sets of repeating tubes that are bent to substantially similar but not identical designs. The staggered tube arrangement optimizes heat transfer and minimizes the footprint of the unit.