Abstract: A semi-modular rotor module for an air preheater having a circular rotor includes a lug assembly having a lug front, a lug back spaced radially outward from the lug front, and cold end and hot end lug members. The lug front and lug back each extend longitudinally from a first end to a second end, with the cold end lug member being mounted to the first ends of the lug front and the lug back and the hot end lug member being mounted to the second ends of the lug front and the lug back. A single main diaphragm extends radially from an inner end portion to an outer end portion, with the inner end portion being mounted to the lug front on a first side of the lug assembly. The outer end portion is mounted to a rotor shell which is spaced radially outward from the lug back. At least one intermediate diaphragm extends radially from an inner end portion, mounted to the lug back at a position intermediate the first and second sides of the lug assembly, to an outer end portion mounted to the rotor shell.

Abstract: A method for constructing a rotor of an air preheater having a plurality of diaphragm plates dividing the rotor into a number of wedge-shaped compartments. Each compartment includes compartment components such as a rotor shell plate, a hot end rotor angle, a cold end rotor angle, and one or more stay plates and means for locating at least a portion of each of the components within the compartment. The diaphragm plates are manufactured by marking at least one index location associated with each compartment component on each diaphragm plate blank utilizing a template identifying the index locations and forming an opening at each index location. Each compartment is assembled by positioning a first diaphragm plate adjacent to a second diaphragm plate and locating each compartment component between the adjacent diaphragm plates by engaging the locating means of the component in an associated opening in one of the diaphragm plates.

Abstract: A bypass seal for a rotary regenerative air preheater includes primary and secondary seal leaves that are joined at a single position longitudinally intermediate their first and second sends. The first end portion of the primary seal leaf extends longitudinally beyond the first end of the secondary seal leaf and the second end portion of the secondary seal leaf extends longitudinally beyond the second end of the primary seal leaf. When installed in the air preheater, the first end portion of the primary seal leaf of each bypass seal in one of the seal rings overlaps the second end portion of the secondary seal leaf of an adjacent bypass seal in the seal ring.

Abstract: A bypass seal for a rotary regenerative air preheater includes primary and secondary seal leaves that are joined at a single position longitudinally intermediate their first and second sends. The first end portion of the primary seal leaf extends longitudinally beyond the first end of the secondary seal leaf and the second end portion of the secondary seal leaf extends longitudinally beyond the second end of the primary seal leaf. When installed in the air preheater, the first end portion of the primary seal leaf of each bypass seal in one of the seal rings overlaps the second end portion of the secondary seal leaf of an adjacent bypass seal in the seal ring.

Abstract: A method for constructing a rotor of an air preheater having a plurality of diaphragm plates dividing the rotor into a number of wedge-shaped compartments. Each compartment includes compartment components such as a rotor shell plate, a hot end rotor angle, a cold end rotor angle, and one or more stay plates and means for locating at least a portion of each of the components within the compartment. The diaphragm plates are manufactured by marking at least one index location associated with each compartment component on each diaphragm plate blank utilizing a template identifying the index locations and forming an opening at each index location. Each compartment is assembled by positioning a first diaphragm plate adjacent to a second diaphragm plate and locating each compartment component between the adjacent diaphragm plates by engaging the locating means of the component in an associated opening in one of the diaphragm plates.

Abstract: A method for constructing a rotor of an air preheater having a plurality of diaphragm plates dividing the rotor into a number of wedge-shaped compartments. Each compartment includes compartment components such as a rotor shell plate, a hot end rotor angle, a cold end rotor angle, and one or more stay plates and means for locating at least a portion of each of the components within the compartment. The diaphragm plates are manufactured by marking at least one index location associated with each compartment component on each diaphragm plate blank utilizing a template identifying the index locations and forming an opening at each index location. Each compartment is assembled by positioning a first diaphragm plate adjacent to a second diaphragm plate and locating each compartment component between the adjacent diaphragm plates by engaging the locating means of the component in an associated opening in one of the diaphragm plates.

Abstract: The rotor of an existing rotary regenerative air preheater is retrofitted with deeper cold end baskets for general performance enhancement and/or for the tolerance of ammonium bisulfate deposits. the normal cold end support gratings are removed and the support of the cold end baskets of increased depth is at least partially from the existing rotor stay plates.

Abstract: The gas flow bypass around the heating elements in a regenerative air preheater is reduced by the use of floating bypass seals which are placed in the rotor compartments between stacked heating elements. The seals comprise a frame with an open center with the peripheral frame portion bridging the gaps between the heating elements and the sides of the compartments. The seals may be adjustable and may include a deformable edge seal to actually contact and seal against the sides.

Abstract: An air preheater has heat transfer elements with a first series of corrugated elements having longitudinally oriented, mutually parallel corrugations formed generally continuously across the lateral direction. Positioned on either side of each of the corrugated elements of the first series are a series of notched plates each having mutually parallel spaced apart notches. Each notch is formed by parallel double ridges projecting transversely from opposite sides and the element has flat sections between the notches. The notches are oriented obliquely in mutually opposite directions relative to the corrugations of the adjacent elements whereby the notched elements are in contact with the corrugated elements solely at the points of intersection of the notches and corrugations. This produces an increased number of boundary layer breaks and improves heat transfer as well as providing straight line passages through the elements.

Abstract: Ceramic blocks which may be catalyst coated having gas flow channels therethrough are supported in a metal framework to form a removable basket for a rotary regenerative air heater. The blocks are supported between compressed packing material with individual rows being supported at one inlet edge and the opposite outlet edge by Z-plates.

Abstract: An element basket for a rotary regenerative heat exchanger having an array of heat absorbent plates that comprise heat transfer elements therefor. Retaining means are affixed at opposite ends to basket walls to positively position the element plates within the basket. The element plates have curved recesses at opposite ends thereof to receive the retaining means, the recesses having a dimension greater than that of a transverse section of the adjacent retaining means to permit freedom of movement therebetween and to preclude a concentration of stresses that would effect premature failure thereof.

Abstract: A concentric tube type recuperative heat exchanger that includes an outer transparent tube 22 and an inner metallic tube 24 connected to suitable headers 12 and 14. The outer tube 24 is closed at the bottom end and open at the top end in order that cool air may be directed down through the open ended inner tube and up through the annular space therebetween where it may accept radiant energy transmitted through transparent tube 22. A tubular heat shield 36 of apertured metal lying in the annular space between tubes absorbs radiant heat passing directly through transparent tube 22 and that which is reflected from inner tube 24. Shield 36 serves simultaneously as a means for increasing the turbulence of fluid flowing through the annular space between tubes and as a heat sink that absorbs heat radiated between tube walls.

Abstract: A tool assembly for forming internal threads on the interior surfaces of tubular structures which comprises a substantially cylindrical tool holder defining circumferentially about one end thereof, a plurality of disc-shaped forming edges, said tool holder adapted for rotational contact with a tubular workpiece, a rotating means located in operative contact with said tool holder, said rotating means situated for longitudinal reciprocation along an inclined track, a workpiece securement means comprising opposed clamps or the like located on a base structure and adapted to secure said workpiece in axial alignment with said tool holder, and a track comprising paired track members or rails associated with said workpiece securement means, wherein said securement means and said track are inclined with respect to the horizontal whereby said workpiece is apically situated with respect to said track to enable said tool holder to traverse the interior of said workpiece while moving on said track.

Abstract: The present invention comprises (1) a heat source, (2) a heat pipe, and (3) a thermal transformer in thermal contact with said heat pipe and proximately disposed to said heat source, whereby a uniform heat transfer from said heat source to a heating system is obtained. The thermal transformer includes (1) a container, (2) a working fluid and its vapor which are essentially in equillibrium, (3) evaporating surfaces depending from the internal surfaces of the transformer that are wetted with the working fluid and that are proximate to the heat source, and (4) condensing surfaces depending from the exterior of those areas of said heat pipe that are in thermal contact with said transformer.