US2101892A - Water tube boiler - Google Patents

Description

DeC- 14, 1937. A. o. BLATCHFORD v 2,101,892

'WATER TUBE BOILER Y Filed June l, 1937 UNlTED STATES PATENT orrics WATER TUBE BOILER Albert Oliver Blatchford, Amballes, Guernsey,

Channel Islands l Application June 1, 1937, Serial No. 145,821

In Great Britain 2 Claims.

The chief object of the present invention is to provide a water tube boiler for the production of steam or hot Water, or a water heater for hothouse and domestic plant in which the maximum efliciency is obtained. In Water tube boilers in which the products of combustion are free to pass up between the parallel tubes a great deal of -eciency is lost owing to all or some of the products of combustion merely passing between laterally spaced tubes somewhat freely to the stack. And also if some of the conduits appropriate to the complete circuit of the tubes are outside the boiler shell, loss in efficiency arises due to radiation with the externally disposed parts whilst sluggishness in circulation occurs due to parts being directly exposed to cooling air. Another object -oi this invention is toprovide a water tube boiler in which the products of combustion are forced to traverse a Zig-zag ascending path along the tubes without the loss in efflciency arising out of parts of the tubes or conduits connecting the successive banks of tubes being outside the boiler shell or isolated from the influence of the ascending products of combustion.

In order that my invention may be clearly understood and readily carried into effect I have appended hereto a sheet of drawing, somewhat diagrammatic, illustrating embodiments thereof, and wherein:-

Fig. l is a sectional side elevation of a boiler,V

and

Fig. 2 is a detail sectional View showing a modied arrangement of baille plate.

Referring to the drawing the furnace is indicated by the reference numeral l and is disposed in the base of an outer shell (2) provided with a suitable furnace charging door or doors (3) and any suitable inspection cover or covers. The 4.0 water tubes (4) are arranged in bunches, four bunches, a, b, c, and d being shown merely by way of example, as any convenient number may be adopted. Each bunch of tubes consists of any suitable number of tubes arranged side by side for nearly the full transverse inner dimension of the shell (2), and also, although I have only shown one line of tubes for each bunch, a number of lines can be arranged close together, the tubes of successive lines preferably being staggered.

The ends of the tubes are engaged in headers 5, these headers being arranged in pairs joined by short ascending pipes 5, with of course the exception of the uppermost and lowermost headers which need only be single members. The

September 29, 1936 uppermost header is connected by a pipe 'l to the steam space of a drum 8, the latter conveniently being arranged vertically alongside the shell 2. The base of the drum is connected to the lowermost header by a pipe lil. The headers are located close to the front and rear walls of the shell 2 to avoid as much as possible large areas of idle space, and the shell 2 is preferably formed with transverse channels or pockets il opposite the headers to assist in guiding the products of combustion on the ascending circuitous path over the layer of each pair of headers and through the narrow horizontal space between each pair of headers as indicated by the arrows.

rIihe tubes are arranged at a very shallow angle of inclination so that they ascend in Zig-zag manner, and the products oi combustion follow such. a path, this result being assisted by baliles l2 of heat resisting material preferably laid upon the tubes 4 and having suilicient clearance at their ends to expand. After the products of combustion have traversed the tubes a, b and c such products escape through the spaces between the tubes of the upper set d into the flue I3.

If desired, a number of sets of tubes, arranged in the herebefore described manner, can be arranged alongside each other, on opposite sides of the said drum so that there are more than one lowermost header to be connected to the drum. Although I have described a vertical steam and Water drum it is of course understood that a horizontal drum can be adopted, the important feature of this invention being the arrangement of tubes and headers.

If desired the baliles l2 may each take the form of a pair of iron sheets l2a and i211 as shown in Fig. 2 Which rest loosely upon the tubes and overlap so as toprovide for expansion and contraction.

What I claim iszl. In a Water tube boiler or water heater, a plurality of sets of tubes arranged in a zig-zag manner, headers arranged transversely to the tubes and receiving the ends or the tubes,` said sealed in relation to the shell against free passage of products of combustion past it vertically.

2. In a water tube boiler or water heater, a plurality of sets of tubes arranged in a zig-zag manner, headers arranged transversely to the tubes and receiving the ends of the tubes, said headers being arranged in narrowly spaced pairs,

` short ascending conduits connecting each pair of headers, bales covering the upper sides of the 10 tubes for their full length, an outer shell totally

Images