Babcock & Wilcox Co. v. Springfield Boiler Co.

• Decision Date: 10 January 1927
• Docket Number: No. 102.,102.
• Citation: 16 F.2d 964
• Parties: BABCOCK & WILCOX CO. v. SPRINGFIELD BOILER CO. et al.
• Court: U.S. Court of Appeals — Second Circuit

16 F.2d 964 (1927)

BABCOCK & WILCOX CO. v. SPRINGFIELD BOILER CO. et al.

No. 102.

Circuit Court of Appeals, Second Circuit.

January 10, 1927.

Gifford & Scull, of New York City (Livingston Gifford, of New York City, C. P. Byrnes, of Pittsburgh, Pa., and George F. Scull, of New York City, of counsel), for appellant.

John E. Hubbell, of New York City, for appellee Springfield Boiler Co.

Briesen & Schrenk, of New York City (John E. Hubbell, W. Brown Morton, and Fritz v. Briesen, all of New York City, of counsel), for appellee Superheater Co.

Before HOUGH, MANTON, and MACK, Circuit Judges.

MANTON, Circuit Judge.

The appellant sues for infringement of claims 4, 6, 7, and 9 of the Bell patent, No. 1,141,520, granted June 1, 1915, and claims 1, 2, 4, and 6 of the reissue patent to Pratt, No. 15,210, granted October 18, 1921, which read as follows:

Bell Patent, No. 1,141,520.

"4. In a steam boiler, the combination, with longitudinally disposed upper and lower banks of tubes, of a transverse pass for the products of combustion having an upper restricted portion, and a superheater located in the lower larger portion of said pass."

"6. In a steam boiler, the combination, with longitudinally disposed upper and lower banks of tubes, of a transverse upward pass for the products of combustion, across the tubes having an upper restricted portion, a downward transverse pass across the tubes communicating with the upward pass and having a restricted lower portion, and a superheater located in the lower larger portion of the upward pass.

"7. In a horizontal water tube boiler, the combination, with upper and lower banks of water tubes, of a furnace located below the same, transversely disposed baffles to cause the products of combustion to flow upwardly across the tubes, and a superheater arranged in one of the passes formed by the baffles, said pass being constricted above the furnace."

"9. In a horizontal water tube boiler, the combination, with a substantially horizontal set of water tubes, of a furnace located below the same, oppositely extending transversely disposed baffles arranged across the tubes and producing up and down passes, one of said baffles having an offset to produce a constriction in the first pass and also in the second pass, and a superheater arranged in the first pass and above the furnace."

Pratt Reissue, No. 15,210.

"1. A water tube boiler having longitudinal water tubes, a superheater having transversely extending bent tubes between the water tubes, and baffling for directing the products of combustion, said baffling having a horizontally extending baffle above the lower water tubes to expose them to the flame and gases for the major portion of their length, and an upwardly projecting baffle extending therefrom transversely of the water tubes above the superheater, and arranged to give the gases a restricted upward transverse pass across the water tubes located above the superheater.

"2. A water tube boiler having front and rear water compartments connected by longitudinal horizontally extending water tubes, a superheater having transversely extending tubes between the water tubes, with bent portions within the setting, and baffling for directing the products of combustion, said baffling having a baffle extending in a horizontal direction along the lower rows of the water tubes located above the superheater, to expose the water tubes below the superheater to the flame and gases for the major portion of their length, and an upwardly projecting baffle extending therefrom transversely of the water tubes above the superheater, and arranged to give the gases a restricted upward transverse pass across the water tubes located above the superheater."

"4. A water tube boiler having water compartments connected by longitudinal horizontally extending water tubes, a superheater having transversely extending tubes between the rows of water tubes and provided with bent or curved portions, and baffling for directing the products of combustion, said baffling having a horizontally extending portion among the water tubes over the superheater, and also having a portion extending upwardly and transversely of the water tubes above the superheater, said baffling forming an upward transverse pass for the gases which is narrower among the water tubes above the superheater than at the inlet to the water tubes below the superheater, the lowermost water tubes being exposed to the flame and gases for the major portion of their length."

"6. A water tube boiler having water compartments connected by longitudinal horizontally extending water tubes, a superheater having transversely extending tubes between the rows of water tubes and provided with bent or curved portions within the setting, and baffling for directing the products of combustion, said baffling having a horizontally extending portion among the water tubes over the superheater, and also having a portion extending upwardly and transversely of the water tubes above the superheater, said baffling forming an upward transverse pass for the gases which is narrower among the water tubes above the superheater than at the inlet to the water tubes below the superheater and to the superheater, and another baffle depending among the upper water tubes and extending transversely of them arranged to give the gases another transverse down and up pass through said upper water tubes."

Both appellant and the Springfield Boiler Company, appellee, are manufacturers of boilers, and the Superheater Company, appellee, is a manufacturer of superheaters. The infringement relied upon occurred in the construction of the boiler at the Hell Gate station of the United Electric Light & Power Company of New York City. The user is not joined as a party. The court below held that the appellees did not infringe.

The boilers are used to furnish power to turbines for driving electric generators of central stations. Enormous power is required, involving the use of superheated steam at high temperature, which must be kept within a narrow range to avoid injuring the turbines. There are two classes of water tube boilers, vertical and horizontal. In the horizontal water tube boilers, the tubes are usually slightly inclined to the horizontal and extend into headers or water boxes at their ends, which water boxes are connected to an upper steam or water drum. In the upper steam or water drum, the water is maintained at a level intermediate the mouth of the drum. Steam is generated by heat applied to the water tubes, and the steam and water circulate through the tubes and pass up to the steam and water drum, where the same is liberated and is held under pressure in the steam space. The unvaporized water passes back into the circulation, together with the fresh water fed in, and the steam is taken to the superheater. The superheater is a tubular structure, through which the steam passes from the steam and water drum; the superheater being also subjected to heat so as to raise the temperature of the steam and increase the efficiency of the engine or turbine which it drives. This created a demand for high and uniform superheat. With low superheat, the wet steam caused raindrops, which injured the turbine blades, and with too high superheat the high temperature would injure the plates. It was found in practice that the temperature should approach a red heat, and not rise too far or drop below this.

At the time Bell made his invention, the standard boiler used had a single bank of horizontally inclined water tubes extending between heaters connected to a steam and water drum, from which the steam passed into a superheater located above the bank of tubes and between this bank and the steam and water drum. It had a short furnace, extending only part of the length of the water tubes to a bridge wall. The gases were directed along the tubes by baffling, which was made of tiles extending transversely of the tubes, and caused the flame and gases to rise through the first pass, then down through the second pass, and thence up through the third and last pass. The superheater was in the triangular space above the water tubes and below the drums, so that the gases were cooled down very considerably by passing over the water tubes before they reached the superheater. Arrangement was made for flooding the superheater tubes with water to protect them against burning out, and various kinds of reflectory valves were used for shielding off part of the gases contacting with the superheater tubes. Thus care was used to prevent overheating of the superheated tubes. There were nine rows of water tubes, and the boilers were sometimes driven up to 1½ or 2 times their rated capacity.

It was the peak loads, increased as the demand for electric power advanced, that caused engineers at this time to attempt to fill the demand for bigger and higher units and higher superheats. Bell designed a higher boiler with an unusual number of rows of water tubes, and increased correspondingly the amount of coal burned by adopting full fire in place of half firing. He relocated the superheater from its old position in the triangular space above the tubes down into the interdeck position between the banks, and thus attained compactness of the entire boiler and superheater without increasing the size of the setting. Other efforts of patentees proposed doing away with all baffling, giving the flame and gases one pass over the bank of tubes and to place the superheater between some of the rows of tubes in the interdeck position. But the gases did not flow back over the water tubes and the superheater had to be either within the bank of water tubes or beyond it at the outlet flue.

This inventor conceived correctly that proper efficiency required the use of baffling. Single pass boilers did not become practical, nor were they used in this art. To obtain efficiency of his new boiler, this patentee adopted the transverse type of baffling...