US1210784A - Steam-heating apparatus. - Google Patents

Description

LL, FITTS. STEAM HEATING APPARATUS.

APPLICATION TILED JAN. 5. .1910.

1,210,?8. Patented Jan. 2,1917.

WITNESSES barren sraras rare anion.

JAMES L. FITTS, 0F MERCHANTVILLE, NEW JERSEY, ASSIGNOR TO WARREN WEBSTER & COMPANY. A CORPORATION OF NEW JERSEY.

STEAM-.HEATIN G APPARATUS.

Specification of Letters Patent.

Patented J an. 2, 19 17.

To all whom it may concern:

Be it known that I, JAMES LOGAN Frr'rs, a citizen of the United States, and resident of Merchantville, county of Camden, Pensauken township, and State of New J ersey, have invented an Improvement in Steam- Heating Apparatus, of which the following is a specification.

My invention has reference to steam heating apparatus and consists of certain improvements which are fully set forth in the following specification and shown in the accompanying drawings which form apart thereof.

My invention has particular reference to steam heating apparatus of the low pressure type in which the water is returned to the boiler by gravity; and the object of my invention is to provide means which shall automatically, during the normal operation of the heating system, permit the escape of air to the atmosphere, but which will prevent the escape of water of condensation from the apparatus in case of abnormal operating conditions, such as an excessive boiler pressure existing in the system.

More specifically, the object of my invention is to rovide a gravity system of steam heating wli tion is adapted to permit the air from the system to escape but without loss of steam or water, and to maintain these results irrespective of abnormal temporary conditions in the steam pressure of the boiler.

The object of my invention may therefore be stated to provide means which will automatically cause the steam heating apparatus to provide a constant differential between the pressure in the steam supply and the return pipe, said constant differential maintaining a definite static head on the return side, even where the steam pressure in the boiler is reasonably varied.

My invention consists of certain improvements which are fully described hereinafter and more particularly defined in the claims.

Referring to the drawings: Figure 1 IS a diagrammatic elevation of a steam heating apparatus embodying my invention; and Fig. 2 is a sectional elevation of the automatic control valve thereof.

2 is the boiler, and 3 are the steam mains leading therefrom and extending upward through the building in the form of users ich at all times in normal opera- 6 are return pipes leading from the vari- I ous radiators or coils and are arranged to discharge at the bottom into a receiving tank 10 located at an elevation above the normal water line of the boiler 2. From the bottom of the receiving tank 10 the water is returned to the boiler by a pipe 9 connecting with its lower part directly or through a check valve structure 8, which permits the flow of water into the boiler, but prevents the flow in the reverse direction. Some times check 'valves are employed, and at other times they are omitted and in this latter case the communication between the boiler and the tank 10 is free and open.

7 are automatic valves of any suitable character for permitting the passage of air and water from the radiators 4 into. the return pipes 6, but preventing orrestricting the passage of steam. Numerous types of automatic valves adapted to steam heating apparatus are found upon the market, and any of these may be employed for the purposes of the valves 7, with my improvements. Opening from the upper part of the tank 10 is a vent pipe 11, preferably terminating in a check valve 12, said valve operating to permit the escape of the air from the tank 10 and consequently from the heating system, and at the same time preventing the inflow of air in case of a partial vacuum from any cause, such as when turning steam into cold radiators.

13 is an automatic valve arranged in the pipe 11 and preferably between the tank 10 and the check valve 12, which operates automatically to permit the escape of air, but prevents the escape of water, and therefore performs the function of retaining the water within the system, if from any abnormal cause the water tends to flow from the vent pipe into the atmosphere. The construction of this automatic valve 13 is shown in, Fig.

2, and comprises a thoroughfare 17 arranged inthe vent pipe 11 and controlled by the valve piece 18. The valve piece 18 1s secured to a diaphragm 15 arranged between two chambers 19 and 20, the former being in communication with the tank 10 through a portion of the vent pipe 11, and the latter being in communication with the steam supply ipe 3 by means of a small pipe 14. Normal y, the chamber 20 is kept full of water so that the steam from the pipe 3 does not directly act upon the diaphragm 15 but upon the body of water within the chamber 20, and therefore indirectly upon the diaphragm. The diaphragm 15 is also connected to a rod 21, working through a stuffing box in the bottom of the valve device, and said rod is hinged at its lower part to a counter-balance lever 16 having adjustable weights which permit of any degree of adjustment necessary. This weighted lever acts as a mechanical device for adjusting the normal pressure, upon the diaphragm 15, so that it shall properly respond to the de sired differential in pressures of the steam pipe 3 and the tank 10 or return pipe.

In the normal operation of the heating system, the level of the water in the tank 10 is above the level of the water in the boiler 2 sufiiciently to provide a static head to counterbalance the steam pressure carried in the boiler, and this may be, for example, 1% lbs.', or any other low pressure, such as employed in low pressure steam heating systems. During the normal operation of the apparatus, the air is driven from the radiators 4 by the inflowing steam whose supply is regulated by the modulation valves 5, and said air finds its way through the return pipe 6 into the receiving tank 10, and thence through the vent pipe 11, valve 13 and check valve 12, into the atmosphere. The water of condensation, which is produced within the radiators, is automaticall permitted to flow from the radiators into t e return pipes 6 by the automatic valves or traps 7, whenever said water accumulates. This water of condensation flows through the return pipes into the tank 10 and thence by reason of the static head, returns to the boiler. Should, however, the system become deranged from its normal condition of operation, such for instance, as by too much pressure in the boiler, there will be danger of the water from the receiver tank 10 being forced outward through the vent pipe 11 into the base ment or upon the floor of the building, pro ducing not only an objectionable mess, but a more serious loss of water from the heating system and a variation of the differential between the steam supply and return sides of the system. This latter condition is particularly objectionable in an automaticgravity system, which is usually given but little attention. Whenever the boiler pressure increases abnormally, the water is not permitted to flow from the receiving tank 10 into it, because of the internal pressure which keeps the check valve device 8 closed; and consequently, the water of condensation passing from the radiatorsinto the tank 10 will fill the said tank and overflow through the pipe 11 if not otherwise prevented. Where the check valve device 8 is not employed, then the abnormal boiler pressure will force the water from the boiler through the pipe 9 into the tank 10 and thence outward through the vent pipe 11 if not prevented. The -abnormal loss of water from any of these causes is liable to produce dangerous conditions in the system and a derangement of the normal working thereof.

By employing the automatic control valve 13 in the vent pipe 11, means is provided for maintaining the normal differential due to the static head and for automatically preventing the escape of water from the heating system under any of the abnormal conditions mentioned above.

In adjusting the apparatus, the weighted lever 16 has its weights so adjusted that the differential in pressures on opposite sides of the diaphragm 15 is such that the valve piece 18 will close the thoroughfare 17 when the receiving tank 10 becomes about half filled with water. In this way the vent pipe 11 will be closed by the valve device 13 before water enters the said vent pipe. This adjustment is due to the presence of a sufficient pressure in the supply pipe 3 to cause the water in the pipe 9 and tank 10 to give a head above the water level in the'boiler, such as would maintain the tank 10 about half filled with water. This would be a greater head than the normal head required; and any higher pressure in the boiler, which would cause a head of water being sustained in the pipes 9 and 6 and tank 10, as would produce a discharge of water through the vent pipe 11 if not otherwise prevented, could not produce such discharge because the valve device 13 would hold the vent pipe closed and build up an air pressure in the return pipe 6 and tank 10 which would prevent the rise of water into the pipe 11. While this should prevent rise of the water above the tank in normal operation, it is evident that, if temporarily, any water was forced into the vent'pipe 11, the automatic valve 13 would prevent its escape. As soon as the pressure in the boiler is reduced to a normal condition, the water in the pipe 9 and tank 10 will be lowered automatically by discharge into the boiler and the valve device 13 will instantly respond to open the vent ipe 11. It is evident that, if desired. the c eck valve 12 may be omitted, though in practice I prefer that it shall-be employed for reasons to be described. 1

intense of a lower pressure than the steam pressure in the supply pipes 3. Any vapor in the returns is trifling in character when the valves 7 are properly constructed, and the normal pressure of said vapor is nominally that of the atmosphere, because the valve device 13 in the normal operation of the apparatus is open and the check valve 12 oflers no resistance to discharge into the atmosphere.

While in the normal operation of the system, where the static head of water in the return pipe 9 exactly balances the steam pressure in the supply pipe 3, it is evident that the valve 13 may be normally open to permit escape of any air which may find its way into the tank and the vent pipe 11, and which is brought down with the water of condensation from the radiators. Steam is not permitted to pass from the radiators into the return pipes 6 and thence into the tank 10, because of the presence of the automatic devices or traps 7 which permit the free passage of water and air but restrict the passage of steam. As under these conditions we have a diiierential corresponding to atmospheric pressure on the return side and the initial pressure of the steam on the supply side, there will be a constant'flow of steam through the modulation valves 5 according to the requirements by the mere adjustment of the valves. In view of the fact that when starting up the system with cold radiators or when any radiator is suddenly put into operation and a vacuum is produced therein, it is evident that this is only a temporary condition and one which would naturally tend to draw air from the outside into the system, and the check valve 12 automatically acts to prevent the inflow of air under such conditions. This condition of vacuum, however, does not impair the operation of the apparatus in the slightest, because the vacuum wherever it may exist is upon the return side of the moduiation valves 5, and consequently the system will operate as a perfect heating system in which the water will gravitate back to the boiler and the air which may be temporarily retained to a greater or less extent in the ra diator, will ultimately be driven into the return pipe under the differential between the pressures in the supply pipe and the return pipe. Conditions of vacuum could only continue where the condensing capacity of the radiators would be greater than the supply of steam delivered to them, and while this is an abnormal condition for the operation of a system of this character, it is pointed out, however, that the system, being a closed and tight one which prevents the inflow of air from the outside, will operate during the presence of the vacuum in an automatic manner with great eiiiciency during the continuance of the said vacuum. The operation of the apparatus under a pressure greater than that corresponding to the predetermined static head, such as might occur by providing too great a boiler pressure from any cause unintentionally or otherwise, will cause the circulation of the steam under the same difierential, that is, equal to the predetermined static head due to the lower steam pressure, after the disturbance caused in the system by the raising of the steam pressure has had an opportunity to readjust itself, and this may be explained as follows: Assuming that instead of 1% pounds of steam pressure, there was a 5 pound pressure, which with atmospheric pressure on the return side would make a difierential of 5 pounds, which would sup port a static head of approximately ten feet of water, and consequently the'water would accumulate in thetank 10 and return pipe 6. As the increase in ,difierential would cause the Valve 13 to automatically close the vent pipe 11, no Water would be permitted to escape. In a short time, the accumulations of air in the return pipe driven into it under the steam pressure admitted to the radiators, will build up a return pressure which will equal the excess of the differential over the predetermined amount, and by reason of this, the water in the return pipe .9 will flow into the boiler and the water lowered in the return pipe 6 and receiver tank 10 until the predetermined static head is once more established. This predetermined static head is maintained, because we now have only the 12 pounds as a diiierential although we have 5 pounds steam pressure and 3;} pounds back pressure in the return. This cotdition of the system is then exactly What it was originally when we had 15; pounds steam pressure and atmospheric pressure in the returns. As the governor valve 13 is adjusted to automatically maintain a differential of 1% pounds between the steam supply and the returns, it is evident that it will operate with 5 pounds pressure in the supply to maintain the differential of 1% pounds just the same as it would operate with the steam pressure of 1% pounds. In fact, it will operate the same with any variation in the steam pressure, once the system has rebalanced itself, and at no time will it permit any water to, pass, because no water would tend to pass except when there was a greater ,difl'erential than 1% pounds, and if the regulator was set for that differential, it would not open the valve for any differential above that amount. It is seen therefore, that my improved system is self-regulating and automatic and maintains the cir- .culation of the steam under a definite differential, irrespective of the steam pressure in the boiler; and this enables the system to be operated on the modulation principle in a perfectly controllable manner, for if the difi'erential remains constant during normal operation of the system, the adjustment of the valve will control the amount of heat which is to be given up by the radiators. It is therefore apparent that this system is responsive for variations in the steam pressure without derangement of the system and will maintain its operation at a predetermined differential irrespective of variations in the steam supply pressure and moreover, by the use of the automatic valve 13 in the ventpipe, a constant operative static head may be employed to insure return of the water to the boiler by gravity for various steam pressures corresponding to said static head and above the pressure of the static head, this being a feature which is not found in any other system, as far as I am aware.

I have shown a form of automatic regulator or Valve'device 13 which is suitable for the purposes of my invention, but I do not restrict myself to any particular form of such a device, as any construction of what is commonly known as a reducing valve (similar in general construction to the device 13), may be used for the purposes of my improvements; and likewise, while I have shown a typical form of low pressure heating apparatus, I do not restrict myself to the details thereof, as these may be varied without departing from the spirit of the invention.

In this application, no claim is made to the method of steam heating herein described, as the same is claimed in the separate divisional application filed May 28, 1913, Serial Number 770,293.

Having now described my invention, what I claim as new and desire to secure by Letters Patent, is: I

1. In a steam heating apparatus, the com-' bination of a steam boiler, radiators, a supply pipe leading from the boiler to the radiators, a return pipe from the radiators to the boiler for returning water. of condensation thereto under a normal static head, automatic devices between the radiautomatic valve device to temporarily close the normally open vent pipe operated by means of pressure existing in the steam supply pipe above the normal allowable pres sure therein and arranged to open said vent pipe when the pressure in the return pipe plus the normal allowable pressure in t e boiler equals the abnormal boiler pressure, said valve device consisting of a valve piece to control the thoroughfare in the vent pipe, a diaphragm to operate the valve piece, a

chamber closed on one side by the diaphragm and in communication with the return side of the system, a chamber closed on the other side by the diaphragm and in communication with the supply side of the system, and mechanical adjusting devices for adjusting the action of the diaphragm and valve piece independently of the pressures on opposite sides thereof.

'2. In a steam heating apparatus, the combination of a steam boiler, radiators, a supply pipe leading from the boiler to the radiators, a return pipe from the radiators and connecting with the boiler below the water line for returning the water of condensation thereto, means adjacent to the boiler to prevent back flow from the 'boiler into the return pipe, automatic devices between the radiators and return pipe for permitting the passage of water and air but restricting the passage of steam, a vent pipe in communication with the return pipe and discharging into the atmosphere,- automatic means for closing and opening the vent pi'pe arranged to be closed by the steam pressure from the boiler whenever the said boiler pressure exceeds a predetermined normal pressure capable of supporting a definite static head in the return pipe and arranged to be 0 ened by the pressure in the return pipe .w enever the said pressure in the closed return pipe added to the pressure of the normal static head exceeds the boiler pressure, and mechanical means for adjusting said automatic means so that it will close the vent pipe by the steam pressure when a definite static head has been produced in the return pipe.

3. In a gravity system of steam heating, a steam boiler, radiators, a sup ly pipe and a return pipe connecting said boller and radiators and forming therewith a circulating system, combined with return valves at the outlets of the radiators for permitting the passage of air and water and restricting the passage of steam, a vent from the return pipe at a point above the normal water level therein and open to the atmosphere, and an automatic valve device in said vent and wholly outside of the return pipe and passage to the boiler and out of contact with and operating independent of the water in the system having a steam actuated part operated by the pressure in the supply pipe and an adjustable gravity actuated means to actuate the valve device to control the degree of pressure at which the openlng and closing of the valve takes place, for automatically closing the vent and maintaining it closed when abnormal pressures exist in the boiler.

l. In a gravity system of steam heating, a boiler, supply and return pipes extending from the boiler, radiators connected between the supply and return pipes, automatic devices between the radiators and the return pipes for permitting the passage of air and water from the radiator but preventing the passage of steam, a vent pipe from the return pipe normally open to the atmosphere, and an automatic valve device controlled by the differential in pressures in the supply and return sides of the system to close for all steam pressures above a predetermined normal pressure and independently or" the water level in the return pipe for automatically closing the vent and maintaining it closed whenever and so long as a predetermined relative pressure in the supply side of the system is exceeded.

5. In a steam heating apparatus, the combination of a steam boiler, radiators, a supply pipe leading from the boiler to the radiators, a return pipe from the radiators to the boiler for returning water of condensation thereto under a normal static head, automatic devices between the radiators and return pipe for permitting the passage of water and air and restricting the passage of steam, a receiving tank for receiving the water of condensation and air from the return pipe arranged at an elevation above the water level of the boiler in communication with the return pipe and through which the water passes on its way to the boiler, a

check valve to prevent water flowing from the boiler into the receiving tank, a vent pipe in communication with the receiving tank and discharging into the atmosphere, and an automatic valve device outside of and independent of the tank and directly operated by the pressure conditions in the steam supply pipe and independent of the water in the system to temporarily close the vent pipe and build up the air pressure in the tan'k whenever and for so long as the differentials in pressure existing in the steam supply pipe and the return pipe become and remain abnormal by an excessive steam supply pressure.

6. In a steamheating apparatus, the combination of a steam boiler, a radiator, a supply pipe and a return pipe connecting said boiler and radiator and forming therewith a circulating system, the return portion of said system having a normally open outlet above the normal water level therein, means for preventing the flow of steam from the radiator to the return pipe whereby a given differential of pressure may be maintained between the radiator and the return pipe, and means for maintaining said differential of pressure, said means comprising a pressure actuated valve device for controlling said normally open out-let arranged to be operated by the variation of pressures when a pre-determined pressure in the supply side of the system is exceeded.

7. In a steam heating apparatus, the combination of a steam boiler, a radiator, a supply pipe and a return pipe connecting said boiler and radiator and forming therewith a circulating system, the return portion of said system having an outlet, a steam actuated valve device in communication with the supply side of the system for controlling said outlet, said outlet and valve device being in communication with the system above the normal water level therein, and the said valve device being adapted to close said outlet when a predetermined pressure in the supply side of the system is exceeded.

8. In a steam heating apparatus, the combination of a steam boiler, a radiator, a supply pipe and a return pipe connecting said boiler and radiator and forming therewith a circulating system, the return portion of said system having an outlet arranged above the normal water level therein and normally open to the atmosphere, and a pressure actuated valve device for controlling said outlet, said pressure actuated valve device being in. communication with the system above the normal water level therein, arranged to be acted upon differentially by the pressures in the supply and return portions of the system, and adapted to close said normally open outlet when a predetermined pressure in the supply side of the system is exceeded.

In testimony of which invention, I hereunto set my hand.

JAMES L- FIT-TS.

Witnesses:

F. JOSEPH MILLER,

PHILIP Y. QUINN.

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