US1681725A - Steam-heating system - Google Patents

Description

Aug. 21, 1928.

J. A. DONNELLY STEAM HEATING SYSTEM Filed June 18, 1924 54F l 1 \N\ M EWF INVENTOR. 7Z7/r7 5 D nne/W, BY

A? M ,1 3 WA TTORNEYS.

w ilk W WZPAVQ 3 AN aw 9? Patented Aug. 21, 1928.

UNITED STATES PATENT OFFICE.

JAMES A. DON'NELLY OF BROOKLYN, NEW YORK, ASSIGNOR T0 WABREE' WEBSTER &

COMPANY; A CORPORATION OF NEW JERSEY, I

STEAM-HEATING SYSTEM.

Application filed June 18, 1924. Serial 110,720,829.

This invention relates to regulating means for insuring the proper amount of steam to be supplied to heating systems and to the respective radiators thereof.

In commercial practice with installations involving distribution of steam to a large number of radiators, as in the case of hotels, apartment houses and oflice buildings, great difiiculties have been experienced in insuring proper distribution of the steam throughout all the radiators and in obtaining uniform temperature conditions, and these difiiculties have been increased owing to various conditions due to the character of the exposures (such as-northern and southern exposures) and causes due to shape of building Which induces abnormal air currents. With the radiators 4 inducing the necessary steam circulation therein, but such systems 1 have been costly to install and diflicult to keep in satisfactory operative condition. They also require constant attention, and, moreover, are incapable of varying the radiator heating capacity on the modulation prlnciple, and therefore required additional automatic thermostatically controlled means for alternately admitting and shutting off the supply of steam to each radiator to control the time periods in which it is acting as a heater to maintain the normal room temperature required. All of these difficulties are entirely overcome with my improved system in that a vacuum and vacuum creating means may be entirely dispensed With and the steam, which is delivered into the system, so subdivided as to supply the needs of the different portions of the distributing mains, pipes, rises ta, whereby it is delivered into the, radiators only in the'exact quantity required, the circulation thus produced insuring the exact predetermined results as to room temperature and, at the'same time, permit said room temperature to be varied to the desired extent at will, I 'whilenot exceeding the predetermined maximum temperature required. By the employ ment of my improvements, steam is sothoroughly subdivided and accurately distributed among all of the headers, risers and branch pipes, that each radiator may be definitely supplied with the required steam, whereby uniform temperature is automatically assured throughout the building, thus enabling a large system to be operated perfectly as a pressure system with the elimination of vacuum requirements and the attendant complicatlon of vacuum pumps and other apparatus pecuhar to vacuum systems.

One objectof the invention is to provide suitable means for distributing to radiators arranged in groups the proper proportion of steam necessary. therefor as an entirety, and also as required by the respective radiators of such groups, whereby the different-groups of radiators may operate to maintain a uniform temperature under different outside temperature conditions to which they may be respecjavely subjected during the same period of ime.

Another object of the invention is to provlde an improved apparatus for insuring the proper amount of steam to be fed to the radiators by controlling the steam supply and proportionally distributing the steam to respective groups of radiators and to the individual radiators of said groups in exactly the proper relative quantities to insure uniform heating of the building thereby.

Other objects of the invention are to improve generally the simplicity and efliciency of steam systems and to provide apparatuses of this kind which are economical to manufacture and operate and which are very easy to control. v

Still other objects of the invention will appear as the description proceeds; and while herein details of the inventionare described, the invention is notlimited to these since many and various changes may be made without departing'from the scope of the invention as claimed.

. The inventive features for the accomplishment of these and other objects are shown herein in connection with a heating system having, in addition to the usual large horizontal steam main into which the initial supply of steam is delivered, a plurality of branching mains or risers opening from the horizontal main at different distances from the source ofsteam supply, and a plurality of radiators forming separate groups severally receiving steam from the respective risers or branch mains and arranged at different distances from the connection of the risers or branch mains with the steam main, when characterized by having means for normally supplying the horizontal steam main with steam at a pressure above atmos' pheric pressure and in quantity less than sufii cient, in medium cold weather (such as 50 F, for example), to fill all the radiators, to gether with means having orifices of predetermined sizes respectively arranged in each of the risers or branching mains adjacent to their inlet ends and proportioned to regulate and supply steam from the horizontal main into the respective risers or branching mains in uantity (during saidmedium cold weat ier) insufficient to fill the grouped radiators in communication with the respective risers or branch mains, and separate means arranged between the individual radiators of each group and their respective risers or branching mains, each having an Orifice of predetermined size for regulating and nor" mally admitting, to the radiators of the respective groups, steam at or above atmosphcric pressure and in quantity insuflicient (during said medium cold weather) to completely fill the radiators, the orifices pertaining to the radiators of the several groups or several radiators of any group, differing in area to compensate for the different distances of the respective radiators of the groups from the horizontal main, by reason of which definite and proper distribution of steam is normally insured to the numerous radiators and.

uniform heating of large buildings made possible with a minimum consumption of steam which. in actual practice, has reach-ed a saving as high as fifty-seven per cent of the steam previously required in the most approved pressure and vacuum systems in general use.

My invention also comprehends other features of improvement which are fully set out hereinafter and defined in the claims.

In the accompanying drawing, showing by way of example, one of many possible embodiments of the invention,

Fig. 1 is a diagrammatic. side elevation of the system, the means for initially supplying the steam being shown partly in section;

Fig. 2 is a fragmental longitudinal sectional view. partly in elevation, of a conduit with the orificed disk therein;

Fig. 3 is a longitudinal sectional view of a union with the orificed disk therein for regulating the steam supplied to the risers and branch piping; and

Fig. 4 is a fragmental.diagrammatic sectional view of another form of steam. sup-plying means.

The steam is supplied from a boiler or any other suitable source to one or more horirisers 12 are fed by the supply main and in turn feed radiators 14. A control means 15 is interposed in said main for controlling and admitting to the main 11 the total quantity of steam required by the system. As shown this control means includes the valve 16, and flow orifice 17 with a pressure chamber 18 thcrebetwcen with which communicates the pressure gauge 19 controlled by the pressure in the pressure chamber for controlling the flow of steam.

The lower part of each respective riser is provided with an offset portion in which is interposed a union 26 (Fig. 3) provided with a disk 27 having therein an orifice 28 of a size calculated to compensate for the pressure drop due to friction alone of the horizontal distribution in the supply main 11 corresponding to the distance of the riser inlet from the control means 15 for admitting to each riser the proper proportion of steam required for the radiators fed thereby. While any suitable union 26 may be used, the one shown in Fig. 3 will answer the purpose. It

includes a threaded terminal 30 received on one section of the offset 25 and provided with an e'xteriorly threaded thickened inner end 31 having a transverse inner end face 32 leaving a large central opening 33. The terminal 30 may be provided with wrench received faces 34. A second terminal received on the other section of the offset is provided at its intermediate part with wrench receiving faces 41 and provided at the inner end with an outer shouldered flange 42 and a transverse end face 43. The disk 27 is secured between said terminal parts 30 and 41 and against said transverse faces 32 and 43. The central flow orifice 28may be formed with a lip 44 turned in the direction of flow of the steam. An interiorly threaded hexagonal ring 45 received on the threaded flange 31 and provided with an interior flange 46 engaging said shouldered flange 42, holds all of the parts firmly together, and is removable to permit interchange of the disks. A suitable disk 50- (Fig. 2) is also interposed between the respective radiators 14 and the associated risers 12 and is provided with an" orifice 51 for admitting to each radiator theproper proportion of steam for the respective radiators, each orifice being of a size calculated to compensate for the pressure change due (1) to the friction of the vertical distribution of steam in the risers corresponding to the distance of the radiator from the main 11, (2) to the decrease in atmospheric pressure due to altitude, and (3) to the decrease 'in pressure due to the weight of the steam.

WVhile the disks 50 may be interposed in many different ways, herein I show each radiator inlet valve 55 provided with an exteriorly threaded conduit 56 (Fig. 2) projecting from the side of the valve casing and provided with zontal supply mains 11. Branch pipes or a transverse partial partition 57 provided with an opening and an outer inwardly inclined face 58 receiving a coned edge face 59 of a terminal 60 exteriorly threaded at its outer end 61 for receiving a union and provided at its-intermediate part with wrench receving faces 62 and at the inner end with a shouldered flange 63, said inner end also provided with an inner shoulder 65 against which said disk is secured in the terminal 60. An interiorly threaded hexagonal ring 66 received on the threads of said conduit 56 and provided with an inward annular flange 67 engaging said shouldered flange, holds the parts firmly together, and is removable to permit interchange of the disks. Drip pipes 7 O drain the risers 12 into the return main 71 to which also return the branch return pipes 72 draining the radiators 14 through outlet pipes 74 and provided with air valves 75.

' From the foregoing it is evident that the attendant may, by the valve 16, control the proper total initial quantity of steam required for the system in accordance with outside weather conditions, and that the orifices 28 will control and admit to each group. of

radiators the proper proportion of steam required for the radiators thereof, while the orifices 51 will control and admit to each individual radiator the proper proportion of steam therefor. When the weather is very cold. the attendant will admit enough steam by valve 16 to heat the larger part or whole of. each radiator but when the weather is warmer, he will admit onlyanough steam to heat part of each radiator, the extent of the heat radiating surface being controlled in accordance with the amount of steam supplied to the whole system,a1id in accordance with the outside weather conditions, as above explained.

It is not only the object of this invention to provide a means for controlling the total amount of steam supplied to a heating system,.but also to distribute the steam equally among all individual radiators.

' Since the total amount of radiating surface provided for-heating a building is calculated for the lowest outside temperature condition, it follows that, for economical operation, the heating eflect of the radiators must be reduced for all milder weather conditions. This maybe done to a slight degree by reducin g the pressure and temperature of the steam or by reducing the quantity by hand manipulation of each radiator inlet valve. But I prefer to do it on a larger and more effective scale by controlling the quantity of steam ad,- mitted at the main supply, keeping the delivery pressure substantially constant, and then provide, firstly, means to regulate the proportionate flow of steam to each group. or section of the piping system, and secondly, to each radiator.

In my investigation as to the details of this problem, I discovered that in buildings of any considerable height it was necessary to take into account the variations in atmospheric pressure due to altitude. This led me to adopt a system of dividing the apparatus into groups, providing an orifice in each of the steam riser connections, so that with the total quantity of steam under proper and accurate control, a proper sub-division of this quantity can be effected to each riser. This allowed for an adjustment to compensate for the friction of the piping in the horizontal distribution of the steam. Orifices provided for each radiator were then calculated for the combined effect of the riser friction and the change in both atmospheric and steam pressure due to altitude. This calculation may readily be made by anyone familiar with the weights of the two fluids and the laws governing the flow of steam.

. However, as the difference between the weight of the column of steam and air is constant, while the difference in friction is as the square of the velocity, no correction can be made forthe combination ofthe two which .and lower atmospheric pressure at the top oft-he riser. In the latter, thehighest steam pressure and lowest air pressure are at the top of the riser, and the lowest steam pressure and highest air pressure are at the bottom of the riser. I

Where the source of steam supply is at low pressure, the quantity of steam may be controlled by keeping the pressure constant and varying the opening, or by providing a means of draft control, such as is shown in my application Serial No. 47 2,229 filed May 24, 1921.

Where the source of steam supply is at high pressure, I prefer to keep the orifice through which the steam i supplied of constant size and vary the pressure uponit, which may be done with the controlling means above described and shown in Fig. l. x

Where the steam supply is at low pressure, it may come either from a low pressure steam boiler or a low pressure street steam plant,

or it may be exhaust steam at low pressure.

manner. One of thefe control valves is placed in each of the branch mains 11 leading to a portion of the building, and each is adjusted in accordance with outside temperature and wind variations, to the proper amount of opening.

Where the steam supply is at high pressure, it may be either from high pressure boilers, or a high pressure street steam plant, or high presiure steam used to supplement the supply of exhaust steam. Under these conditions, a chamber is provided, equipped on the inlet with a special throttling valve, and on the' outlet with a calibrated flow nozzle or orifice. With a gauge to indicate the ressure on the chamber, the amount of steam furnished to the heating system through the flow nozzle is under very exact control of the operator for all varying demands of the heating system.

lVith either method of supply control, the fixed orifice with varying pressure, or varying orifice with fixed pressure, the sub-division of the steam to the various risers is the same. A controlling orifice plate is placed in the'union flange of each steam riser connection, the area of which is calibrated for the amount of steam required by the connected radiation, under the conditions of pre sure as affected by the friction drop of the steam main to each riser connection.

With either method of control, the main supply may be divided into several groups, and these may have more or less relation to the building exposure as well as to the points if compass.

l have found in my experience with this sy-tem, that building exposure due to its loca tion, as Well as points of compass, are very important factors to be considered in connec tion with the distribution of steam, and es pecially distribution of fractional quantities. The combination of a controlling orifice in a riser and a distribution orifice for each radiator makes it possible to change the amount of team supplied to a whole side of a building, hr to a particular section, by the correction in size of the riser orifice, without the necessity of changing the orifice disk for each radiator, which eliminates a considerable amount of work. In cases where additional radiation has to be added, the riser orifice only has to be changed, and not the individual radiator orifices, which would be the case if the control depended entirely upon a distribution orifice for each radiator, without the master con trolling orifice in the riser. This is also the case where errors are made in figuring the friction of the steam main, which may be due to an unusual combination of fittings or other causes.

No claim is made in this application for the method of supplying steam from the source to the radiators herein described.

I claim as my invention:

1. A steam'heating system, wherein there are associated and combined, a source of steam supply, a substantially horizontal steam main, a plurality of branching mains or risers respectively opening from the steam main at different distances from the source of steam supply, a plurality of groups of radiators of which a separate group is connected to each of the branching main or risers and receives steam therefrom, fixed orifices between the several radiators of each group and the respective branching mains or risers to cause the steam therefrom to be Supplied. to the radiators in predetermined quantities, means in communication with the source of steam supply for initially supplying the system as a whole with steam of a predetermined quantity required for all of the radiators thereof, means having orifices of predetermined area arranged in the respective branching mains between their connection with the radiators and the substantially horizontal steam main and each such orifice proportioned as to area to insure the passage of the predetermined quantity of the steam required by the radiators of the corresponding group.

2. The invention of claim 1, wherein further, the areas of the fixed orifices for the radiators increase per unit of heating capacity proportionally as said radiators are positioned more distantly from the orifices of the branching mains or risers which supply them with steam. 4

3. The invention of claim 1, wherein further, the areas of the fixed orifices of the branching mains or risers controlling the sup ply of steam to the respective radiator groups increase per unit of heating capacity proportionally as said radiator groups are positioned more distantly from the initial source of steam supply.

i. The invention of claim 1, wherein further, the means in communication with the source of steam supply for initially supplying the system as a whole with steam of a predetermined quantity comprises an expansion chamber, a flow orifice interposed be-' tween the expansion chamber and the substantially horizontal steam main of the system, and a control valve interposed between the expansion chamber and the source of steam for admitting steam to the expansion chamber at a greater pressure than maintained in the horizontal steam main to provide a predetermined differential across the flow orifice.

t Signed at New York, in the county of New York and State of New York, this 17th day of June, A. D. 1924.

JAMES A. DONNELLY.

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